Fruit IPM Reports

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Fruit IPM Report

All degree day totals, and model outputs are based on data collected from a NEWA-connected weather station in an orchard in Concord, NH. Be sure to enter your specific biofix dates for your farm for the best results and accuracy.

Today we are at a total of 2827 DD 43F BE and 1960 DD 50F BE since January 1, 2024.

Novel Detection of Blueberry Gall Midge in NH Blueberries

Researchers from the UNH Insect Collection have detected two previously unreported species of blueberry gall midge in the state's blueberry crops. To learn about what they have found please visit our blog post at: Novel Detection of Blueberry Gall Midge in New Hampshire Blueberry Crops | Extension (unh.edu)

Apples

Recent rains are welcomed and just in time to help with fruit sizing. The rains may also help to suppress BMSB and mite populations.

Apple maggot fly – Are you getting trap captures? We are still getting almost zero captures in some locations where we monitor. This insect can have populations that vary significantly from one site to the next, so monitoring at your farm is the best way to know what is happening relative to fly emergence for your location. Remember to think about multiple insects when considering controls. Pre-harvest intervals are also a factor at this time, so consider that as well when determining if and when to apply insecticides.

Codling moth numbers, for example, remain at levels where treatment may be needed in some orchards, depending on timing of past applications. Pay attention to rainfall totals and the material used and keep up with reapplications as needed.

Figure 1: Example of codling moth trap captures at one location in Merrimack County over the 2024 season.

BMSB – Who’s trapping for BMSB in their orchards? Trap options include clear sticky cards or the pyramidal Tedders traps which mimic tree trunks. While firm action thresholds for New England are not established, considerations for when action is needed can be found here.

Stop-drop materials – For many, we are within the window of application to apply one or more of the materials available to help retain fruit on tree for longer while delaying the ripening process. An excellent summary about the most commonly used materials and when to apply this, along with combinations and their potential benefits can be found here.

Sooty blotch/fly speck and summer diseases

These hot and humid conditions are ideal for the development of summer diseases. Remember to keep track of fungicide application dates and consider rainfall events and totals to ensure adequate coverage and control are maintained. NEWA has a model for SBFS which takes into consideration your last fungicide application and rainfall events to estimate risk of infection. Be sure to select a weather station location closest to you for best accuracy. View the model here: https://newa.cornell.edu/sooty-blotch-flyspeck

Peaches

Brown rot – We are right in the middle of the peach harvest season in many locations in NH. Brown rot is the primary disease concern in the three weeks leading up to harvest across varieties. There are many fungicides with good efficacy, most of which have a 0 to 1 day PHI. Maintain coverage and consider rain events. We have observed plenty of brown rot in untreated or low-spray orchards, so be aware and stay on top of management as harvest approaches.

Oriental Fruit Moth

Trap captures are relatively low in most locations where we monitor at this point in the season. We have seen trap captures spike around the second to third week in May, again about a month later, and now with variability depending on location. Continue to monitor populations, taking into account other pests and controls applied to weight risks of this pest to your crops.

Figure 2: OFM trap captures over the 2024 season at one representative location in Merrimack County, NH.

Fruit in general

Spotted wing drosophila (SWD) numbers are down a little from last week. We trap for SWD in Goffstown, Concord, Litchfield and Hollis, NH. Trap captures by crop can be found in Table 3 below. If you have susceptible ripening fruit, it is recommended to monitor and manage for SWD, especially as blueberries, fall raspberries and day-neutral strawberries continue to ripen. The hot and humid weather is ideal for SWD development. More information on monitoring for SWD can be found here.

Table 3. Male SWD trap captures, 8/5/24-8/9/24.

Upcoming events:

The last of the tree fruit twilight meetings will take place next Wednesday, August 21^st at Apple Hill Farm in Concord, NH. Remember, you do need to register by today (8/15) if you plan to stay for the cookout. If this is a last-minute registration, please email Samanthabf08@gmail.com. The food sounds amazing, so I highly recommend sticking around. Details about the event can be found here: https://extension.unh.edu/event/2024/08/tree-fruit-twilight-meeting-apple-hill-farm

More about the meeting and cookout from NHFGA:

 Join us on the 21st for a 1-hour Twi-light meeting where we look at a trial block of Premier Honeycrisp on G935 where UNH Ext. will explain the different applications of Mycorrhizal fungi and the resulting effect on tree growth. Then we look at a trial planting of peaches, and nectarines. Three trees each of over 30 different varieties. We will have a peach tasting for you at the farm stand with all of the varieties that we can either store till that date or are ready near the 21st.

After last years’ devastating crop loss, we felt that it was time to just get together and socialize, enjoy a home cooked meal and some New Hampshire ciders. The meal will consist of Robertson’s famous barbeque Chicken, (1/2 chicken per serving) many of us know Jamie Robertson from Contoocook Creamery. Sweet Corn, Coleslaw, Cucumbers, Tomatoes, and Beverages of all sorts. We encourage you to BYOBC (bring your own best cider) for sampling. Dessert will be Peach Pie and Peach crisp with ice cream. Come one, come all, bring your employees. The Apple Hill Jamaican farmers will be helping Jaimie Robertson with a Jamaican jerk seasoned version of the chicken. The cost is $10 per head.

We do need you to pre-register so we can get the right number of chickens. We must have that number by the 15th of August.

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Fruit IPM Report

All degree day totals, and model outputs are based on data collected from a NEWA-connected weather station in an orchard in Concord, NH. Be sure to enter your specific biofix dates for your farm for the best results and accuracy.

Today we are at a total of 2454 DD 43F BE and 1685 DD 50F BE since January 1, 2024.

Dry conditions persist in southern NH, though some locations have received rainfall during the first half of the week. Hopefully, you are in one of those locations. As of August 1, 2024, all counties in NH except Coos have at least some portions categorized as abnormally dry, with portions of Hillsborough, Merrimack, Rockingham, and Strafford having portions categorized as reaching D1 drought status.

Hot temperatures have been a concern for apple growers, and the application of sunscreen products seems to be on the rise. Read more about sunburn and options for management at: University of Maryland and Washington State University.

Apples

Sooty blotch/fly speck and summer diseases

These hot and humid conditions are ideal for the development of summer diseases. Remember to keep track of fungicide application dates and consider rainfall events and totals to ensure adequate coverage and control are maintained. NEWA has a model for SBFS which takes into consideration your last fungicide application and rainfall events to estimate risk of infection. Be sure to select a weather station location closest to you for best accuracy. View the model here:

https://newa.cornell.edu/sooty-blotch-flyspeck

Apple maggot fly – So far this week we have captured zero AMF flies in our unbaited red sticky traps. Most locations which we monitor have yet to reach the threshold of an average of 2 flies per trap. In some locations, we have yet to catch a single fly. Perhaps the spotty rain showers will change that this week in some locations, so continue to monitor traps frequently to know when emergence begins. UNH Extension monitors for AMF weekly in five orchards located in Merrimack and Belknap Counties.

Codling moth – Flight of the second generation continues in the Concord area as of August 1^st, 2024. If significant fruit damage from the first generation is present, control of the second generation becomes even more important. CM larval entry occurs at the stem or calyx end of fruit. Feeding around the seeds is a key identifier of CM. Monitor your traps to mark the date of the 2^nd flight (biofix) for your location, and time applications for 250 DD past this point.

For example, on 7/19 in Concord we had accumulated 1215 DD 50F since our initial biofix date (5/18) of the first-generation moth captures. Optimal timing for insecticides to control hatching larvae should be 250 DD 50F BE from our 7/19 DD accumulations. This would put us at about 1460 DD for optimal timing in this location. Today in Concord we are predicted to reach 1491 DD, this putting us in the prime window of opportunity to control CM hatching larvae.

Spinosads and diamides are some of the best options for management. Diamides have some of the greatest persistence on the trees after application are high in these materials, providing longer-term protection through rain events. Please remember to rotate chemical classes from first generation to second generation to limit insecticide resistance.

Peter Jentsch, former director of the Huson Valley Lab in Highland, NY, showed that pyrethroids lose efficacy when temperatures get warm (above 70F.) Larvae can detoxify these insecticides in warm conditions, so other insecticide classes are better for control given the current weather conditions.

Remember to rotate IRAC classes between the first and second generations of this insect for resistance management. For example, if you used a group 28 insecticide such as Altacor, Exirel or Verdepryn to manage the first generation, switch to something like a group 4A such as Assail. The main point is that we rotate chemical classes between generations.

Codling moth adults on sticky trap with pheromone lure. Photo credit: Justin Hogg, UNHCE Scout

OFM and OBLR – Trap captures for both of these moths remain very low as of this week on the farms we monitor. Continue to monitor traps to see if adult captures increase in the coming weeks.

Stink bugs – BMSB egg masses and nymphs are starting to be reported in higher numbers. Feeding damage may not be apparent until one to two weeks after feeding. Sticky trap threshold is suggested at 1-3 adults/week, while with Teders traps, threshold is suggested at 10 adults/trap/week.

Mites – Irrigation and rain events tend to help suppress mite populations. European spider mites create webbing that helps them persist. July threshold is 5 mites per leaf for European red mite, and 7.5 mites/leaf in August. Weed control may increase populations on apples trees as they move from weeds up into the canopy after herbicide populations. In in-depth blog about mites can be found here: https://blogs.cornell.edu/jentsch/2015/07/18/mite-management-reduced-risk-pest-management-in-apple/

Peaches

Stink bugs - BMSB egg masses and nymphs are starting to be reported in higher numbers. Feeding damage may not be apparent until one to two weeks after feeding. Sticky trap threshold is suggested at 1-3 adults/week, while with Teders traps, threshold is suggested at 10 adults/trap/week.

For a great listen, check out the podcast from former IPM State Specialist, Anna Wallingford all about Integrated Control of BMSB.

A report of green stink bug nymphs in peaches was submitted by a grower in Rockingham County this week after noticing oozing wounds on the sides of ripening peaches. Nymphs are the easiest stage of this pest to control. This is a situation that needs to be closely monitored, as chemical control options with short pre-harvest intervals are few, and timing must be carefully considered.

Photo: Green stink bug nymph on ripe peach

Brown rot – The earliest varieties of peaches in our trial at Apple Hill Farm in Concord, NH, were harvested on 7/23. For later varieties still within the window of three weeks from harvest, we are still in an important time for the control of this fungus on fruit. Be sure to consider pre-harvest intervals as you select fungicides. There are many fungicide options rated as good or excellent for control at this stage of the season, which can be viewed in the New England Tree Fruit Management Guide here: https://netreefruit.org/stone-fruit/peaches-nectarines/spray-table/6-summer

Japanese beetles are active now. Be sure to monitor peaches, nectarines and other susceptible crops and control as needed. Again, be mindful of PHI depending on material choice.

Blueberries

Growers are transitioning into mid-season varieties such as Duke, Patriot, Blueray, Bluecrop, Reka and Toro. More information about variety selection for an extended harvest can be found here: BlueberryCultivars (unh.edu)

Spotted wing drosophila (SWD) numbers are down from last week. We trap in Goffstown, Concord, Litchfield and Hollis, NH. Trap captures by crop can be found in Table 3 below. If you have susceptible ripening fruit, I recommend monitoring and managing for SWD, especially as blueberries continue to ripen. The hot and humid weather is ideal for SWD development. More information on monitoring for SWD can be found here.

Male SWD trap captures, 7/22/24-7/28/24.

Anthracnose

Anthracnose (Colletotrichum acutatum) is beginning to show itself in some locations. As explained in the New England Small Fruit Management Guide, This fungus primarily damages fruit, but may also infect twigs and spurs. Infected fruit often exhibit a soft, sunken area near the calyx-end of the fruit. Salmon-colored spores spread to “good” fruit during and after harvest, causing significant post-harvest losses. The disease is especially prevalent during hot muggy weather and frequently occurs post-harvest. Leave a couple dozen fruits out on the counter for 2-3 days to see if you get any sporulation. This will give you a good indication as to the disease pressure in your patch from this particular fungus.

Anthracnose overwinters in dead or diseased twigs, fruit spurs, and cankers. Spores are released in spring and are spread by rain and wind. Blossoms, mature fruit, and succulent tissue are infected, and spores may be spread from these infections. Infected blossom clusters turn brown or black. Infected fruit show salmon-colored spore masses at the blossom end. Stem cankers are rare, but are about 1/8” in diameter, with raised purple margins when they are present. Young, girdled stems die back, resulting in a brown withering of leaves. Bluecrop, Bluetta, Chanticleer and Spartan are particularly susceptible to anthracnose. Elliot and Weymouth appear to have good resistance.

Management: Anthracnose is controlled primarily with fungicide applications, though pruning for optimal air circulation and clean harvesting are beneficial. Old canes and small twiggy wood should be cleared out in order to increase air circulation around the fruit clusters. See pest management schedule for recommended materials and timing.

Upcoming Events:

August 21 – Tree Fruit Twilight Meeting at Apple Hill Orchard in Concord

Tree Fruit Twilight Meeting at Apple Hill Farm | Extension (unh.edu)

At this meeting we will have one hour of education to include an update on the progress of the mycorrhizal fungi trial, and a visit to the peach/nectarine variety trial. We will do some tasting of the varieties that are ripe, and will be joined by Dr. Renae Moran, UMaine Tree Fruit Specialist, for an update about the findings of the cold hardiness portion of this trial. After the educational program, we will have a cookout/social to reconnect with friends and celebrate the season. More details will be forthcoming from the NH Fruit Growers Association soon regarding registration for the cookout.

The Climate Adapted Farm: Making the effects of extreme weather less severe

Join NH Vegetable and Berry Growers Association (NHVGBA) & UNH Extension for this climate-resilience focused series. Attend one or more events to learn how your farm can adapt to better withstand the challenges of climate change, and how together we are working towards farmer-driven actionable solutions. This is a four-part series, join us for one or the full slate! 

 August 20, 2024 | 5:30 - 7:30pm, Resilience Against Extreme Weather at Wilson Farm, Litchfield, NH. What's your plan B when disaster strikes? Explore concrete actions to prepare your farm for floods, droughts, or extreme heat and get introduced to emergency management planning. 

Organic No-till Vegetable Production and Protected Agriculture

August 21, 2024 | 5:30 - 7:30pm at Uphill Farm, Whitefield, NH

This evening discussion will be on organic no-till vegetable production. We will discuss vegetable production in northern New Hampshire, establishing and managing no-till systems, and explore pest exclusion systems for leek moth and swede midge. Uphill Farm will also highlight its efforts to transition towards precision irrigation with assistance from the Coös County Conservation District Climate Resiliency Grant.

Please sign up for our text service! Text UNHIPM to 866-645-7010 to subscribe.

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Fruit IPM Update 

All degree day totals, and model outputs are based on data collected from a NEWA-connected weather station in an orchard in Concord, NH. Be sure to enter your specific biofix dates for your farm for the best results and accuracy.

Today we are at a total of 1514 DD 43F BE and 956 DD 50F BE since January 1, 2024.

Notice: The EPA is soliciting comments regarding Captan fungicide until July 31^st. These proposed rule changes would impact tree fruit and grape producers. For details on the proposed changes and how to submit your comments, visit:

https://extension.psu.edu/epa-soliciting-comments-for-captan-fungicide-submit-comments-by-july-31-2024

Apples

Fireblight – Growers continue to report blossom and shoot strike infections. We should be nearing terminal bud set which should bring with it a major decline in any new shoot strikes. Prune out strikes 18-24” below visible symptoms into older wood where possible. If removing an entire branch, leave a small stub as a place for the bacteria to dry out and die before reaching the main leader.

Prohexadione calcium (PhCa) is still an option until terminal bud set at 6-12 ounces per 100 gallons with liquid copper. If the decision is made to apply this mix to a block of trees, wait 5 days for the PhCa to work before pruning out strikes. Some researchers suggest to only cut out shoots with a wet oozing appearance and leave those that appear dry after the treatment above.

Apple scab – Secondary scab is present in some orchards. Recent hot temperatures and fungicide applications seem to have slowed down active infections. In orchards with active secondary infections, continue to maintain coverage, scout to monitor status of infections, and remain mindful of temperatures and rainfall accumulations since your last application of fungicides.

Regional pathologists are recommending materials such as potassium bicarbonate, or the combination 7 + 11 FRAC group materials such as Merivon and Luna Sensation. These materials should also help to control powdery mildew infections.

A recent blog post from Dr. Kari Peter at PSU provides guidance on both scab and fireblight management, along with considerations for scab management programs in future years to minimize infections:

https://extension.psu.edu/2024-disease-update-managing-fire-blight-and-apple-scab-infections

Sooty blotch/Flyspeck – Fruit is susceptible to infections now. Consider your market, last fungicide application timing, leaf wetness hours and rain events when contemplating the need for control. The NEWA SBFS model currently shows a low risk of infection this week.

Bitter rot

With the arrival of summer weather comes the increased risk of bitter rot. UMass has an excellent fact sheet explaining the key management points to keep in mind here:

https://ag.umass.edu/fruit/fact-sheets/apple-ipm-bitter-rot

Group 7, 11, combinations of the two, along with multi-site materials are rated as having the highest efficacy.

Powdery mildew - Continues to linger in many locations. Prune out infected shoots where possible to reduce inoculum. As mentioned above, the group 7+11 combination products will also provide some control.

Apple maggot fly – Traps should be up in anticipation of flies. We have yet to capture our first fly as of 7/2/24.

Codling moth – Trap captures of male moths have declined significantly over the past week in most locations, likely marking the tail end of the first-generation flight. Today in Concord we are predicted to reach 761 DD 50F BE since biofix (5/18/24). Peak egg hatch of the first-generation CM larvae is predicted at 500-600 DD from biofix, so most eggs from the first flight should have hatched by now in most locations. First insecticide applications for the second generation should be made at about 1,400 DD to 1,600 DD, using the same biofix as previous spray timing.

Obliquebanded leaf roller – So far, we have accumulated 538 DD 43F BE since our first trap catch. Adults are still flying and laying eggs. Peak flight usually occurs within two weeks after the first adult is captured. Eggs begin to hatch at approximately 350 DD base 43F after first trap catch. It is still too early to sample for larvae in orchards that are being monitored to determine if summer control sprays are necessary because most egg masses (about 75%) still have not hatched. Residual activity from an initial protective spray will control early hatching larvae at this time.

Jaime Pinero of UMass Extension reminds us of the following consideration when evaluating the magnitude of OBLR populations:

• While it is recommended to spray insecticides that target the hatching larvae at 360 DD base 43 after BIOFIX, we also need to consider the magnitude of the OBLR captures. 
• OBLR undergoes two generations annually, with larvae overwintering as small larvae in trees. They become active upon the trees breaking dormancy, completing their development about two weeks after the apple blossom period.
• Because high OBLR trap captures often don’t translate to high levels of injury growers are advised to scout for summer generation larvae by examining 10 fruit clusters and 10 terminals on five trees per orchard each week. Using this method, an insecticide application is warranted if three larvae per tree are found. 
• The second generation's adult flight occurs in August, and larvae hatch in August and September. These young larvae create hibernation sites on twigs or bark to survive the winter. 

Potato leaf hopper – Hopper burn is evident in parts of New England and NY. Management is most important for young trees as they are growing to fill their space. Monitor over the next couple of weeks to see if they show up here in numbers.

Wooly apple aphid – WAA feed on shoots and excrete sugary material which serves to encourage sooty mold. Scout for aerial colonies in leaf axles. Most have been found in branch crotches and pruning stubs to this point in the season. Movento is one of the most effective materials if control is deemed necessary.

Apple maggot fly – We have yet to catch our first fly on unbaited red sticky traps in Merrimack County. We will continue to monitor and report once captures have occurred. Suggested treatment threshold is an average of 2 flies per trap on unbaited traps, and 5 flies per trap when baited. As we anticipate adult fly emergence soon, the article from Michigan State University may be helpful as you consider insecticide choices. Some of the materials listed are rated as highly effective on codling moth as well. A consideration when timing for control of both insect aligns.

https://www.canr.msu.edu/news/managing-apple-maggots-with-insecticides

Peaches

Brown rot – The earliest varieties of peaches in our trial at Apple Hill Farm in Concord, NH tend to ripen around July 26^th. That would make this Friday about three weeks from harvest, and the beginning of an important time for the control of this fungus on fruit. There are many fungicide options rated as good or excellent for control a this stage of the season, which can be viewed in the New England Tree Fruit Management Guide here: https://netreefruit.org/stone-fruit/peaches-nectarines/spray-table/6-summer

Japanese beetles are active now. Be sure to monitor peaches, nectarines and other susceptible crops and control as needed.

Blueberries

Early varieties are ripening with the earliest just starting to be harvested in southern NH locations.

Fruits infected with mummyberry are evident throughout the southern half of NH this year. Conditions were favorable for the fungus to cause infections during budbreak through bloom. Sanitation including removal of infected fruit during harvest to the extent possible will help minimize inoculum for next year.

Blueberry maggot - Early varieties are ripening, so knowing if this pest is present will become increasingly important. Unlike SWD, which tends to show up in most locations with berries in NH, blueberry maggot tends to be more site specific, therefore monitoring for presence has great value in IPM programs. Also worth noting is the fact that if you do have populations of this pest, most of the materials rated as highly effective for controlling SWD will also control this pest.

SWD – Populations are increasing quickly now in the southern half of NH. Growers should have traps up to monitor SWD first appearance and consider best timing of controls for all ripening berries.

Cornell provides a timely reminder of best management practices for SWD, along with their updated SWD Insecticide Quick Guide below:

Quick Guide: https://bpb-us-e1.wpmucdn.com/blogs.cornell.edu/dist/f/7312/files/2024/05/Quick-Guide-SWD.pdf

Below are a few reminders of management tactics that should be used to successfully manage SWD this season:

Sanitation – Harvest fruit frequently to prevent populations from building up. If possible, do not leave berries on the ground. Remove infested fruit and freeze, seal in bag and place in the sun or dispose off-site.

Canopy management – Excellent pruning and weed management reduce humidity, creating an environment less conducive to SWD.

Monitoring – Begin to spray as soon as fruits begin to ripen, once SWD has been trapped in your orchard/region.

Rotate active ingredients (IRAC groups) through to harvest for resistance management. Resistance has been documented in other states, rotating is essential for preventing this in our region!

Avoid the temptation to stretch spray intervals! 7-day interval should be the maximum.

Plan out the order of insecticides you will use wisely, so that you save products with a lower PHI for use close to harvest.

Focus on complete coverage, especially in the middle of the canopy where high humidity creates an ideal SWD habitat and be sure to reach to the top of the tree.

If it rains, reapply (according to label instructions).

When choosing insecticides for European Cherry Fruit Fly and native Tephritid fruit fly control, prioritize those that have activity against SWD (more information about ECFF to come in an upcoming Fruit Notes issue).

Exclusion – Polyethylene netting (80 gram or 1.0 x 0.6mm) requires a high upfront installation cost and must be very thoroughly maintained to provide no possible entry to the flies, but if done well can be an extremely effective method of preventing infestation. Exclusion netting must be installed before SWD arrival and must be well maintained.

Strawberries

Harvest of June-bearing is nearly complete, aside from the latest varieties like Malwina. This means the time for renovation is here. For an excellent guide on the process and considerations, visit the following MSU article: https://www.canr.msu.edu/news/renovation-in-perennial-strawberry-fields

Raspberries

The crop looks good overall. Early varieties are ripening in southern locations. The beginning of harvest for early varieties is anticipated next week in the Concord area. SWD has a preference for raspberries, so have you traps up and be prepared to protect ripening berries.

Pesticide Safety Education

Lastly, my colleague Rachel Maccini oversees the Pesticide Safety Education Program in NH. She asked that the following be included in this update for your information.

What license do I need?

In New Hampshire, anyone applying pesticides for producing an agricultural commodity must be licensed as a private applicator. According to state regulations, a private applicator is an individual who uses or oversees the use of pesticides, whether classified as general use or state restricted use, for agricultural production on property they own or rent, or on another's property without monetary compensation, except for personal service exchanges between agricultural producers. An agricultural commodity includes plants, animals, or animal products produced primarily for sale, consumption, propagation, or other use by humans or animals.

Private applicator permits are specific to the commodity produced and there are ten categories: Christmas Trees, Nursery, Greenhouse, Small Fruit, Tree Fruit, Beekeeper, Poultry, Dairy, Vegetable, and Sod, each associated with particular pests and sites. There are two types of pesticide permits: General Use and Restricted Use. A Restricted Use Permit is necessary for individuals using restricted pesticides or applying pesticides in a restricted manner. To obtain a Restricted Use Permit, an applicant must submit an application, exam application, and fees, then schedule a written exam with the Division of Pesticide Control within 30 days of application receipt. Alternatively, the exam can be taken at a county extension office with prior arrangements.

If you have questions about licensing please reach out to Beth Cladwell, Certification Coordinator (licensing), email: beth.k.caldwell@agr.nh.gov or (603) 271-3694.

How do I check to see if a pesticide product is registered in NH?

Pesticides sold within New Hampshire are registered with the Division of Pesticide Control (NH Dept of AGR, Markets & Food). You can check their data base by visiting https://www.agriculture.nh.gov/publications-forms/documents/registered-pesticide-products.pdf

Once you are here you can do control F and type in your EPA Reg. #, if the product was or is registered it will highlight within the document. If the product is not registered in NH, the EPA Reg. # field will highlight red indicating there is no record of that particular product. The product registration information is updated annually around March. If you are interested in a particular product, but do not see it on the list you can reach out to the Division of Pesticide Control (NH Dept of AGR, Markets & Food) for assistance (603) 271-3550.

Where can I obtain a copy of a pesticide label if mine has been damaged or is missing?

If you need to obtain a copy of a pesticide label due to damage or loss of the original, there are several resources available to you. The manufacturer's website is a good starting point, as they often provide downloadable labels for their products. Additionally, the National Pesticide Information Center (NPIC) offers a searchable database where you can find labels for various pesticides.

http://npic.orst.edu/ingred/proddata.html

Another useful resource is the Pesticide Product Label System (PPLS) managed by the U.S. Environmental Protection Agency (EPA), which provides access to current and historical labels.

https://ordspub.epa.gov/ords/pesticides/f?p=PPLS:1

The CDMS (Crop Data Management System) is another great site. https://www.cdms.net/LabelsSDS/home

If these options do not yield results, contacting the retailer or distributor where you purchased the pesticide may provide a quick solution.

I have some old pesticides that I no longer need. How and where can I dispose of them? What do I do?

Disposing of old pesticides requires careful attention to ensure environmental safety and compliance with local regulations. First, check the labels on the pesticide containers for any specific disposal instructions provided by the manufacturer. If these instructions are not available or unclear, your best course of action is to contact your local waste management facility or the environmental health department. Many communities have designated household hazardous waste collection programs that accept pesticides and other hazardous materials. These programs often provide specific drop-off locations or scheduled collection events. It’s crucial not to dispose of pesticides in regular trash, drains, or by pouring them on the ground, as this can cause significant environmental harm.

Household Hazardous Waste Days. Information and collection events can be found here: https://www.des.nh.gov/sites/g/files/ehbemt341/files/documents/hhw-collection-contacts.pdf

Active Hazardous Waste Transporters in New Hampshire: The “Yellow Pages” may have listings for vendors or contact the state of New Hampshire’s Hazardous Waste Hotline at (866) HAZWAST (1-866-429-9278) (toll free in-state 8 am to 4 pm) or (603) 271-2942 for further guidance.

The following list of hazardous waste vendors does not constitute endorsement or preference but represents vendors that may manage pesticide waste:

Maine Labpack Inc.

15 Holly Street, Suite 201

Scarborough, ME 04074

Phone # 207-767-1933

Triumvirate Environmental Inc.

200 Inner Belt Rd

Somerville, MA 02143

Phone #617-628-8098

New England Disposal Technologies Inc.

83 Gilmore Dr

Sutton, MA 01590

Phone #508-234-4440

Toll Free 800-698-1865 Email: sales@NEDTinc.com

Agricultural producers are also encouraged to contact the Division of Pesticide Control at 603-271-7788.

Attention Agricultural Producers:

We are pleased to inform you that the Lakes Region Hazardous Product Facility is now able to handle the disposal of agricultural pesticides. This service is available with prior notice and offers a cost-effective solution for managing your hazardous products.

To ensure a smooth and efficient process, please follow these steps:

Prepare a List: Compile a list of the agricultural pesticides you need to dispose of, including details on the condition and size of each product.

Contact Sara Silk: Reach out to Sara Silk at 651-7530. It is important to do this well in advance of your desired pickup date.

Arrange for Pickup: Discuss the specifics with Sara Silk to arrange for the pickup of your agricultural pesticides.

Fees: Be prepared to pay a fee for this service. However, please note that the fee is significantly lower than what is typically charged for commercial waste disposal.

For further assistance and information, you can also contact the Division of Pesticide Control at (603) 271-7788.

Upcoming Events:

August 21 - Tree Fruit Twilight Meeting at Apple Hill Farm | Extension (unh.edu)

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Fruit IPM Report 7/18/23

Hi all!!  

 Welcome back to the NH Fruit Pest hotline, which is produced by staff members from the UNH Cooperative Extension Food and Agriculture team.   Today is July 18^th , 2023.

While these recordings will highlight what you need to be looking for out in the field, I highly encourage you to find the transcripts online, as they will have more details and links about many of the pests, products, and models I’ll be describing in this call. Simply google “UNH Fruit IPM reports” to find them on our webpage. The transcript for this call may not be up until Wednesday afternoon.

In terms of growing degree days in Concord, NH we have accumulated 1823 GDD in BE base 43F and 1105 GDD in BE base 50F.

Weekly pest and disease update:

Diseases:

Mummy berry on Blueberry:

 Is being reported from some blueberry plantings. Details about this disease and management strategies can be found here.

This infects new shoots in the very early spring beginning around budbreak. Those infected shoots can then in turn release spores that infect open flowers, eventually resulting in the symptoms you are seeing in your berries. The fruit you see there will eventually shrivel and look like a little grey or black pumpkin. This lies in wait until next spring for conditions to be just right and releases new spores to continue the cycle. You can read more about the disease here: Microsoft Word - Blueberry IPM - Mummy Berry Final.docx (umass.edu)

This year was certainly a good weather year for this fungus. We had temperatures conducive for extended persistence of apothecia (spore producing structures). As noted in the fact sheet below, as apothecia expand, the number of ascospores released increases. Ascospore discharge depends on temperature, relative humidity, and wind speed. Apothecia can persist for about 3 to 4 weeks under cool conditions — 50° to 59°F  — but are shorter lived as temperatures rise. At 68° to 77ºF (20° to 25°C), they may persist for only 1 to 2 weeks.  We had damage from the freeze, which likely damaged tissues. Did you see many shoot strikes? These would've been visible around the time that flowers were present. The fact sheet below gives detailed information about the disease cycle and includes photos of berries as the life cycle progresses. I know many of you are familiar with this, but there is good information in there and helpful pictures.

https://www.canr.msu.edu/blueberries/uploads/files/E2846%20Mummy%20Berry%20Facts.pdf

A list of fungicides and their efficacy is also included in the fact sheet above.

Mulching with at least 2” of fresh mulch in the fall can also greatly help reduce the number of spores that are able to reach susceptible tissue. This strategy can’t be used year after year due to too much mulch buildup, but if you need to mulch, this fall would be a great time for this reason. Also, picking off as many of those suspicious fruits as possible will only help to reduce potential inoculum for next season.

One last tip…You could collect 10-20 of the mummies and create a “mummy garden”. I know, it sounds funny, but you could place them outside the planting, possibly just nestled in some wood mulch (not fully buried) and use that to track the development of the disease development next year. Once you see the little mushroom cups coming up, it will clue you in as to when you need to treat. Research shows that the fruiting bodies of the fungus (apothecia) need to be at least 1/12” in diameter to produce spores for infection.

Moving onto the apples:

Bitter rot:

Conditions have been good for this disease with lots of rain, and quite a bit of fruit showing some sort of injury (notably, cracking) that might allow entry to the pathogen. Captan does a pretty good job, especially at slightly elevated rates. PennState cites Merivon/Pristine, Flint/Luna Sensation, Aprovia, and Omega, mixed with Captan as being effective.

For more info: Apple and Pear Disease - Bitter Rot (psu.edu) and Bitter Rot | New England Tree Fruit Management Guide (netreefruit.org)

Apple scab:

 Hopefully your orchard is clean of scab for the growing season. While visiting orchards, extension staff have seen some scab infections present on leaves. In those orchards, growers will need to remain diligent and maintain fungicide coverage to minimize new infections. . If new infections are showing up in your orchard, control measures are warranted.

Here is an article addressing control and resistance management strategies for scab:

https://www.canr.msu.edu/news/management_of_apple_scab_in_orchards_with_existing_scab_lesions

An excellent description of the factors to consider for best fungicide selection can be found here: https://netreefruit.org/apples/diseases/apple-scab

Fireblight:

There has been plenty of fireblight popping up on apple orchards around the state from southern New Hampshire all the way up into Carroll County.

Continue to scout orchards for shoot blight, including rootstock sucker infections. Prune and remove infected shoots at least 12-18 inches below the infected margin during cool, dry weather.

Pruning is particularly useful when blossom blight is well controlled and canker blight infections are thus the main source of inoculum for disease spread during the summer. Pruning can help limit disease spread but will be most effective if practiced rigorously during the first few weeks after bloom; pruning will do little to slow disease spread if delayed until a large number of infections are visible.

Routine use of antibiotics to prevent shoot blight spread during the summer is not effective or recommended. However, applications to protect new wounds immediately following a hailstorm can be very beneficial. With a cool and fairly dry bloom period, some growers made in through the prime infection period with just a couple of streptomycin applications. Keep in mind that saving at least one or the four allotted strep sprays in case of hail or damaging wind events is a good insurance strategy.

In a recent report, Kathleen Leahy reminds us of an article from Good Fruit Grower highlighting recent research comparing cutting and sanitization strategies to find the best removal methods for fire blight strikes. It’s definitely worth the read:

Good to Know: Take a bite out of blight - Good Fruit Grower

Another great resource on fireblight management options comes from Dr. Kari Peter, Tree Fruit Pathologist at Penn State University. Her presentation from our UNH Fireblight Webinar can be accessed here.

Sooty Blotch and Flyspeck:

Now is the time to think about how you will manage Sooty Blotch and Flyspeck in your orchard. 
Check out the New England Tree fruit management guide for more info (Sooty Blotch and Flyspeck | New England Tree Fruit Management Guide (netreefruit.org)), and remember that NEWA also provides forecasting and management recommendations for this disease complex:

From NEWA: Sooty Blotch and Flyspeck | NEWA (cornell.edu)

To effectively limit fruit finish blemishes from Sooty Blotch and Flyspeck infection consider making a cover application of one of the following fungicides/tank mixes:

Figure 1:  Recommendations from NEWA for Sooty Blotch and Flyspeck.

Insects:

SWD – Spotted Wing Drosophila:

Traps should be up now. Trap captures spiked last week in the southern half of NH. To clarify, SWD is primarily a pest of small fruits, but also impacts stone fruits. Considering the fact that most stone fruits were lost due to severe cold this winter, controlling this pest will be generally limited to very late strawberries, blueberries, brambles and grapes.

You can find more info about SWD and SWD trap selection in past pest reports, refer to the ones from this past June!

Notes of Interest:

UNH Extension is trialing red sticky traps paired with the Trece Pherocon Peel-Pak lures in 2023. We also work with many growers who use the drowning traps paired with these same lures. In the photo below, the smaller red square is the lure, while the red rectangle is the sticky trap, which gets checked weekly.

Figure 2: New red sticky traps to capture SWD. Photo: Jeremy DeLisle

SWD Netting Project

UNH Extension, USDA Natural Resources Conservation Service and the NH Conservation Districts have been partnering on a three-year demonstration project investigating the efficacy, ease of use, cost of installation and potential return on investments associated with installing SWD exclusion netting systems on three farms here in NH. Those partner farms are Bascom Road Blueberry Farm in Newport, Stark Farm in Dunbarton, and Heron Pond Farm in South Hampton. To date, the systems have been highly effective at excluding SWD flies. To learn more about the types of systems being installed and the potential for new construction versus retrofitting existing bird netting structures, join us at our upcoming twilight meeting on August 3^rd at Heron Pond Farm in South Hampton, NH. Details are available at the link at the bottom of this page.

Blueberry Maggot Fly:

Traps should be up now. Flight is expected this week if not already occurring in some locations. Details on monitoring and management can be found here.

Apple Maggot

Predicted first emergence of AM occurs after approximately 796 to 1072 degree days have accumulated. Today we have accumulated 931 DD base 50F from January 1. Set sticky traps along vulnerable field edges. Check at least weekly and not the first date of captures. Enter this into the Apple Maggot tool on NEWA.

The action threshold is an average of 1-2 AMF on the yellow cards or in unbaited sticky spheres, or a cumulative average of 5 AMF per trap on baited spheres. Trap captures for a week following insecticide treatment are ignored. Subsequent sprays can be applied once the threshold is reached again.

Figure 3: Unbaited red sticky sphere for monitoring apple maggot fly in orchards. Photo: Jeremy DeLisle

Codling moth:

We continue to catch CM in Canterbury and Concord. Below is a resource shared by Dr. Jaime Pinero at UMass outlining a control approach based on trap captures and degree day accumulations targeting larvae at egg hatch.

Traps are up and we have caught very few OBLR. Controls should be timed with egg hatch. Continue to monitor traps, establish the biofix date on your farm, and enter into the NEWA model to track development based on growing degree days.

https://newa.cornell.edu/obliquebanded-leafroller

Figure 4: Codling moth trap captures for Merrimack County

Oriental Fruit Moth

Oriental Fruit Moth (OFM) | New England Tree Fruit Management Guide (netreefruit.org)

Figure 3: Oriental Fruit Moth (OFM) trap captures for Merrimack County

Figure 5: UNH Extension Field Technician, Justin Hogg, sets up delta traps to monitor for codling moth in apple orchards. Photo: Jeremy DeLisle

San Jose Scale – Apples:

Pheromone traps should be in place to record the second adult male flight. Note date of first capture of second generation for biofix in NEWA for predicting second generation crawler emergence.

Tissue testing time is here for some crops and coming right up for others.

Directions for taking a plant tissue sample leaf sample in your orchard/garden:

Tips - In general, it is usually best to sample many plants (with only a few leaves from each plant) rather than sample many leaves from only a few plants.

Select the youngest, fully developed (mature) leaves for analysis. Do not select leaves from plants which are mechanically damaged, insect damaged, diseased or dead. Avoid leaves from border plants or leaves which are fully shaded by other foliage. Do not send sample plants that have been under prolonged stress.

Avoid leaves which are contaminated with soil or dust or which have been recently sprayed. In general, plant leaves which have been exposed to normal rainfall are sufficiently clean for analysis. Samples can be washed briefly in a 2% non-phosphorus detergent solution and then rinsed carefully with clear water. However, in many situations the cleaning may do more harm than good.

If you are trying to diagnosis a problem and are sampling plants that are showing an abnormal symptom, follow the above directions, but sample only from plants showing the problem.

Crop Information

Blueberries: sample at least 40 leaves from 10 to 20 plants during the first week of harvest.

Strawberries: sample at least 40 first fully expanded leaves from 10 to 20 plants, after renovation

Brambles: sample at least 60 leaves from 10 to 20 non-fruiting canes during early-mid August.

Grapes: sample 50 to 75 of the youngest full-expanded leaves from 10 to 20 vines at veraison (70 days after bloom, as the first fruit ripens). Separate petioles (leaf stems) from leaves, and send only the petioles for analysis.

Tree fruits: sample 5 leaves from each of 10 trees from late July through early August. Select shoots at eye-level from around the outside of the trees that make a vertical angle of 45-60 degrees to the ground (avoid water shoots or suckers). Collect leaves from the mid-portion of the new shoot growth.

For other crops: Contact your local field specialist or county office to determine the correct sampling procedures. After Collection Samples should be placed in paper bags and air dried (turn the bag frequently) or dried at 200 degrees Fahrenheit.

If you wish to submit sample to UNH for tissue sampling, more information and forms can be found here:

Form: UNH Cooperative Extension - Commercial Plant Tissue Form.pdf - All Documents (sharepoint.com)

Main soil/tissue testing site: Soil Testing Services | Extension (unh.edu)

Upcoming Events

August 3 - Blueberry IPM Twilight Meeting at Heron Pond Farm | Extension (unh.edu)

August 17^th - Tree Fruit Twilight Meeting at Apple Hill Farm | Extension (unh.edu)

See the full list of twilight meetings here:

2023 Production Agriculture Summer Twilight Meeting | Extension (unh.edu)

 Thanks for tuning in!

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Hi all!!

Welcome back to the NH Fruit Pest hotline, which is produced by staff members from the UNH Cooperative Extension Food and Agriculture team. 

While these recordings will highlight what you need to be looking for out in the field, I highly encourage you to find the transcripts online, as they will have more details and links about many of the pests, products, and models I’ll be describing in this call. Simply google “UNH Fruit pest hotline transcripts” to find them on our webpage.

In terms of growing degree days in Concord, NH we have accumulated 126 GDD in BE base 43F and 70 GDD in BE base 50F.

Home | NEWA (cornell.edu)

Lets jump right into plant pathogen updates for the apple growers.

For Apple Scab:

The 50% Macintosh green tip was established last week on 4/12 in Concord, so 4/12 is the biofix date to start using the scab model in NEWA if you are located around Concord.  Enter the date that this occurred in your orchards for the best accuracy from the model. 

Ascospores are developing slowly, with around 3% of spores expected to be discharged by the end of the predicted infection event running through Tuesday, April 18^th. More rain is predicted later in the week through Monday, April 24^th, so protection going into that stretch with a rain-fast product is advisable.

Preventative fungicides such as Captan, Mancozeb or combinations of these and similar multi-site products are good choices at this stage in the season. Captan 80 and Mancozeb at 2.5 and 3 lbs/ac respectively, reapplication if more than 1”.

 Remember that Captan and oil should not be applied within 7-10 days of one another to prevent phytotoxicity, particularly after a frost or slow drying conditions.

As we get reach pink and bloom stages with long periods of leaf wetness, consider some of the single site fungicides with the ability to translocate within leaf tissue for added control and some ability to kill very recent infections.

It is also worth noting is that some fungicides such as the groups 3, 7, 9 and 11 have activity on other fungal pathogens of controlled during this time of year, such as powdery mildew, rusts, black and white rot. Single site fungicides should be added around bloom or if several days of rain are predicted.

An excellent description of the factors to consider for best fungicide selection can be found here: https://netreefruit.org/apples/diseases/apple-scab

 For Fire Blight:

Scout for oozing cankers left in the orchard after dormant season pruning as these cankers are an indicator of ongoing infections. Copper applications between silver tip and ½’ green for reduction of overwintering fire blight bacteria (and apple scab).

NEWA’s fire blight forecasting model begins with selecting the current infection pressure from the drop-down menu in the fire blight model. Choose between the three various scenarios based on your specific conditions.

Blossom blight infection risk is tracked by the accumulation of 4-day degree hour totals beginning at bloom. NEWA begins degree hour accumulation on the date of full pink or "first blossom open" for McIntosh apple. It is best if you enter your start date based on blossom dates in your apple or pear orchards and recalculate Cougar blight risk predictions.

Typically, the first few blossoms that open are a few days ahead of true first bloom because they are close to sunny large scaffolds or trunks. Fire blight bacteria are rarely active at the very early bloom time, so getting the "first blossom open" date exact is not critical. Continue monitoring the fire blight risk predictions and watching your orchards for secondary bloom because, although infection of secondary bloom may be less dangerous than that of primary bloom, infection of secondary bloom leads to continued high disease activity and higher risk in subsequent years.

More info can be found here: Fire Blight | New England Tree Fruit Management Guide (netreefruit.org)

 Now moving onto the insect pests. 

As a reminder, much more information on these pests (including recommended chemical controls) can be found in the transcripts posted online of this call. Simply google “UNH Fruit pest hotline transcripts” to find them on our webpage.

Pear psylla:

Should be addressed early, scout for eggs on buds and leaves, new eggs light yellow, older are darker yellow. Nymphs are beginning to show up this week in NY, which is an early indicator of development for us here in NH.

Pear psylla | New England Tree Fruit Management Guide (netreefruit.org)

 San Jose Scale:

Consider the treatment of blocks where populations building. An application of dormant oil or an effective insecticide directed against the overwintering immatures under the ‘black cap’ scale covers on trunks and scaffold branches between the half-inch green and tight cluster stages will effectively reduce the potential for serious infestations later in the season. Prebloom sprays are more effective if applied dilute, at high volume; for severe infestations, follow up with summer applications of appropriate materials. Suggested action threshold: 3-6 encrusted areas per tree. SJS – Overwintering. Esteem/Centaur and oil is a good combo early.

San Jose scale (SJS) | New England Tree Fruit Management Guide (netreefruit.org)

Dogwood Borer:

Reminder that mating disruption works well for this pest. Trunk sprays are recommended between pink and mid-June.

Borers | New England Tree Fruit Management Guide (netreefruit.org)

European Red Mite:

Minimal numbers found to date. Look for overwintering eggs around the base of limbs on main trunk. Treatment windows range from greet tip to pink, and then resume after petal fall. Generally, some control before pink combined with concentrated control around petal fall will provide best season-long control.

Mites | New England Tree Fruit Management Guide (netreefruit.org)

Tarnished plant bug:

 Sticky traps should be out now, broadleaf weeds in orchard and along perimeter are common. Look for feeding damage to buds now. 3 timings beginning at TC, P, PF, pyrethroids work well.

Tarnished Plant Bug (TPB) | New England Tree Fruit Management Guide (netreefruit.org)

Red Banded Leaf Roller:

 Are laying eggs and larvae beginning to hatch in NY. RBLR causes damage at feeding sites under leaves resting on fruit.

Redbanded Leafroller [fact sheet] | Extension (unh.edu)

Codling Moth:

Currently overwintering in the pupal stage. First adult capture usually occurs at 220 DD – 50F BE. Concord is at roughly 84 DD 50 BE at the this time, so not quite there. Pheromone traps should be in place before the first apple blossoms open. Mating disruption dispensers should also be put in the orchard before the first blossoms open for seasonal disruption programs.

Codling moth (CM) | New England Tree Fruit Management Guide (netreefruit.org)

Spotted Tentiform Leaf Miner:

 Moth flight beginning. The first flight of STLM adults usually begins between the green tip and half-inch bud stage. No control measures are recommended against adults. It is very difficult to predict larval infestation levels from adult catches in pheromone traps. Sometimes catches may be very high, but if conditions are unfavorable for oviposition during the flight in the spring (cold, rainy, and windy weather), very few eggs are laid and subsequent larval populations will be low.

Leafminers (LM) | New England Tree Fruit Management Guide (netreefruit.org)

Green speckled fruit worm:

Are laying eggs and larvae beginning to hatch in NY.

Speckled green fruitworm | New England Tree Fruit Management Guide (netreefruit.org)

Oriental Fruit Moth:

 No OFM flight is expected currently. Pheromone traps and mating disruption dispensers should be deployed at the beginning of the pink bud stage.

 Oriental Fruit Moth (OFM) | New England Tree Fruit Management Guide (netreefruit.org)

 
Oblique banded leaf roller (OBLR):

 Overwintering OBLR larvae usually begin to emerge at the half-inch green growth stage. No control measures are recommended at this time because most overwintering larvae have not yet emerged and will escape residual effectiveness of most insecticides.

 Obliquebanded leafroller (OBLR) | New England Tree Fruit Management Guide (netreefruit.org)

Notes on the control of Lepidopteran Pests:

Bt (Dipel is a good choice early) can be helpful, but avoid applications during bloom.

Altacor, Exirel, Verdepryn are worth considering as control options at first hatch for codling moth. These group 28 insecticides have efficacy against many lepidopteran species as well as plum curculio. Codling moth becomes driver for insect sprays after petal fall along with plum curculio.

Rosey Apple Aphid control can start at pink. Petal fall may be best timing.

As always, refer to the tree fruit guide for more info and recommendations!

 New England Tree Fruit Management Guide | (netreefruit.org)

 One Final announcement:

 SEEKING PARTICIPANTS FOR A STATEWIDE NATIVE BEE PROJECT!

 Shyloh Favreau, a M.S. student at UNH (you may know him as the Extension Program Manager for our Soil Testing Service) is looking for apple orchards across New Hampshire to participate in his thesis project investigating the native bee communities during peak apple bloom, 2023. This project would involve a couple (4 people at most) of Extension staff and undergraduate students coming to your orchard once or twice during peak bloom to collect bees in nets and bowls with a follow up survey later in the season. Please reach out to Shyloh for more details and if you would like to participate in his study. Cell phone: 828-964-8404, Email: Shyloh.Favreau@unh.edu.

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Hi all!!

Welcome back to the NH Fruit Pest hotline, which is produced by staff members from the UNH Cooperative Extension Food and Agriculture team.   Today is April 25, 2023.

While these recordings will highlight what you need to be looking for out in the field, I highly encourage you to find the transcripts online, as they will have more details and links about many of the pests, products, and models I’ll be describing in this call. Simply google “UNH Fruit IPM Reports” to find them on our webpage or visit: https://extension.unh.edu/resource/fruit-ipm-reports

In terms of growing degree days in Concord, NH we have accumulated 222 GDD in BE base 43F and 98 GDD in BE base 50F.

Home | NEWA (cornell.edu)

Lets jump right into plant pathogen updates for the apple growers.

For Apple Scab:

The 50% Macintosh green tip was established on 4/12 in Concord, so 4/12 is the biofix date to start using the scab model in NEWA if you are located around Concord.  Enter the date that this occurred in your orchards for the best accuracy from the model. 

The rain the past few days meant that most folks around the state had an apple scab infection period over the weekend, definitely on Sunday, and NEWA predicts that infection period will extend into tomorrow, April 26^th.   Now is the time to consider if you need to spray any kickback products on your trees to address the spores released during this infection event – remember, the closer to the actual day of infection, the more effective that kickback product will be. 

An excellent description of the factors to consider for best fungicide selections can be found the New England Tree Fruit Management Guide, which can be found online at: https://netreefruit.org/apples/diseases/apple-scab

 For Fire Blight:

Right now, you want to be scouting for oozing cankers left in the orchards – these cankers indicate ongoing infections and will be a source of inoculum this spring. 

Copper applications between silver tip and ½’ green tip are used to reduce overwintering fire blight bacteria (and apple scab).

NEWA’s fire blight forecasting model begins with selecting the current infection pressure from the drop-down menu in the fire blight model. Choose between the three various scenarios based on your specific conditions at your orchard for the most accurate predictions. You will also want to input the start date of the first blossom open for your own orchards to make sure the model is accurate. 

The cooler temperatures this week mean that the fire blight infection risk is low – but remember that risk with increase significantly once the temps warm up and more blossoms open – so make sure that you have plan for infection events in the near future.

Moving on from the pathogens, and onto the insect pests:

I don’t have too many updates from last week, and just as a reminder, much more information on these pests (including recommended chemical controls) can be found in the transcripts posted online of this call. Simply google “UNH Fruit IPM Reports” to find them on our webpage.

Pear psylla:

Should be addressed early, scout for eggs on buds and leaves, new eggs light yellow, older are darker yellow. Nymphs are showing up in NY, so they are on their way.

Pear psylla | New England Tree Fruit Management Guide (netreefruit.org)

San Jose Scale:

Consider the treatment of blocks where populations are building. An application of dormant oil or an effective insecticide directed against the overwintering immatures under the ‘black cap’ scale covers on trunks and scaffold branches between the half-inch green and tight cluster stages will effectively reduce the potential for serious infestations later in the season. Prebloom sprays are more effective if applied dilute, at high volume; for severe infestations, follow up with summer applications of appropriate materials. Suggested action threshold: 3-6 encrusted areas per tree. Esteem/Centaur and oil is a good combo early.

San Jose scale (SJS) | New England Tree Fruit Management Guide (netreefruit.org)

Dogwood Borer:

Reminder that mating disruption works well for this pest. Trunk sprays are recommended between pink and mid-June.

Borers | New England Tree Fruit Management Guide (netreefruit.org)

European Red Mite:

Minimal numbers found to date. Look for overwintering eggs around the base of limbs on main trunk. Treatment windows range from greet tip to pink, and then resume after petal fall. Generally, some control before pink combined with concentrated control around petal fall will provide best season-long control.

Mites | New England Tree Fruit Management Guide (netreefruit.org)

Tarnished plant bug:

 Sticky traps should be out now, broadleaf weeds in orchard and along perimeter are common. Look for feeding damage to buds now.

Tarnished Plant Bug (TPB) | New England Tree Fruit Management Guide (netreefruit.org)

Red Banded Leaf Roller:

Are laying eggs and larvae beginning to hatch in NY. RBLR causes damage at feeding sites under leaves resting on fruit.

Redbanded Leafroller [fact sheet] | Extension (unh.edu)

Codling Moth:

Currently overwintering in the pupal stage. First adult capture usually occurs at 220 DD – 50F BE. Concord is at roughly 98 DD 50 BE at the this time, so not quite there. Pheromone traps should be in place before the first apple blossoms open. Mating disruption dispensers should also be put in the orchard before the first blossoms open for seasonal disruption programs.

Codling moth (CM) | New England Tree Fruit Management Guide (netreefruit.org)

Spotted Tentiform Leaf Miner:

 Moth flight beginning. The first flight of STLM adults usually begins between the green tip and half-inch bud stage. No control measures are recommended against adults. It is very difficult to predict larval infestation levels from adult catches in pheromone traps. Sometimes catches may be very high, but if conditions are unfavorable for oviposition during the flight in the spring (cold, rainy, and windy weather – just like we had this week!), very few eggs are laid and subsequent larval populations will be low.

Leafminers (LM) | New England Tree Fruit Management Guide (netreefruit.org)

Green speckled fruit worm:

Are laying eggs and larvae beginning to hatch in NY.

Speckled green fruitworm | New England Tree Fruit Management Guide (netreefruit.org)

Oriental Fruit Moth:

 No OFM flight is expected currently. Pheromone traps and mating disruption dispensers should be deployed at the beginning of the pink bud stage.

 Oriental Fruit Moth (OFM) | New England Tree Fruit Management Guide (netreefruit.org)

 Oblique banded leaf roller (OBLR):

 Overwintering OBLR larvae usually begin to emerge at the half-inch green growth stage. No control measures are recommended at this time because most overwintering larvae have not yet emerged and will escape residual effectiveness of most insecticides.

 Obliquebanded leafroller (OBLR) | New England Tree Fruit Management Guide (netreefruit.org)

 That’s all that I have for the hotline this week!

As always, refer to the tree fruit guide for more info and recommendations:

 New England Tree Fruit Management Guide | (netreefruit.org)

 See you all next week!

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Hi all!!  

 Welcome back to the NH Fruit Pest hotline, which is produced by staff members from the UNH Cooperative Extension Food and Agriculture team.   Today is May 2^nd, 2023.

 While these recordings will highlight what you need to be looking for out in the field, I highly encourage you to find the transcripts online, as they will have more details and links about many of the pests, products, and models I’ll be describing in this call. Simply google “UNH Fruit pest hotline transcripts” to find them on our webpage. 

 In terms of growing degree days in Concord, NH we have accumulated 191 GDD in BE base 43F and 73 GDD in BE base 50F.

Lets jump right into plant pathogen updates for the apple growers.

Apple scab:

 The 50% Macintosh green tip date was established on 4/12 in Concord. This is the biofix to start the apple scab model in NEWA. Enter the date that this occurred in your orchards for the best accuracy from the model. Ascospores are developing slowly under these cool conditions, with around 31% of spores expected to be discharged by the end of the predicted infection event running through Thursday, May 4^th. The forecast currently shows a break in the rain by the afternoon of May 4^th. This will be a good time to reapply fungicides and possibly use one of the materials with kickback activity depending on how well you were going into this rainy stretch and your scab pressure from last season.

Preventative fungicides such as Captan, Mancozeb or combinations of these and similar multi-site products are good choices at this stage in the season. Captan 80 and Mancozeb at 2.5 and 3 lbs/ac respectively, reapplication if more than 1”. Consider mixing these materials with a single site fungicide from group 3 as we approach pink into bloom, as this is when the maximum amount of ascospores are released. With warmer temperatures coming in on Saturday, May 6^th, a wetting event will require fewer hours to cause an infection. Hopefully we will start to dry out in time for bloom in most locations.

As we get reach pink and bloom stages with long periods of leaf wetness, consider some of the single site fungicides with the ability to translocate within leaf tissue for added control and some ability to kill very recent infections. An excellent description of the factors to consider for best fungicide selection can be found here: https://netreefruit.org/apples/diseases/apple-scab

 Marssonina (Apple Blotch):

While we are currently in the first half of apple scab season, you should remember that this fungus is also a concern and can be controlled with many of the same fungicides that control apple scab. The period of main concern is really at the tail end of apple scab season, but be aware and read up here about when and how to best control it.

2023 Disease Update: Disease Conditions Favored for Marssonina Blotch and Apple Scab April 28–May 1 (psu.edu)

Fire blight:

Remember that using the fireblight model in NEWA begins with selecting the current infection pressure from the drop-down menu in the fireblight model. Choose between the three various scenarios based on your specific conditions.

Blossom blight infection risk is tracked by the accumulation of 4-day degree hour totals beginning at bloom. NEWA begins degree hour accumulation on the date of full pink or "first blossom open" for McIntosh apple. It is best if you enter your start date based on blossom dates in your apple or pear orchards and recalculate Cougarblight risk predictions.

Typically, the first few blossoms that open are a few days ahead of true first bloom because they are close to sunny large scaffolds or trunks. Fire blight bacteria are rarely active at the very early bloom time, so getting the "first blossom open" date exact is not critical. Continue monitoring the fire blight risk predictions and watching your orchards for secondary bloom because, although infection of secondary bloom may be less dangerous than that of primary bloom, infection of secondary bloom leads to continued high disease activity and higher risk in subsequent years.

Reports from southern NH indicate that the first king blossoms on early varieties such as Zestar! are just barely starting to open as of May 1. Pay attention to those Macintosh trees as we enter the beginning of next week to get an accurate date for the biofix for this model in NEWA. Temperatures will be just warm enough by the middle of next week to start paying attention for infection events. One good thing about this cool weather is that it has ruled out fireblight infections up until now. Next week we should start to pay attention in earnest.

Fire Blight | New England Tree Fruit Management Guide (netreefruit.org)

 Powdery mildew:

Dry periods during scab season can be a prime time for infection by powdery mildew. Group 3 fungicides used for scab control will also control PM. Consider saving the group 11 fungicides until petal fall for control of summer diseases.

Powdery Mildew | New England Tree Fruit Management Guide (netreefruit.org)

 Now moving onto the insect pests:

Tarnished Plant Bug:

Tarnished Plant Bug captures in white sticky traps have remained very low. Numbers have been suppressed due to cold temperatures.

Tarnished Plant Bug (TPB) | New England Tree Fruit Management Guide (netreefruit.org)

Oriental Fruit Month:

 Pheromone traps and mating disruption dispensers should be deployed at the beginning of the pink bud stage. The first catch of moths from the overwintering generation is expected to be soon. Flight of OFM usually begins when trees are in the pink or bloom bud stages. No insecticides need to be applied until eggs begin to hatch; since OFM flight usually begins at bloom, it is not possible to apply an initial spray to kill adults.

 Oriental fruit moth (OFM) | New England Tree Fruit Management Guide (netreefruit.org)

 Oblique banded Leaf roller and Red Banded Leaf Roller:

high numbers in NY. This isn’t necessarily an indicator of what we will see in NH, but we should have our traps out and eyes open.

Obliquebanded leafroller (OBLR) | New England Tree Fruit Management Guide (netreefruit.org)

Redbanded Leafroller [fact sheet] | Extension (unh.edu)

For the Oblique banded Leaf roller, almost all overwintering larvae have emerged by the end of the pink bud stage. Overwintering larvae can be sampled starting at the pink bud stage. A control spray can be applied during pink if larval populations exceed a threshold of 3% clusters infested with live larvae.

Codling Moth:

The average 1^st catch 475 DD base 43, mating disruption with granulosis virus is a good option, Altocor for 1^st gen, Assail for 2^nd gen will also control apple maggot. Altacor, Exirel, Verdepryn are worth considering as control options at first hatch for codling moth. These group 28 insecticides have efficacy against many lepidopteran species as well as plum curculio. Codling moth becomes the driver for insect sprays after petal fall along with plum curculio.

Codling moth (CM) | New England Tree Fruit Management Guide (netreefruit.org)

In General:

Bt (Dipel is a good choice early) in the development of lepidopteran pests. Avoid applications during bloom.

Rosey Apple Aphid:

Control can start at pink. Petal fall may be best timing.  Be scouting now to be aware of possible aphid hot spots.

Aphid: Rosy Apple Aphid | New England Tree Fruit Management Guide (netreefruit.org)

European Red Mite:

Look for overwintering eggs now. Treatment windows range from green tip to pink, and then resume after petal fall. Generally, some control before pink combined with concentrated control around petal fall will provide best season-long control.

Mites (European Red Mite [ERM] and Two-spotted Spider Mite [TSSM]) | New England Tree Fruit Management Guide (netreefruit.org)

 Finally:

We received a question recently about boron applications for apples. This is an important nutrient for apples for pollen tube development, feeder root growth and translocation of calcium, among other functions. Details about the roles of various macro and micronutrients in apples can be found here: http://fruitadvisor.info/tfruit/clements/articles/nutrientrecs.pdf

 Thank you for sticking around until the very end!  See you next week!

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Hi all!!  

 Welcome back to the NH Fruit Pest hotline, which is produced by staff members from the UNH Cooperative Extension Food and Agriculture team.   Today is May 9^th , 2023.

While these recordings will highlight what you need to be looking for out in the field, I highly encourage you to find the transcripts online, as they will have more details and links about many of the pests, products, and models I’ll be describing in this call. Simply google “UNH Fruit IPM reports” to find them on our webpage. The transcript for this call may not be up until Wednesday afternoon.

In terms of growing degree days in Concord, NH we have accumulated 347 GDD in BE base 43F and 159 GDD in BE base 50F.

Lets jump right into plant pathogen updates for the apple growers.

Apple scab:

With all of that rain we got last week, most of you probably got a spray on last week, and potentially with a kickback product and a multisite spray.  This upcoming week we are drying out a bit and NEWA is not showing any infection events, but remain vigilant and keep an eye out for any lesions on the leaves that could be forming from the infection events we had last week.  Remember that this time of year can be tricky with the rapidly expanding leaves and getting the right amount of coverage to combat the apple scab – spray as close as you can to infection events to cover the most surface area of the leaves as possible.

As always, when using NEWA, make sure you are putting  in the most accurate green tip date and weather station into the models to get the most accurate predictions for your orchard.

Refer to the New England Tree Fruit Guide more information: https://netreefruit.org/apples/diseases/apple-scab

Marssonina (Apple Blotch):

This is a bit of a newcomer in this area but this fungal pathogen is also a concern and can be controlled with many of the same fungicides that control apple scab. The period of main concern is really at the tail end of apple scab season, but be aware and read up here about when and how to best control it.

2023 Disease Update: Disease Conditions Favored for Marssonina Blotch and Apple Scab April 28–May 1 (psu.edu)

Fire blight:

Remember that using the fireblight model in NEWA begins with selecting the current infection pressure from the drop-down menu in the fireblight model. Choose between the three various scenarios based on your specific conditions.

Blossom blight infection risk is tracked by the accumulation of 4-day degree hour totals beginning at bloom. NEWA begins degree hour accumulation on the date of full pink or "first blossom open" for McIntosh apple. It is best if you enter your start date based on blossom dates in your apple or pear orchards and recalculate Cougarblight risk predictions.

The MacIntosh trees in the concord area are blooming, so now is the time to be ready for fire blight infection events.

If your orchard has a history of fire blight infections in previous years, the models show that you have a moderate/high risk for a fire blight infection this week, especially as we get towards the end of the week (around Friday May 12^th).  This is because there are probably some lingering cankers in your orchards that will produce the next round of bacteria to infect your trees if they are not treated properly. If you don’t have a history of fire blight, your risk is lower this week.  Be sure to check out NEWA’s forecast and set the parameters for your specific orchards.

If you are interested in using SAR, or Systemic Acquired Resistance products, now could be a good time to apply those ahead of the infection event. These materials get the trees to activate their own defenses against fire blight ahead of the infection event and can be a good “tool in the toolbox” to fight fire blight in your orchards.  SAR products include Actigard, Lifegard and others.  Check out the New England Tree fruit guide for more info!

Fire Blight | New England Tree Fruit Management Guide (netreefruit.org)

Powdery mildew:

Dry periods during scab season can be a prime time for infection by powdery mildew. Group 3 fungicides used for scab control will also control PM. Consider saving the group 11 fungicides until petal fall for control of summer diseases.

Powdery Mildew | New England Tree Fruit Management Guide (netreefruit.org)

Related Disease note:

Blueberry growers: if the fungal pathogen mummy berry is present in your fields (essentially if you had problems with it last year) it was probably sporulating last week/into this week with that rainy weather we had.  Keep an eye out for the symptoms if you have had issues with it in the past.

For more info, check out:

Over-informed on IPM - Episode 020: Mummy berry and Pollinator Protection | Extension (unh.edu)

Now moving onto the insect pests:

Just a reminder: With bloom, no insecticide sprays should be going out to protect our native pollinators!

Tarnished Plant Bug:

Tarnished Plant Bug captures in white sticky traps have remained very low. Numbers have been suppressed due to cold temperatures.  Be sure to have your traps out.

Tarnished Plant Bug (TPB) | New England Tree Fruit Management Guide (netreefruit.org)

Oriental Fruit Month:

Pheromone traps and mating disruption dispensers should be deployed now. The first catch of moths from the overwintering generation is expected to be soon but none have been caught as of last week. No insecticides need to be applied until eggs begin to hatch; since OFM flight usually begins at bloom, it is not possible to apply an initial spray to kill adults.

Oriental fruit moth (OFM) | New England Tree Fruit Management Guide (netreefruit.org)

Oblique banded Leaf roller and Red Banded Leaf Roller:

No Oblique banded Leaf rollers caught as of last week.  We did catch a single Red Banded Leaf Roller, but no biofix date for that yet.

Obliquebanded leafroller (OBLR) | New England Tree Fruit Management Guide (netreefruit.org)

Redbanded Leafroller [fact sheet] | Extension (unh.edu)

Codling Moth:

No captures yet. The average 1^st catch 475 DD base 43, mating disruption with granulosis virus is a good option, Altocor for 1^st gen, Assail for 2^nd gen will also control apple maggot. Altacor, Exirel, Verdepryn are worth considering as control options at first hatch for codling moth. These group 28 insecticides have efficacy against many lepidopteran species as well as plum curculio. Codling moth becomes the driver for insect sprays after petal fall along with plum curculio.

Codling moth (CM) | New England Tree Fruit Management Guide (netreefruit.org)

In General:

Bt (Dipel is a good choice early) in the development of lepidopteran pests. Avoid applications during bloom.

Rosey Apple Aphid:

Control can start at pink. Petal fall may be best timing.  Be scouting now to be aware of possible aphid hot spots.

Aphid: Rosy Apple Aphid | New England Tree Fruit Management Guide (netreefruit.org)

European Red Mite:

Look for overwintering eggs now. Treatment windows range from green tip to pink, and then resume after petal fall. Generally, some control before pink combined with concentrated control around petal fall will provide best season-long control.

Mites (European Red Mite [ERM] and Two-spotted Spider Mite [TSSM]) | New England Tree Fruit Management Guide (netreefruit.org)

Additional Notes:

We received a question recently about boron applications for apples. This is an important nutrient for apples for pollen tube development, feeder root growth and translocation of calcium, among other functions. Details about the roles of various macro and micronutrients in apples can be found here: http://fruitadvisor.info/tfruit/clements/articles/nutrientrecs.pdf

Twilight Meetings:

The schedule is out for all of extension’s summer twilight meetings, and I wanted to highlight a few that may be of interest to the folks that tune into this call – the full list of Extensions event offerings this summer can be found on our website!

Tree Fruit meeting at Demeritt Hill Farm, July 15^th, 2023 5:30-7:30 pm

Tree Fruit Twilight Meeting at DeMerritt Farm | Extension (unh.edu)

Tree Fruit meeting at Apple Hill Farm, August 17^th, 2023 5:30-7:30 pm

Tree Fruit Twilight Meeting at Apple Hill Farm | Extension (unh.edu)

All of the Production agriculture Twilight meetings:

2023 Production Agriculture Summer Twighlight Meeting | Extension (unh.edu)

Thank you for sticking around until the very end!  See you next week!

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Hi all!!  

 Welcome back to the NH Fruit Pest hotline, which is produced by staff members from the UNH Cooperative Extension Food and Agriculture team.   Today is May 16^th , 2023.

While these recordings will highlight what you need to be looking for out in the field, I highly encourage you to find the transcripts online, as they will have more details and links about many of the pests, products, and models I’ll be describing in this call. Simply google “UNH Fruit IPM reports” to find them on our webpage. The transcript for this call may not be up until Wednesday afternoon.

In terms of growing degree days in Concord, NH we have accumulated 439 GDD in BE base 43F and 161 GDD in BE base 50F.

Frost:  Potential for Frost Wednesday night (5/17) across most of the state.  Strawberries and potentially blueberries could be at risk of frost damage.  Frost protection measures should be taken, especially for the early strawberry varieties!

Lets jump right into plant pathogen updates for the apple growers.

Apple scab:

When using NEWA, make sure you are putting in the most accurate green tip date and weather station into the models to get the most accurate predictions for your orchard.  My predictions are based off of the concord weather station, with April 12^th as the biofix date.

Keep an eye out for any lesions from past infection events on your leaves.

Ascospores are developing slowly under these cool conditions, with 84% of ascospores mature and awaiting our next rain event. The forecast currently shows potential rain on Friday and Saturday, May 19th and 20th. Thursday, May 18^th looks dry with low winds, so consider making a fungicide application then. This is the time to use your more effective systemic materials along with a multisite such as Captan or Mancozeb. FRAC group 7 fungicides are preferred during this time of peak scab activity.

Details on rotational options with other FRAC groups can be found here: https://extension.psu.edu/2023-disease-update-scab-and-fire-blight-infections-forecasted-for-the-weekend

As we progress through the pink and bloom stages across the state, consider some of the single site fungicides with the ability to translocate within leaf tissue for added control and some ability to kill very recent infections. An excellent description of the factors to consider for best fungicide selection can be found here: https://netreefruit.org/apples/diseases/apple-scab

Marssonina (Apple Blotch):

This is a bit of a newcomer in this area but this fungal pathogen is also a concern and can be controlled with many of the same fungicides that control apple scab. The period of main concern is really at the tail end of apple scab season, but be aware and read up here about when and how to best control it.

2023 Disease Update: Disease Conditions Favored for Marssonina Blotch and Apple Scab April 28–May 1 (psu.edu)

Fire blight:

Much of the state is in bloom with apples and pears ranging from late pink to petal fall depending on location and variety. We had infection events on May 11,12 and 13. Many growers elected to make a streptomycin application during that timeframe. Those who have experienced high fire blight pressure in recent years may also have included Apogee/Kudos to slow down shoot development and thicken cell walls to prevent against infection. They may also have applied and/or continue to apply the SARs (systemic acquired resistance) inducers Actigard or Regalia.

More information about the use of PGRs and SARs can be found here: Applying Apogee and Actigard to young apple trees - Apples (msu.edu)

As well as here: Fire Blight | New England Tree Fruit Management Guide (netreefruit.org)

The take home message is that blossoms that have opened since your last application need to be covered with your material of choice. Continue to watch the weather forecast and cross-reference NEWA to best time applications.

Using the fire blight model in NEWA begins with selecting the current infection pressure from the drop-down menu in the fire blight model. Choose between the three various scenarios based on your specific conditions.

Note about the NEWA Models for fire blight:

Blossom blight infection risk is tracked by the accumulation of 4-day degree hour totals beginning at bloom. NEWA begins degree hour accumulation on the date of full pink or "first blossom open" for McIntosh apple. It is best if you enter your start date based on blossom dates in your apple or pear orchards and recalculate Cougarblight risk predictions.

Typically, the first few blossoms that open are a few days ahead of true first bloom because they are close to sunny large scaffolds or trunks. Fire blight bacteria are rarely active at the very early bloom time, so getting the "first blossom open" date exact is not critical. Continue monitoring the fire blight risk predictions and watching your orchards for secondary bloom because, although infection of secondary bloom may be less dangerous than that of primary bloom, infection of secondary bloom leads to continued high disease activity and higher risk in subsequent years.

Powdery mildew:

Dry periods during scab season can be a prime time for infection by powdery mildew. Group 3 fungicides used for scab control will also control PM. Consider saving the group 11 fungicides until petal fall for control of summer diseases.

Powdery Mildew | New England Tree Fruit Management Guide (netreefruit.org)

Now moving onto the insect pests:

Just a reminder: With bloom, no insecticide sprays should be going out to protect our native pollinators!

Plum curculio:

Control typically begins at petal fall with a whole block spray, followed by 1 or 2 perimeter row sprays depending on the weather and progression of this insect through its’ life cycle. Egg laying typically stops around 308 degree days after petal fall, at which time the need for targeted control generally stops. With this season progressing slowly so far with these cool temperatures, we are gaining degree days slowly. This means that the egg laying period for PC may be extended unless the temperatures drastically warm up.  Some southern NH orchards already have fruit at a susceptible stage for PC damage, as the insect prefers fruit at the 3-5 mm size for egg laying. Temperatures this week will certainly be warm enough for PC activity, so blocks of trees that are past petal fall should be protected.

Plum curculio (PC) | New England Tree Fruit Management Guide (netreefruit.org)

Tarnished Plant Bug:

Tarnished Plant Bug captures in white sticky traps have remained very low. Numbers have been suppressed due to cold temperatures. We have yet to capture our first TPB in Concord or Lebanon

Tarnished Plant Bug (TPB) | New England Tree Fruit Management Guide (netreefruit.org)

Oriental Fruit Month:

Pheromone traps and mating disruption dispensers should be deployed now. The first catch of moths from the overwintering generation is expected to be soon but none have been caught in our traps. OFM flight usually begins when trees are in the pink or bloom stage. No insecticides need to be applied until eggs begin to hatch; since OFM flight usually begins at bloom, it is not possible to apply an initial spray to kill adults.

Oriental fruit moth (OFM) | New England Tree Fruit Management Guide (netreefruit.org)

Oblique banded Leaf roller and Red Banded Leaf Roller:

No updates on trap numbers of there, but note that the emergence of overwintering larvae is typically completed by the end of bloom.

Obliquebanded leafroller (OBLR) | New England Tree Fruit Management Guide (netreefruit.org)

Redbanded Leafroller [fact sheet] | Extension (unh.edu)

Codling Moth:

In Concord we have yet to establish the biofix to start the codling moth model within NEWA. The biofix was established on Friday, May 12^th in Belchertown, MA. Traps should be up and monitored daily in order to best track the development of this insect. Once sustained trap captures have been observed, enter the biofix date for your farm into the NEWA model to track development of the pest as egg laying approaches.

Altacor, Exirel, Verdepryn are worth considering as control options at first hatch for codling moth. These group 28 insecticides have efficacy against many lepidopteran species as well as plum curculio. CM becomes driver for insect sprays after petal fall along with plum curculio.

Codling moth (CM) | New England Tree Fruit Management Guide (netreefruit.org)

Rosey Apple Aphid:

Control can start at pink. Petal fall may be best timing.  Be scouting now to be aware of possible aphid hot spots.

Aphid: Rosy Apple Aphid | New England Tree Fruit Management Guide (netreefruit.org)

European Red Mite:

Look for overwintering eggs now. Treatment windows range from green tip to pink, and then resume after petal fall. Generally, some control before pink combined with concentrated control around petal fall will provide best season-long control.

Mites (European Red Mite [ERM] and Two-spotted Spider Mite [TSSM]) | New England Tree Fruit Management Guide (netreefruit.org)

Additional Notes:

Thinning

The opportunity to thin potential fruit load begins at bloom and lasts until 3-4 weeks post petal fall. Consider using the Carbohydrate Thinning Model in NEWA to help make the best thinning management decisions based on factors such as localized weather patterns and other site-specific factors. This UMass resource outlines the best options and key considerations for chemical thinning: Fruit: HRT-Thinning Apples Chemically | Center for Agriculture, Food, and the Environment at UMass Amherst

We received a question recently about boron applications for apples. This is an important nutrient for apples for pollen tube development, feeder root growth and translocation of calcium, among other functions. Details about the roles of various macro and micronutrients in apples can be found here: http://fruitadvisor.info/tfruit/clements/articles/nutrientrecs.pdf

Upcoming meetings:

Carbon Capture for Agricultural Producers (Online): Thursday May 18^th, 5:30-7:30 p.m.

Details here: Carbon Capture Seminar for Agricultural Producers | Extension (unh.edu)

RMA Apple Insurance Listening Session:

June 27, 2023 : Goffstown, New Hampshire

10:00 a.m. to 12:00 p.m., Hillsborough County Extension Office (Large Conference Room)

329 Mast Rd., Goffstown, NH 03045

No RSVP required.

Details here: Summer 2023 Apple Grower Meetings | RMA (usda.gov)

Twilight Meetings:

The schedule is out for all of extension’s summer twilight meetings, and I wanted to highlight a few that may be of interest to the folks that tune into this call – the full list of Extensions event offerings this summer can be found on our website!

Tree Fruit meeting at Demeritt Hill Farm, July 15^th, 2023 5:30-7:30 pm

Tree Fruit Twilight Meeting at DeMerritt Farm | Extension (unh.edu)

Tree Fruit meeting at Apple Hill Farm, August 17^th, 2023 5:30-7:30 pm

Tree Fruit Twilight Meeting at Apple Hill Farm | Extension (unh.edu)

All of the Production agriculture Twilight meetings:

2023 Production Agriculture Summer Twighlight Meeting | Extension (unh.edu)

Thank you for sticking around until the very end!  See you next week!

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Hi all!!  

 Welcome back to the NH Fruit Pest hotline, which is produced by staff members from the UNH Cooperative Extension Food and Agriculture team.   Today is May 30^th , 2023.

While these recordings will highlight what you need to be looking for out in the field, I highly encourage you to find the transcripts online, as they will have more details and links about many of the pests, products, and models I’ll be describing in this call. Simply google “UNH Fruit IPM reports” to find them on our webpage. The transcript for this call may not be up until Wednesday afternoon.

In terms of growing degree days in Concord, NH we have accumulated 634 GDD in BE base 43F and 260 GDD in BE base 50F.

Lets dive into the frost event everyone has been talking about:

The frost event that occurred very late Wednesday, May 17^th and into the late morning hours of May 18^th caused extensive and quite variable damage across New Hampshire farms. While we had already lost our peach crop back on a single night in February, apples, pears, blueberries, strawberries and grapes were relatively undamaged until last week. While initial assessments are still underway, and damage varies considerably across locations and varieties, there was significant damage to apples, blueberries, and unprotected strawberries. We are not as certain about grapes and brambles at this point, but some potential damage is expected. Producers should document damage, contact their insurance providers, and connect with their Extension specialists to evaluate and document damage, and develop appropriate IPM plans for the season based on the situation at their specific locations.

I’ll jump into frost damage control/considerations first:

Managing berry planting after frost: (*Northeast Berry Call Recommendations – thanks to all the folks offering advice to the region!)

Pest control:

Plantings with total fruit loss still need to be actively managed for pests and weeds. Potential for botrytis is greater in all affected berries with dead tissue on the plant (black strawberry blossoms, blighted tips of blueberry canes, black bramble flowers). It would be a good idea to spray now for botrytis, especially in strawberries. Other fungal pathogens don’t live in dead tissue as botrytis does, so we only worry about botrytis.

Pruning:

In bush and cane-berries that have a big percentage of crop lost, anticipate summer thinning because extra energy will be allocated to vegetative growth. Perhaps due to the lost crop this year, next year’s crop will be larger.

June-bearing strawberry plantings should not be renovated now if they had total crop loss. They should be renovated in July or August as usual. Additional Nitrogen applications may be helpful in the case of total crop loss by helping the plants put on biomass. Crowns should be cut in half and checked for damage from frost. Depending on the degree of damage there, may have diminishing returns on inputs.

Watering:

Plantings should be watered to minimize drought stress. This might help remaining fruit recover instead of senescing.

Fertility:

 At this point in the season most blueberries have had 1 round of fertilizer applied already. A second round of fertilizer at this point in the season is important because it helps set the fruiting buds. Foliar nutrient sprays are popular amongst growers. Some have seen good results from Megafol (3-0-8). Some growers do 2 applications at a pint/acre each (mid-April and post-bloom), while others do 1 big application at 1 quart/acre each. Some growers also spray potassium on blossoms and developing fruit for winter protection. This is especially done in apples, sometimes on raspberries too. The K+ (potassium) ions prevent the growth of ice-nucleating bacteria; copper sprays work too.

Managing tree fruit after frost (Advice from Terence Bradshaw, UVM Extension)

This is just a quick recap, please check out his full post: VT Apple IPM: Management in light of a difficult crop situation – UVM Fruit Blog

Thinning:

·      For orchards that have no fruit or heavily damaged fruits (+ 75% ) do not consider thinning this year.

·      For orchards with less than 20%, consider thinning as normal this year.

·      For orchards that have moderate damage between 25 and 75%, the answer is a bit more site-specific. Not thinning those orchards may result in heavy set of small fruit that could promote biennialism, but trees are likely to respond well to thinners applied in the next week, given both the cold damage and the warm sunny, weather that we are expecting coming up.

·      At the UVM Orchard, which experienced moderate fruit damage between 20 and 70%, depending upon cultivar, they decided to apply a low rate of NAA thinner with a low rate of carbaryl insecticide. They have 70 varieties across the whole orchard, and it is difficult to thin based upon variety even in a ‘normal’ year, which is not too different from what many other retail orchards might be dealing with.  It is difficult to provide blanket recommendations to growers given the state of the crop this year.

·      In the end, Dr. Bradshaw recommends trusting your gut – if you have a good crop thin it, if you have a moderate crop consider thinning it lightly as you could always come back in later next week and be better able to visualize the effects of both the frost and any thinner applications you may have applied.

Full post: VT Apple IPM: Management in light of a difficult crop situation – UVM Fruit Blog

More on thinning:

The opportunity to thin potential fruit load begins at bloom and lasts until 3-4 weeks post petal fall. Consider using the Carbohydrate Thinning Model in NEWA to help make the best thinning management decisions based on factors such as localized weather patterns and other site-specific factors. This UMass resource outlines the best options and key considerations for chemical thinning: Fruit: HRT-Thinning Apples Chemically | Center for Agriculture, Food, and the Environment at UMass Amherst

Insect management:  (Advice from Terence Bradshaw, UVM Extension)

This is just a quick recap, please check out his full post: VT Apple IPM: Management in light of a difficult crop situation – UVM Fruit Blog

·      This will differ depending upon the state of the crop in your orchard.

·      For orchards with a full or even a moderate crop, plan to manage your insect pests as normal this year. Petal fall insecticide sprays should have already gone on in most orchards.

·      Normally petal fall sprays are targeted at European apple sawfly, early emerging codling moth, and plum curculio. All of those pests are fruit feeders so orchards that have no fruit or are assumed to have very little fruit may consider omitting all insecticide applications targeted toward protecting fruit.

·      The difficult situation comes where orchards have a low set of fruit where the expense of the application on a per bushel basis could be quite high but the value of the few apples you have is also high. If there's any question about whether or not you have sufficient crop set in your orchard, it is recommended to go ahead and treat as usual. If you have no crop or nearly no crop, then you may consider omitting those insecticides.

·      However, it is worth it to consider maintaining some coverage primarily for shoot and leaf feeding, lepidopterous caterpillar larvae. That may mean including BT sprays in petal fall, scab, thinning, or other sprays in order to keep down leps like the obliquebanded leaf roller and tent caterpillar.

·      In orchards with little to no crop, the great reduction insecticides used this year may allow beneficial populations to increase substantially, setting you up for a better IPM program next year.

·      It is not recommended to ignore trunk applications of Assail or another appropriate insecticide in young plantings to avoid issues with dogwood and other borers.

Full post: VT Apple IPM: Management in light of a difficult crop situation – UVM Fruit Blog

Nutrients:  :  (Advice from Terence Bradshaw, UVM Extension)

This is just a quick recap, please check out his full post: VT Apple IPM: Management in light of a difficult crop situation – UVM Fruit Blog

·      For trees with normal or moderate crop load, fertilize as you normally would.

·      For trees with little to no crop nitrogen applications should not go on this year unless trees are under-vigorous.

·      For trees with little to no crop this year potassium is not likely to be removed in any significant amount because that is usually removed in harvested fruit. However, it is important to maintain or improve the potassium status in your orchards to ensure that you have an appropriate amount of that nutrient going into next year when it is likely that orchards will have a heavy crop load.

·      He does recommend thinking about applying magnesium potassium fertilizers in the next month or so regardless of crop status.

Included below are some other great resources you may find helpful:

Apple Thinning Recommendations After the Frost: A Case-by-Case Scenario – Wisconsin Fruit

After the Freeze 2020 | Purdue University Facts for Fancy Fruit

Disease management after bad frost events? – Virginia Grape Disease Updates (grapepathology.org)

Strawberry Disease Management | Purdue University Facts for Fancy Fruit

Jumping into the plant pathogen updates:

Apple scab:

We are now essentially in the very tail end of primary scab season. All but the very last of the ascospores should be release with the next rain. Maintain protection and continue to scout over the next couple of weeks. Hopefully your orchard is clean of scab and this will mean the end of required control measures for the growing season.

An excellent description of the factors to consider for best fungicide selection can be found here: https://netreefruit.org/apples/diseases/apple-scab

Marssonina (Apple Blotch):

While we are currently in the tail end of primary apple scab season, you should remember that this fungus is also a concern and can be controlled with many of the same fungicides that control apple scab. The period of main concern is really at the tail end of apple scab season, but be aware and read up here about when and how to best control it. Keep an eye on any brown lesions beginning to form on your leaves – could be apple scab, could be marssonina!  Apple scab resistant  varieties tend to be the most susceptible to marssonina.

Fire Blight:

Much of the state is past bloom with apples and pears ranging from late bloom to fruit set depending on location and variety. Check the NEWA models for infection risk in relation to the crop development stage at your orchard. Continue to watch the weather forecast and cross-reference NEWA to best time applications.

Important: Any open blossoms still on trees should be considered vulnerable to infection from fireblight.

Fire Blight | New England Tree Fruit Management Guide (netreefruit.org)

Now is the time to scout for shoot strikes. 1-2 weeks after petal fall, scout orchards for shoot blight, including rootstock sucker infections. Prune and remove infected shoots 12 inches below the infected margin during cool, dry weather.

Pruning is particularly useful when blossom blight is well controlled and canker blight infections are thus the main source of inoculum for disease spread during the summer. Pruning can help limit disease spread, but will be most effective if practiced rigorously during the first few weeks after bloom; pruning will do little to slow disease spread if delayed until a large number of infections are visible.

Routine use of antibiotics to prevent shoot blight spread during the summer is not effective or recommended. However, applications to protect new wounds immediately following a hailstorm can be very beneficial; check current recommendations.

Powdery mildew:

Dry periods during scab season can be a prime time for infection by powdery mildew. Group 3 fungicides used for scab control will also control PM. Consider saving the group 11 fungicides until petal fall for control of summer diseases. Sulfur is also a good choice for PM control in conventional and organic orchards. This week may be the best opportunity to control PM, so consider choosing a fungicide with good efficacy against both this disease and scab.

Powdery Mildew | New England Tree Fruit Management Guide (netreefruit.org)

Insects:

Plum curculio:          

In Concord the petal fall date we are using is 5/19/23. From that date, we have accumulated 117 degree days base 50F, and are predicted to have accumulated 198 DD by Sunday, June 4^th.

Control typically begins at petal fall with a whole block spray, followed by 1 or 2 perimeter row sprays depending on the weather and progression of this insect through its’ life cycle. Egg laying typically stops around 308 degree days after petal fall, at which time the need for targeted control generally stops. With this season progressing slowly so far with these cool temperatures, we are gaining degree days slowly. This means that the egg laying period for PC may be extended unless the temperatures drastically warm up.  Some southern NH orchards already have fruit at a susceptible stage for PC damage, as the insect prefers fruit at the 3-5 mm size for egg laying. Temperatures this week will certainly be warm enough for PC activity, so blocks of trees that are past petal fall should be protected. While few egg laying scars have been found while scouting orchards, Plum curculio will certainly be active this week.

Plum curculio (PC) | New England Tree Fruit Management Guide (netreefruit.org)

Codling moth:

In Canterbury we finally established the biofix date of 5/26/23 to start the codling moth model within NEWA. We will now reduce the frequency of trap checking for this insect to once a week. Once sustained trap captures have been observed, enter the biofix date for your farm into the NEWA model to track development of the pest as egg laying approaches. You would need to be trapping yourself to have the most accurate date for your farm.

Southern NH established the biofix of codling moth as of 5/22/23. Southern growers without traps on their farms could enter this date to start the degree day clock running for egg hatch by this pest, which is expected at 220 –250 DD base 50F from sustained catch.

Codling moth (CM) | New England Tree Fruit Management Guide (netreefruit.org)

Interested in more details on how degree days are used to inform codling moth management practices?

Cornell has a wonderful fact sheet that talks about this, check out the quick summary below or check out the entire resource at this link: doc_72.pdf (cornell.edu)

Time insecticide applications based on trap data and degree day (DD) models for egg hatch. Spray timing for these pests is directed at newly hatched larvae, since most insecticides are not effective at controlling adults. There is a lag period for egg hatch after the moths fly. The first spray for CM is recommended at first egg hatch, which occurs 220-250 DD (base 50°F) after sustained trap catch. But the timing depends on insecticide choice. Rimon (which is more ovicidal) should be applied at 75-100 DD 50°F after CM biofix; for Calypso, Assail, Delegate, Altacor, Belt, or Voliam Xpress or Voliam Flexi, 200-250 DD 50°F after biofix. An additional option is to apply a granulosis virus formulation at 200-250 DD 50°F. High moth pressure requires 2-3 sprays for the first generation, but in lower pressure orchards (with counts of less than 5 moths per trap per week), you can control CM with a single spray timed at 350 DD 50°F. Research in Washington and Michigan has shown that codling moth mating and egg laying activities take place primarily during a four-hour period, beginning around dusk, if temperatures are above 60°F during that period. Temperatures below 60°F impede male activity and prevent mating, so a cooler spring will delay significant egg hatch for the first generation. If weather data is available to predict this, it can be incorporated into the degree day model as egg hatch will occur 220 DD 50°F after the first flight when evening temperatures >60F. The first insecticide spray for OFM in peaches is recommended at 175 DD (base 45°F) after biofix (petal fall) and a second spray 10-14 days later, until trap counts subside; in apples, 1st generation OFM can be controlled with the petal fall spray. In summer, sprays for OFM in apples are applied 3-4 days after peak trap catch, or 7 days after the start of the 2nd flight.

Now just a few updates about upcoming events:

RMA Apple Insurance Listening Session:

June 27, 2023 : Goffstown, New Hampshire

10:00 a.m. to 12:00 p.m., Hillsborough County Extension Office (Large Conference Room)

329 Mast Rd., Goffstown, NH 03045

No RSVP required.

Details here: Summer 2023 Apple Grower Meetings | RMA (usda.gov)

Twilight Meetings:

The schedule is out for all of extension’s summer twilight meetings, and I wanted to highlight a few that may be of interest to the folks that tune into this call – the full list of Extensions event offerings this summer can be found on our website!

Tree Fruit meeting at Demeritt Hill Farm, July 15^th, 2023 5:30-7:30 pm

Tree Fruit Twilight Meeting at DeMerritt Farm | Extension (unh.edu)

Tree Fruit meeting at Apple Hill Farm, August 17^th, 2023 5:30-7:30 pm

Tree Fruit Twilight Meeting at Apple Hill Farm | Extension (unh.edu)

Blueberry IPM Twilight Meeting at Stark Farm, June 20^th, 2023

Blueberry IPM Twilight Meeting at Stark Farm | Extension (unh.edu)

All of the Production agriculture Twilight meetings:

2023 Production Agriculture Summer Twighlight Meeting | Extension (unh.edu)

Thank you for sticking around until the very end!  See you next week!

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Hi all!!  

 Welcome back to the NH Fruit Pest hotline, which is produced by staff members from the UNH Cooperative Extension Food and Agriculture team.   Today is May 23^rd , 2023.

While these recordings will highlight what you need to be looking for out in the field, I highly encourage you to find the transcripts online, as they will have more details and links about many of the pests, products, and models I’ll be describing in this call. Simply google “UNH Fruit IPM reports” to find them on our webpage. The transcript for this call may not be up until Wednesday afternoon.

In terms of growing degree days in Concord, NH we have accumulated 519 GDD in BE base 43F and 196 GDD in BE base 50F.

Lets dive into the frost event everyone has been talking about:

The frost event that occurred very late Wednesday, May 17^th and into the late morning hours of May 18^th caused extensive and quite variable damage across New Hampshire farms. Low temperatures reported ranged from 31F in Farmington to as low as 23F in Lebanon. While we had already lost our peach crop back on a single night in February, apples, pears, blueberries, strawberries and grapes were relatively undamaged until last week. While initial assessments are still underway, and damage varies considerably across locations and varieties, there was significant damage to apples, blueberries, and unprotected strawberries. We are not as certain about grapes and brambles at this point, but some potential damage is expected. Producers should document damage, contact their insurance providers and connect with their Extension specialists to evaluate and document damage, and develop appropriate IPM plans for the season based on the situation at their specific locations. Many questions are arising as to management decisions for the season ahead. Included below are a few resources as a start that may be helpful for some crops:

Apple Thinning Recommendations After the Frost: A Case-by-Case Scenario – Wisconsin Fruit

After the Freeze 2020 | Purdue University Facts for Fancy Fruit

Disease management after bad frost events? – Virginia Grape Disease Updates (grapepathology.org)

Strawberry Disease Management | Purdue University Facts for Fancy Fruit

Jumping into the plant pathogen updates:

Apple scab:

 50% Macintosh green tip date was established on 4/12 in Concord. This is the biofix to start the apple scab model in NEWA. Enter the date that this occurred in your orchards for the best accuracy from the model. The rains last week triggered a large ascospore release with 85% mature and ready to go prior to the rain event. Dry weather leading up to that point allowed for the accumulation of ascospores that were just waiting for moisture to be released. This is the time to use your more effective systemic materials along with a multisite such as Captan or Mancozeb. FRAC group 7 fungicides are preferred during this time of peak scab activity. Details on rotational options with other FRAC groups can be found here: https://extension.psu.edu/2023-disease-update-scab-and-fire-blight-infections-forecasted-for-the-weekend. We are now nearing the end of the primary scab season, with approximately 94% of ascospores mature as we head into a predicted infection event on Wednesday May 24th. Once this event has passed, maintain protection for approximately two weeks to ensure the last of the ascospores are controlled.

Consider some of the single site fungicides with the ability to translocate within leaf tissue for added control and some ability to kill very recent infections. An excellent description of the factors to consider for best fungicide selection can be found here: https://netreefruit.org/apples/diseases/apple-scab

Marssonina (Apple Blotch):

While we are currently in the tail end of primary apple scab season, you should remember that this fungus is also a concern and can be controlled with many of the same fungicides that control apple scab. The period of main concern is really at the tail end of apple scab season, but be aware and read up here about when and how to best control it. Keep an eye on any brown lesions beginning to form on your leaves – could be apple scab, could be marssonina!  Apple scab resistant  varieties tend to be the most susceptible to marssonina.

Fire Blight:

Much of the state is past bloom with apples and pears ranging from late bloom to fruit set depending on location and variety. We had infection events on May 11,12 and 13. Many growers elected to make a streptomycin application during that timeframe. Temperatures have been too cool beyond that event to worry much about infection. With warm temperatures predicted next week, any open flowers should be protected. Check the NEWA models for infection risk in relation to the crop development stage at your orchard. The take home message is that blossoms that have opened since your last application need to be covered with your material of choice. Continue to watch the weather forecast and cross-reference NEWA to best time applications.

Important: Any open blossoms still on trees should be considered vulnerable to infection from fireblight. Jeremy Delisle spoke with Penn State Tree Fruit Pathologist, Kari Peter on 5/22/23, and she explained that the nectaries on remaining flower blossoms are still open and present a potential infection pathway for fireblight. Continue to watch NEWA models until petal fall is complete and protect flowers as usual based on predicted risk and infection events.

Fire Blight | New England Tree Fruit Management Guide (netreefruit.org)

Powdery mildew:

Dry periods during scab season can be a prime time for infection by powdery mildew. Group 3 fungicides used for scab control will also control PM. Consider saving the group 11 fungicides until petal fall for control of summer diseases. Sulfur is also a good choice for PM control in conventional and organic orchards.

Powdery Mildew | New England Tree Fruit Management Guide (netreefruit.org)

Insects:

Plum curculio:

Control typically begins at petal fall with a whole block spray, followed by 1 or 2 perimeter row sprays depending on the weather and progression of this insect through its’ life cycle. Egg laying typically stops around 308 degree days after petal fall, at which time the need for targeted control generally stops. With this season progressing slowly so far with these cool temperatures, we are gaining degree days slowly. This means that the egg laying period for PC may be extended unless the temperatures drastically warm up.  Some southern NH orchards already have fruit at a susceptible stage for PC damage, as the insect prefers fruit at the 3-5 mm size for egg laying. Temperatures this week will certainly be warm enough for PC activity, so blocks of trees that are past petal fall should be protected. While few egg laying scars have been found while scouting orchards, Plum curculio will certainly be active this week.

Plum curculio (PC) | New England Tree Fruit Management Guide (netreefruit.org)

Codling moth:

In Concord we have yet to establish the biofix to start the codling moth model within NEWA. Southern NH has established the biofix from sustained trap captures of codling moth as of 5/22/23. Southern growers without traps on their farms could enter this date to start the degree day clock running for egg hatch by this pest, which is expected at 220 –250 DD at 50F from sustained catch.

Traps should be up and monitored daily in order to best track the development of this insect. Once sustained trap captures have been observed, enter the biofix date for your farm into the NEWA model to track development of the pest as egg laying approaches.

Codling moth (CM) | New England Tree Fruit Management Guide (netreefruit.org)

Interested in more details on how degree days are used to inform codling moth management practices?

Cornell has a wonderful fact sheet that talks about this, check out the quick summary below or check out the entire resource at this link: doc_72.pdf (cornell.edu)

Time insecticide applications based on trap data and degree day (DD) models for egg hatch. Spray timing for these pests is directed at newly hatched larvae, since most insecticides are not effective at controlling adults. There is a lag period for egg hatch after the moths fly. The first spray for CM is recommended at first egg hatch, which occurs 220-250 DD (base 50°F) after sustained trap catch. But the timing depends on insecticide choice. Rimon (which is more ovicidal) should be applied at 75-100 DD 50°F after CM biofix; for Calypso, Assail, Delegate, Altacor, Belt, or Voliam Xpress or Voliam Flexi, 200-250 DD 50°F after biofix. An additional option is to apply a granulosis virus formulation at 200-250 DD 50°F. High moth pressure requires 2-3 sprays for the first generation, but in lower pressure orchards (with counts of less than 5 moths per trap per week), you can control CM with a single spray timed at 350 DD 50°F. Research in Washington and Michigan has shown that codling moth mating and egg laying activities take place primarily during a four-hour period, beginning around dusk, if temperatures are above 60°F during that period. Temperatures below 60°F impede male activity and prevent mating, so a cooler spring will delay significant egg hatch for the first generation. If weather data is available to predict this, it can be incorporated into the degree day model as egg hatch will occur 220 DD 50°F after the first flight when evening temperatures >60F. The first insecticide spray for OFM in peaches is recommended at 175 DD (base 45°F) after biofix (petal fall) and a second spray 10-14 days later, until trap counts subside; in apples, 1st generation OFM can be controlled with the petal fall spray. In summer, sprays for OFM in apples are applied 3-4 days after peak trap catch, or 7 days after the start of the 2nd flight.

Thinning

After the frost event on 5/18/23, most growers are holding off on thinning for now. We are at an interesting spot, still assessing fruit damage, while still waiting to see how much of the apple crops will survive and remain on the trees to be considered “set”. More information is expected this week. UNH Extension has been in communication with Dr. Duane Green of UMass, and anticipate recommendations and considerations given the conditions experienced in New Hampshire and New England this spring.

The opportunity to thin potential fruit load begins at bloom and lasts until 3-4 weeks post petal fall. Consider using the Carbohydrate Thinning Model in NEWA to help make the best thinning management decisions based on factors such as localized weather patterns and other site-specific factors. This UMass resource outlines the best options and key considerations for chemical thinning: Fruit: HRT-Thinning Apples Chemically | Center for Agriculture, Food, and the Environment at UMass Amherst

RMA Apple Insurance Listening Session:

June 27, 2023 : Goffstown, New Hampshire

10:00 a.m. to 12:00 p.m., Hillsborough County Extension Office (Large Conference Room)

329 Mast Rd., Goffstown, NH 03045

No RSVP required.

Details here: Summer 2023 Apple Grower Meetings | RMA (usda.gov)

Twilight Meetings:

The schedule is out for all of extension’s summer twilight meetings, and I wanted to highlight a few that may be of interest to the folks that tune into this call – the full list of Extensions event offerings this summer can be found on our website!

Tree Fruit meeting at Demeritt Hill Farm, July 15^th, 2023 5:30-7:30 pm

Tree Fruit Twilight Meeting at DeMerritt Farm | Extension (unh.edu)

Tree Fruit meeting at Apple Hill Farm, August 17^th, 2023 5:30-7:30 pm

Tree Fruit Twilight Meeting at Apple Hill Farm | Extension (unh.edu)

All of the Production agriculture Twilight meetings:

2023 Production Agriculture Summer Twighlight Meeting | Extension (unh.edu)

Thank you for sticking around until the very end!  See you next week!

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Fruit Pest Hotline IPM Report 6/6/23

Hi all!!  

 Welcome back to the NH Fruit Pest hotline, which is produced by staff members from the UNH Cooperative Extension Food and Agriculture team.   Today is June 6^th , 2023.

While these recordings will highlight what you need to be looking for out in the field, I highly encourage you to find the transcripts online, as they will have more details and links about many of the pests, products, and models I’ll be describing in this call. Simply google “UNH Fruit IPM reports” to find them on our webpage. The transcript for this call may not be up until Wednesday afternoon.

In terms of growing degree days in Concord, NH we have accumulated 758 GDD in BE base 43F and 334 GDD in BE base 50F.

Recommendations for frost-damaged orchards and small fruit crops will be gone over at the end of this call.  Similar information can be found in last week’s report!

Jumping into the plant pathogen updates:

Apple scab:

The rains this week should certainly promote the last of the unreleased ascospores to be released.  Maintain protection and continue to scout over the next couple of weeks. Hopefully your orchard is clean of scab and this will mean the end of required control measures for the growing season. While visiting orchards over the past week, I have seen some primary scab infections present on leaves. Now is the time to remain diligent and maintain fungicide coverage over the next two weeks with the goal of wiping out these initial infections and putting an end to the need for control through the remainder of the season due to secondary infections.

An excellent description of the factors to consider for best fungicide selection can be found here: https://netreefruit.org/apples/diseases/apple-scab

Figure 1: Apple scab infection on upper (left photo) and lower (right photo) leaf surface. Credit: Jeremy DeLisle, UNH Extension

Marssonina (Apple Blotch):

While we are currently in the tail end of primary apple scab season, you should remember that this fungus is also a concern and can be controlled with many of the same fungicides that control apple scab. The period of main concern is really at the tail end of apple scab season, but be aware and read up here about when and how to best control it. Keep an eye on any brown lesions beginning to form on your leaves – could be apple scab, could be marssonina!  Apple scab resistant  varieties tend to be the most susceptible to marssonina.

Fire Blight:

Important: Any open blossoms still on trees should be considered vulnerable to infection from fire blight.  At this point we are mainly just seeing open blossoms on newly planted trees from the nursery. These blossoms should have been removed prior to opening to prevent the risk of infection, especially since we don’t want the trees putting energy towards fruit production as this early age. Rather, we want them focused on vegetative growth to fill their allotted space in the orchard. Choose a cool dry day to remove blossoms when risk of infection is lowest.

Consult the NEWA fireblight model to assess risk levels. Consider an application of copper to reduce bacteria in the surface of the tree prior to blossom removal. Clean pruning shears between trees to minimize risk of spreading bacteria from one tree to the next. 

Continue to scout orchards for shoot blight, including rootstock sucker infections. Prune and remove infected shoots 12 inches below the infected margin during cool, dry weather.

Pruning is particularly useful when blossom blight is well controlled and canker blight infections are thus the main source of inoculum for disease spread during the summer. Pruning can help limit disease spread but will be most effective if practiced rigorously during the first few weeks after bloom; pruning will do little to slow disease spread if delayed until a large number of infections are visible.

Routine use of antibiotics to prevent shoot blight spread during the summer is not effective or recommended. However, applications to protect new wounds immediately following a hailstorm can be very beneficial. With a cool and fairly dry bloom period, some growers made in through the prime infection period with just a couple of streptomycin applications. Keep in mind that saving at least one or the four allotted strep sprays in case of hail or damaging wind events is a good insurance strategy.

Fire Blight | New England Tree Fruit Management Guide (netreefruit.org)

Powdery mildew:

Keep an eye out for any infections in the next few weeks.

Powdery Mildew | New England Tree Fruit Management Guide (netreefruit.org)

Insects:

Plum curculio:          

In Concord the petal fall date we are using is 5/19/23. From that date, we have accumulated 195 degree days base 50F, and are predicted to have accumulated 238 DD by Sunday, June 11^th. This cool weather this week has us accumulating degree days very slowly. Hearing reports from New York and Pennsylvania, I suppose we should be thankful we are not dealing with the heat they currently are.  Egg laying typically stops around 308 degree days after petal fall, at which time the need for targeted control generally stops. With this season progressing slowly so far with these cool temperatures, we are gaining degree days slowly. It looks like we will be nearing the end of oviposition by the end of next week, at which point, we will be able to consider PC control for the season done.  For this week into next, continue to monitor growing degree days from petal fall using the PC model within NEWA to know when we are approaching the end of oviposition and the need for control.

An observation from the field is that in some orchards with very few viable fruits remaining on the trees after the frost, PC seems to be laying high numbers of eggs in those fruits. This is the behavior that we anticipated. It seems targeted perimeter application of insecticides targeting PC adults at this point in the season is still warranted as we think about reducing this population of insects for next season. 

Plum curculio (PC) | New England Tree Fruit Management Guide (netreefruit.org)

Figure 2: Plum Cucurlio damage to Honeycrisp fruitlet, 6/2/23, Photo credit: Jeremy DeLisle, UNH Extension

Codling moth:

Codling moth –In Canterbury, we established the biofix date of 5/26/23 to start the codling moth model within NEWA and have reduced the frequency of trap checking for this insect to once a week. Southern NH established the biofix of codling moth as of 5/22/23. Southern growers without traps on their farms could enter this date to start the degree day clock running for egg hatch by this pest.  If you do you’re your own traps, once sustained trap captures have been observed, enter the biofix date for your farm into the NEWA model to track development of the pest. For most orchards in NH, codling moth flight is well underway and egg laying is currently happening. 

Today we have accumulated 138 DD base 50F from our biofix and predict we will have reached 181 DD by June 11^th.

We will likely have reached the beginning of egg hatch by late next week, at which time the emerging larvae are most susceptible to control using many of the recommended insecticides. NEWA data predicts that the required 220 DD will be reached by Sunday, June 11^th, beginning the period of egg hatch for the first generation of codling moth.

Codling moth (CM) | New England Tree Fruit Management Guide (netreefruit.org)

Interested in more details on how degree days are used to inform codling moth management practices?

Cornell has a wonderful fact sheet that talks about this, check out the entire resource at this link: doc_72.pdf (cornell.edu)

Figure 3: Codling moth trap captures showing sticky trap bottom insert along with pheromone lure, Photo credit: Jeremy DeLisle, UNH Extension

Figure 4: Close up of a codling moth from the sticky trap, Photo credit: Jeremy DeLisle

Figure 5: Codling moth trap captures for Merrimack County (Credit to Jeremy DeLisle)

Oriental Fruit Moth:

Keep an eye out for them, we are seeing more of them in traps captured in Merrimack County.

Figure 6: Oriental Fruit Moth (OFM) trap captures for Merrimack County

A few updates about upcoming events:

RMA Apple Insurance Listening Session:

June 27, 2023 : Goffstown, New Hampshire

10:00 a.m. to 12:00 p.m., Hillsborough County Extension Office (Large Conference Room)

329 Mast Rd., Goffstown, NH 03045

No RSVP required.

Details here: Summer 2023 Apple Grower Meetings | RMA (usda.gov)

Twilight Meetings:

The schedule is out for all of extension’s summer twilight meetings, and I wanted to highlight a few that may be of interest to the folks that tune into this call – the full list of Extensions event offerings this summer can be found on our website!

Tree Fruit meeting at Demeritt Hill Farm, July 15^th, 2023 5:30-7:30 pm

Tree Fruit Twilight Meeting at DeMerritt Farm | Extension (unh.edu)

Tree Fruit meeting at Apple Hill Farm, August 17^th, 2023 5:30-7:30 pm

Tree Fruit Twilight Meeting at Apple Hill Farm | Extension (unh.edu)

Blueberry IPM Twilight Meeting at Stark Farm, June 20^th, 2023

Blueberry IPM Twilight Meeting at Stark Farm | Extension (unh.edu)

All of the Production Agriculture Twilight meetings:

2023 Production Agriculture Summer Twighlight Meeting | Extension (unh.edu)

Lets dive into the frost event everyone has been talking about:

While you all have probably done this already, producers should document damage, contact their insurance providers, and connect with their Extension specialists to evaluate and document damage, and develop appropriate IPM plans for the season based on the situation at their specific locations.

Many questions are arising as to management decisions for the season ahead considering the damage to fruiting crops throughout New Hampshire. Included below are a few suggestions as a start that may be helpful for some crops:

I’ll jump into frost damage control/considerations first: *This is a repeat from the last report, but still valuable!

Managing berry planting after frost: (*Northeast Berry Call Recommendations – thanks to all the folks offering advice to the region!)

Pest control:

Plantings with total fruit loss still need to be actively managed for pests and weeds. Potential for botrytis is greater in all affected berries with dead tissue on the plant (black strawberry blossoms, blighted tips of blueberry canes, black bramble flowers). It would be a good idea to spray now for botrytis, especially in strawberries. Other fungal pathogens don’t live in dead tissue as botrytis does, so we only worry about botrytis.

Diseases | Center for Agriculture, Food, and the Environment (umass.edu)

Diseases | Center for Agriculture, Food, and the Environment (umass.edu)

Diseases | Center for Agriculture, Food, and the Environment (umass.edu)

Pruning:

In bush and cane-berries that have a big percentage of crop lost, anticipate summer thinning because extra energy will be allocated to vegetative growth. Perhaps due to the lost crop this year, next year’s crop will be larger.

June-bearing strawberry plantings should not be renovated now if they had total crop loss. They should be renovated in July or August as usual. Additional Nitrogen applications may be helpful in the case of total crop loss by helping the plants put on biomass. Crowns should be cut in half and checked for damage from frost. Depending on the degree of damage there, may have diminishing returns on inputs.

Watering:

Plantings should be watered to minimize drought stress. This might help remaining fruit recover instead of senescing.

Fertility:

 At this point in the season most blueberries have had 1 round of fertilizer applied already. A second round of fertilizer at this point in the season is important because it helps set the fruiting buds. Foliar nutrient sprays are popular amongst growers. Some have seen good results from Megafol (3-0-8). Some growers do 2 applications at a pint/acre each (mid-April and post-bloom), while others do 1 big application at 1 quart/acre each. Some growers also spray potassium on blossoms and developing fruit for winter protection. This is especially done in apples, sometimes on raspberries too. The K+ (potassium) ions prevent the growth of ice-nucleating bacteria; copper sprays work too.

Managing tree fruit after frost (Advice from Terence Bradshaw, UVM Extension)

This is just a quick recap, please check out his full post: VT Apple IPM: Management in light of a difficult crop situation – UVM Fruit Blog

Thinning:

·      For orchards that have no fruit or heavily damaged fruits (+ 75% ) do not consider thinning this year.

·      For orchards with less than 20%, consider thinning as normal this year.

·      For orchards that have moderate damage between 25 and 75%, the answer is a bit more site-specific. Not thinning those orchards may result in heavy set of small fruit that could promote biennialism, but trees are likely to respond well to thinners applied in the next week, given both the cold damage and the warm sunny, weather that we are expecting coming up.

·      At the UVM Orchard, which experienced moderate fruit damage between 20 and 70%, depending upon cultivar, they decided to apply a low rate of NAA thinner with a low rate of carbaryl insecticide. They have 70 varieties across the whole orchard, and it is difficult to thin based upon variety even in a ‘normal’ year, which is not too different from what many other retail orchards might be dealing with.  It is difficult to provide blanket recommendations to growers given the state of the crop this year.

·      In the end, Dr. Bradshaw recommends trusting your gut – if you have a good crop thin it, if you have a moderate crop consider thinning it lightly as you could always come back in later next week and be better able to visualize the effects of both the frost and any thinner applications you may have applied.

Full post: VT Apple IPM: Management in light of a difficult crop situation – UVM Fruit Blog

More on thinning:

The opportunity to thin potential fruit load begins at bloom and lasts until 3-4 weeks post petal fall. Consider using the Carbohydrate Thinning Model in NEWA to help make the best thinning management decisions based on factors such as localized weather patterns and other site-specific factors. This UMass resource outlines the best options and key considerations for chemical thinning: Fruit: HRT-Thinning Apples Chemically | Center for Agriculture, Food, and the Environment at UMass Amherst

Insect management:  (Advice from Terence Bradshaw, UVM Extension)

This is just a quick recap, please check out his full post: VT Apple IPM: Management in light of a difficult crop situation – UVM Fruit Blog

·      This will differ depending upon the state of the crop in your orchard.

·      For orchards with a full or even a moderate crop, plan to manage your insect pests as normal this year. Petal fall insecticide sprays should have already gone on in most orchards.

·      Normally petal fall sprays are targeted at European apple sawfly, early emerging codling moth, and plum curculio. All of those pests are fruit feeders so orchards that have no fruit or are assumed to have very little fruit may consider omitting all insecticide applications targeted toward protecting fruit.

·      The difficult situation comes where orchards have a low set of fruit where the expense of the application on a per bushel basis could be quite high but the value of the few apples you have is also high. If there's any question about whether or not you have sufficient crop set in your orchard, it is recommended to go ahead and treat as usual. If you have no crop or nearly no crop, then you may consider omitting those insecticides.

·      However, it is worth it to consider maintaining some coverage primarily for shoot and leaf feeding, lepidopterous caterpillar larvae. That may mean including BT sprays in petal fall, scab, thinning, or other sprays in order to keep down leps like the obliquebanded leaf roller and tent caterpillar.

·      In orchards with little to no crop, the great reduction insecticides used this year may allow beneficial populations to increase substantially, setting you up for a better IPM program next year.

·      It is not recommended to ignore trunk applications of Assail or another appropriate insecticide in young plantings to avoid issues with dogwood and other borers.

Full post: VT Apple IPM: Management in light of a difficult crop situation – UVM Fruit Blog

Nutrients:  :  (Advice from Terence Bradshaw, UVM Extension)

This is just a quick recap, please check out his full post: VT Apple IPM: Management in light of a difficult crop situation – UVM Fruit Blog

·      For trees with normal or moderate crop load, fertilize as you normally would.

·      For trees with little to no crop nitrogen applications should not go on this year unless trees are under-vigorous.

·      For trees with little to no crop this year potassium is not likely to be removed in any significant amount because that is usually removed in harvested fruit. However, it is important to maintain or improve the potassium status in your orchards to ensure that you have an appropriate amount of that nutrient going into next year when it is likely that orchards will have a heavy crop load.

·      He does recommend thinking about applying magnesium potassium fertilizers in the next month or so regardless of crop status.

Thank you for sticking around until the very end!  See you next week!

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Fruit Pest Hotline IPM Report 6/13/23

Hi all!!  

 Welcome back to the NH Fruit Pest hotline, which is produced by staff members from the UNH Cooperative Extension Food and Agriculture team.   Today is June 13^th , 2023.

While these recordings will highlight what you need to be looking for out in the field, I highly encourage you to find the transcripts online, as they will have more details and links about many of the pests, products, and models I’ll be describing in this call. Simply google “UNH Fruit IPM reports” to find them on our webpage. The transcript for this call may not be up until Wednesday afternoon.

In terms of growing degree days in Concord, NH we have accumulated 875 GDD in BE base 43F and 403 GDD in BE base 50F.

Before we get into the pathogens:

Many questions are arising as to management decisions for the season ahead considering the frost damage to fruiting crops throughout New Hampshire.

You can access the suggestions from UNH Extension Staff and Terry Bradshaw up at UVM in previous IPM reports (6/6/23) or here: May 2023 – UVM Fruit Blog

Moving on to the disease updates:

Apple scab:

The rains this week should certainly promote the last of the ascospores to be released.  Maintain protection and continue to scout over the next couple of weeks. Hopefully your orchard is clean of scab and this will mean the end of required control measures for the growing season. While visiting orchards over the past week, Jeremy Delisle spotted some primary scab infections present on leaves. Now is the time to remain diligent and maintain fungicide coverage over the next two weeks with the goal of wiping out these initial infections and putting an end to the need for control through the remainder of the season due to secondary infections.

An excellent description of the factors to consider for best fungicide selection can be found here: https://netreefruit.org/apples/diseases/apple-scab

Figure 1: Apple scab infection on upper and lower leaf surface, Photo, Jeremy DeLisle, UNH Extension

Marssonina (Apple Blotch):

While we are currently at the very end of primary apple scab season, you should remember that this fungus is also a concern and can be controlled with many of the same fungicides that control apple scab. The period of primary concern is really at the tail end of apple scab season, read up more about it here: Apple Disease - Marssonina Blotch (psu.edu).

Fire Blight:

Continue to scout orchards for shoot blight, including rootstock sucker infections. Prune and remove infected shoots at least 12-18 inches below the infected margin during cool, dry weather.

Pruning is particularly useful when blossom blight is well controlled and canker blight infections are thus the main source of inoculum for disease spread during the summer. Pruning can help limit disease spread, but will be most effective if practiced rigorously during the first few weeks after bloom; pruning will do little to slow disease spread if delayed until a large number of infections are visible.

Routine use of antibiotics to prevent shoot blight spread during the summer is not effective or recommended. However, applications to protect new wounds immediately following a hailstorm can be very beneficial. With a cool and fairly dry bloom period, some growers made in through the prime infection period with just a couple of streptomycin applications. Keep in mind that saving at least one or the four allotted strep sprays in case of hail or damaging wind events is a good insurance strategy.

In her most recent report, Kathleen Leahy reminds us of an article from Good Fruit Grower highlighting recent research comparing cutting and sanitization strategies to find the best removal methods for fire blight strikes. It’s definitely worth the read:

Good to Know: Take a bite out of blight - Good Fruit Grower

Fire Blight | New England Tree Fruit Management Guide (netreefruit.org)

Moving onto the insect pests:

Plum curculio:

Plum curculio activity is beginning to decline and any curculio remaining in trees will usually not move to other locations.

Plum curculio only need to be controlled until 308 DD have accumulated after petal fall. Make sure that the predicted residual coverage (10-14 days) from the last spray will protect fruit until DD accumulation reaches this value.

In Concord the petal fall date we are using is 5/19/23. From that date, we have accumulated 263 degree days base 50F, and are predicted to have accumulated 307 DD by Friday, June 16^th. Egg laying typically stops around 308 degree days after petal fall, at which time the need for targeted control generally stops. With this season progressing slowly so far with these cool temperatures, we are gaining degree days slowly. It looks like we will be nearing the end of oviposition by the end of this week, at which point, we will be able to consider PC control for the season done.  

For this week into next, continue to monitor growing degree days from petal fall using the PC model within NEWA to know when we are approaching the end of oviposition and the need for control. Northern orchards are slightly behind in degree day accumulations, so oviposition will be extended into next week. An observation from the field is that in some orchards with very few viable fruits remaining on the trees after the frost, PC seems to be laying high numbers of eggs in those fruits. This is the behavior that we anticipated. It seems targeted perimeter application of insecticides targeting PC adults at this point in the season is still warranted as we think about reducing this population of insects for next season.  

Remember, if you have applied an effective insecticide with residual activity still present on the trees, that application may take you through the end of oviposition depending on the date of application and the material used.

Plum curculio (PC) | New England Tree Fruit Management Guide (netreefruit.org)

 Codling moth:

In Canterbury, we established the biofix date of 5/26/23 to start the codling moth model within NEWA and have reduced the frequency of trap checking for this insect to once a week. Once sustained trap captures have been observed, enter the biofix date for your farm into the NEWA model to track development of the pest. Southern NH established the biofix of codling moth as of 5/22/23. Southern growers without traps on their farms could enter this date to start the degree day clock running for egg hatch by this pest. NEWA data predicts that the required 220 DD was reached on Sunday, June 11^th, and in most orchards in NH, codling moth flight is well underway and egg laying is currently happening.  Today we have accumulated 206 DD base 50F from our biofix and predict we will have reached 250 DD by June 16^th, these DD calculations mark the prime window of egg hatch, and the most effective time for controlling the emerging larvae with many of the recommended insecticides.

The take home message: Now, or later this week, is the time to be targeting those emerging codling moth larvae.

Codling moth (CM) | New England Tree Fruit Management Guide (netreefruit.org)

Figure 2: Codling moth trap captures for Merrimack County

Want to learn more about DD calculations and how they relate to the codling moth control  recommendations?

Full resource available here: doc_72.pdf (cornell.edu) , see below for the shorter version!

Time insecticide applications based on trap data and degree day (DD) models for egg hatch. Spray timing for these pests is directed at newly hatched larvae, since most insecticides are not effective at controlling adults. There is a lag period for egg hatch after the moths fly. The first spray for CM is recommended at first egg hatch, which occurs 220-250 DD (base 50°F) after sustained trap catch. Timing depends on insecticide choice. Calypso, Assail, Delegate, Altacor, Belt, or Voliam Xpress or Voliam Flexi are most effective when applied at 200-250 DD 50°F after biofix. An additional option is to apply a granulosis virus formulation at 200-250 DD 50°F. High moth pressure requires 2-3 sprays for the first generation, but in lower pressure orchards (with counts of less than 5 moths per trap per week), you can control CM with a single spray timed at 350 DD 50°F.

In apples, 1st generation OFM can be controlled with the petal fall spray. In summer, sprays for OFM in apples are applied 3-4 days after peak trap catch, or 7 days after the start of the 2nd flight.

 Oriental Fruit moth:

Be on the lookout, trap captures are increasing in Merrimac county!

Oriental Fruit Moth (OFM) | New England Tree Fruit Management Guide (netreefruit.org)

Figure 3: OFM trap captures for Merrimack County

San Jose Scale

First generation crawlers are produced beneath female scale covers during this period. If monitoring for crawlers, double-sided sticky tape traps should be placed around tree limbs at this time.

San Jose scale (SJS) | New England Tree Fruit Management Guide (netreefruit.org)

Something a little different, but still very good to know:

Monitoring Spotted Wing Drosophila (SWD) with Traps

*recently updated by Anna Wallingford, Assistant State Specialist, Associate Research Professor and excellent entomologist*

Note:  No SWD caught in UNH traps as of today, 6/14/2023

Spotted wing drosophila (SWD) attacks ripening and ripe raspberries, blackberries, blueberries, grapes, cranberries, late cherries, fall strawberries, plums and peaches, plus fruit of many wild hosts. If you wish to protect your fruit from becoming infested, it is critical to set up traps for the insects, and to monitor those traps weekly when you have ripening crop present. The first flies will probably be trapped between July 2 and 12, and numbers will peak in September or October.

These traps ARE NOT TO CONTROL the flies! Once you detect flies, the crop should be protected with insecticides. Most of the good insecticides should give about seven days of protection, but can be washed off by rain. After you spray, set out fresh traps to determine when crops become at risk again.

 Commercial vs. Home-Made Traps

When SWD first appeared in NH, the commercial traps that existed were not effective in comparison with home-made traps. However, effective commercial traps and baits are now available from both Scentry and Trécé, that are hung in jar traps full of soapy water as drowning solution. More recently, Trécé has marketed their lure with red sticky traps as a “dry trap” alternative to traps with water drowning solutions. All trapping types have their own pros and cons in terms of logistics of use but all are excellent at determining presence or absence of flies in susceptible crops.

In our UNH Cooperative Extension monitoring program, we are now using Trécé traps and lures for SWD. These traps are reusable, and are available from standard suppliers of IPM products (e.g. Great Lakes IPM).

When to set up the traps? Do this as soon as fruit starts to ripen. Fruits that ripen before July 1 are not likely to be at risk. You can stop monitoring when harvest of susceptible crops is over for you.

Where to set the traps? Set the traps IN the crop, in the shade, AMONG THE FOLIAGE near fruit. We recommend checking traps every 5-6 days at first, moving to every 3-5 days in August (hot weather). As the weather cools, you can lengthen the check interval. Keep checking as long as you have ripe fruit to protect.

Which crops need protection? The most susceptible crops seem to be raspberries, blueberries and strawberries that ripen in August-September; thin-skinned, dark-colored grapes; and some peaches and plums (especially white-fleshed peaches). We don’t know how heavily currants and cranberries are attacked.

How many traps do I need?  For most plantings, three well-placed traps should be enough and you should base management actions on an average of the number of flies you trap in each block. If you have different crops, you’ll want traps in each crop, because the pattern of attack varies crop-to-crop. If you have different varieties of the same crop, begin monitoring in the first variety to ripen, and move the traps to others with ripe fruit when harvest wanes on that first variety. If your crop is in several blocks that are managed (e.g. sprayed) separately, you will need traps in each block.

How do I check the traps?  Check traps at least once per week. To check the trap, remove the lid, and pour the liquid bait into a shallow white pan or saucer. In bright light, look for the male flies (they are about 2mm long, with light tan body, red/orange eyes, and have a dot near the tip of each wing) with a 2X magnifying glass. When done counting the male SWD’s, write the number down. If you find male flies, your crop is at risk. If your threshold for risk is a little higher, you can wait until you find an average of 5 male SWD in all three traps. Find this example of a sliding scale of risk for SWD infestation in wild blueberry https://extension.umaine.edu/blueberries/factsheets/insects/210-spotted-wing-drosophila/

Making Your Own Traps

From 2012-2016, we and many colleagues across the Northeast set out hundreds of traps, and learned what combinations worked well enough to make trapping a useful tool. Most of these baits relied on odors from fermentation to attract flies, including apple cider vinegar, wine, grape juice, yeasts, sugars, bread doughs, etc. Many of these bait recipes are messy, smell, and trap many non-target insects that make detection of SWD difficult. Poorly set or designed traps do not work well enough to predict when you need to protect crops. If you prefer to make your own traps rather than purchase traps, the following tips may help.

This trap design works well: We use red plastic 18 oz Solo cups with transparent lids. We placed a black band of electrician’s tape a bit below the rim. We used a heated nail to melt 1/8 inch holes in the cup, to allow the insects to get in, and the odor to escape. We don’t make those holes too large, or wasps will get in. We placed the entrance holes in and around that band, about 30 to 35 holes per trap. We leave one sector of the cup without holes, to make it easy to pour out and examine the liquid bait, without spilling any.

Add just a drop or two of liquid soap to the bait. Non-scented soap is preferable as flowery-scented soaps might decrease bait effectiveness. The soap decreases the surface tension of the bait, making it easier for the small flies to fall in and drown.

When we used the dough baits, the solid yeast/dough bait was placed inside a smaller 4-oz lidded cup within the larger 18-oz trap. We cut a hole (1-inch diameter) in the lid. Over the hole we placed fine insect netting, and fastened it with a hot glue gun. The netting is to allow the yeast odor out, but not let flies in. So the assembled trap is a large red cup. Inside that is 2 oz of liquid bait, and floating upright in the liquid bait is the smaller cup with the netted lid.

When check traps containing attractive baits, make sure to collect the old liquid bait in a waste container, and add fresh bait to the trap. Don’t pour the old bait on the ground in your fruit planting, or it will compete with your traps for the flies’ attention.

Point of interest:

UNH Extension, USDA Natural Resources Conservation Service and the NH Conservation Districts have been partnering on a three-year demonstration project investigating the efficacy, ease of use, cost of installation and potential return on investments associated with installing SWD exclusion netting systems on three farms here in NH. Those partner farms are Bascom Road Blueberry Farm in Newport, Stark Farm in Dunbarton, and Heron Pond Farm in South Hampton. To date, the systems have been highly effective at excluding SWD flies, with zero trap captures reported to date, along with no loss due to infested fruit. To learn more about the types of systems being installed and the potential for new construction versus retrofitting existing bird netting structures, join us at our upcoming twilight meeting on June 20^th at Stark Farm. Details are available at the link at the bottom of this page.

Figure 4: SWD netting being installed for the second year in a row at Heron Pond Farm in South Hampton, NH. Photo by Jeremy DeLisle, Field Specialist, Food and Agriculture, UNH Extension

Upcoming meetings:

June 14^th, 2023

NH Veg and Berry Growers Association Twilight Meeting: New Farm Technology for Veg and Fruit Producers Field Day

June 15^th, 2023

Tree Fruit Twilight Meeting at DeMerritt Farm | Extension (unh.edu)

June 20^th, 2023

Blueberry IPM Twilight Meeting at Stark Farm | Extension (unh.edu)

RMA Apple Insurance Listening Session: June 27, 2023 : Goffstown, New Hampshire

10:00 a.m. to 12:00 p.m., Hillsborough County Extension Office (Large Conference Room)

329 Mast Rd., Goffstown, NH 03045

No RSVP Necessary!

Summer 2023 Apple Grower Meetings | RMA (usda.gov)

Thanks for sticking around until the end!  See you all next week!

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Fruit IPM Report 6/20/23

Hi all!!  

  Welcome back to the NH Fruit Pest hotline, which is produced by staff members from the UNH Cooperative Extension Food and Agriculture team.   Today is June 20^th , 2023.

 While these recordings will highlight what you need to be looking for out in the field, I highly encourage you to find the transcripts online, as they will have more details and links about many of the pests, products, and models I’ll be describing in this call. Simply google “UNH Fruit IPM reports” to find them on our webpage. The transcript for this call may not be up until Wednesday afternoon.

 In terms of growing degree days in Concord, NH we have accumulated 1020 GDD in BE base 43F and 499 GDD in BE base 50F.

 We are in a bit of a lull right now – so I  have a shorter update for all of you!

Jumping into the disease updates:

Apple scab:

While primary infection is over at this point, some orchards are still seeing scab on leaves and fruitlets.

An excellent description of the factors to consider for best fungicide selection can be found here: https://netreefruit.org/apples/diseases/apple-scab

Figure 1: Apple scab infection on upper and lower leaf surface, Photo, Jeremy DeLisle, UNH Extension

Fire blight:

Continue to scout orchards for shoot blight, including rootstock sucker infections. Prune and remove infected shoots at least 12-18 inches below the infected margin during cool, dry weather.

Pruning is particularly useful when blossom blight is well controlled and canker blight infections are thus the main source of inoculum for disease spread during the summer. Pruning can help limit disease spread, but will be most effective if practiced rigorously during the first few weeks after bloom; pruning will do little to slow disease spread if delayed until a large number of infections are visible.

Routine use of antibiotics to prevent shoot blight spread during the summer is not effective or recommended. However, applications to protect new wounds immediately following a hailstorm can be very beneficial. With a cool and fairly dry bloom period, some growers made in through the prime infection period with just a couple of streptomycin applications. Keep in mind that saving at least one or the four allotted strep sprays in case of hail or damaging wind events is a good insurance strategy.

In her most recent report, Kathleen Leahy reminds us of an article from Good Fruit Grower highlighting recent research comparing cutting and sanitization strategies to find the best removal methods for fire blight strikes. It’s definitely worth the read:

Good to Know: Take a bite out of blight - Good Fruit Grower

Moving onto the insect pests:

Plum curculio

Pest status: Plum curculio activity is beginning to decline and any curculio remaining in trees will usually not move to other locations.

Plum curculio only need to be controlled until 308 DD have accumulated after petal fall. Make sure that the predicted residual coverage (10-14 days) from the last spray will protect fruit until DD accumulation reaches this value.

In Concord the petal fall date we are using is 5/19/23. From that date, we have accumulated 388 degree days base 50F. Egg laying typically stops around 308 degree days after petal fall, at which time the need for targeted control generally stops. According to the models, we can consider PC control for the season done – in Concord.

For this week into next, continue to monitor growing degree days from petal fall using the PC model within NEWA to know when you are approaching the end of oviposition and the need for control. Northern orchards are slightly behind in degree day accumulations, so oviposition might be extended a bit longer, but you should be there soon.

 An observation from the field is that in some orchards with very few viable fruits remaining on the trees after the frost, PC seems to be laying high numbers of eggs in those fruits. This is the behavior that we anticipated. It seems targeted perimeter application of insecticides targeting PC adults at this point in the season is still warranted as we think about reducing this population of insects for next season.  

Remember, if you have applied an effective insecticide with residual activity still present on the trees, that application may take you through the end of oviposition depending on the date of application and the material used.

Codling moth:

In Canterbury, we established the biofix date of 5/26/23 to start the codling moth model within NEWA and have reduced the frequency of trap checking for this insect to once a week. Once sustained trap captures have been observed, enter the biofix date for your farm into the NEWA model to track development of the pest. For most orchards in NH, codling moth flight is well underway and egg laying is currently happening.  

Today we have accumulated 303 DD base 50F from our biofix and reached 250 DD by June 16^th, marking the prime window of egg hatch and the most effective time for controlling the emerging larvae using many of the recommended insecticides.

We are still seeing high trap captures for the first generation of codling moth in Merrimac county (see Figure 2). This means that egg laying is still occurring, and controls will need to be applied for an extended time period. Southern NH established the biofix of codling moth as of 5/22/23. Southern growers without traps on their farms could enter this date to start the degree day clock running for egg hatch by this pest.

Trapping in the orchard is the best way to know what is happening with populations of insects in your specific location. Consider adding a few traps to your orchard to better understand the dynamics of key insect pests from one season to the next.

 More information from Cornell about codling moth Degree Day calculations:

Time insecticide applications based on trap data and degree day (DD) models for egg hatch. Spray timing for these pests is directed at newly hatched larvae, since most insecticides are not effective at controlling adults. There is a lag period for egg hatch after the moths fly. The first spray for CM is recommended at first egg hatch, which occurs 220-250 DD (base 50°F) after sustained trap catch. Timing depends on insecticide choice. Calypso, Assail, Delegate, Altacor, Belt, or Voliam Xpress or Voliam Flexi are most effective when applied at 200-250 DD 50°F after biofix. An additional option is to apply a granulosis virus formulation at 200-250 DD 50°F. High moth pressure requires 2-3 sprays for the first generation, but in lower pressure orchards (with counts of less than 5 moths per trap per week), you can control CM with a single spray timed at 350 DD 50°F.

In apples, 1st generation OFM can be controlled with the petal fall spray. In summer, sprays for OFM in apples are applied 3-4 days after peak trap catch, or 7 days after the start of the 2nd flight. In peach orchards, look for flagging shoots from larval activity in tips of new shoots. Full resource available here: doc_72.pdf (cornell.edu)

Figure 2: Codling moth trap captures for Merrimack County

Figure 3: Oriental Fruit Moth (OFM) trap captures for Merrimack County

San Jose Scale:

First generation crawlers are produced beneath female scale covers during this period. If monitoring for crawlers, double-sided sticky tape traps should be placed around tree limbs at this time.

San Jose scale (SJS) | New England Tree Fruit Management Guide (netreefruit.org)

Monitoring Spotted Wing Drosophila (SWD) with Traps (recently updated by Anna Wallingford, Assistant State Specialist, Associate Research Professor and excellent entomologist)

Spotted wing drosophila (SWD) attacks ripening and ripe raspberries, blackberries, blueberries, grapes, cranberries, late cherries, fall strawberries, plums and peaches, plus fruit of many wild hosts. If you wish to protect your fruit from becoming infested, it is critical to set up traps for the insects, and to monitor those traps weekly when you have ripening crop present. The first flies will probably be trapped between July 2 and 12, and numbers will peak in September or October.

These traps ARE NOT TO CONTROL the flies! Once you detect flies, the crop should be protected with insecticides. Most of the good insecticides should give about seven days of protection, but can be washed off by rain. After you spray, set out fresh traps to determine when crops become at risk again.

Commercial vs. Home-Made Traps

When SWD first appeared in NH, the commercial traps that existed were not effective in comparison with home-made traps. However, effective commercial traps and baits are now available from both Scentry and Trécé, that are hung in jar traps full of soapy water as drowning solution. More recently, Trécé has marketed their lure with red sticky traps as a “dry trap” alternative to traps with water drowning solutions. All trapping types have their own pros and cons in terms of logistics of use but all are excellent at determining presence or absence of flies in susceptible crops.

In our UNH Cooperative Extension monitoring program, we are now using Trécé traps and lures for SWD. These traps are reusable, and are available from standard suppliers of IPM products (e.g. Great Lakes IPM).

When to set up the traps? Do this as soon as fruit starts to ripen. Fruits that ripen before July 1 are not likely to be at risk. You can stop monitoring when harvest of susceptible crops is over for you.

Where to set the traps? Set the traps IN the crop, in the shade, AMONG THE FOLIAGE near fruit. We recommend checking traps every 5-6 days at first, moving to every 3-5 days in August (hot weather). As the weather cools, you can lengthen the check interval. Keep checking as long as you have ripe fruit to protect.

Which crops need protection? The most susceptible crops seem to be raspberries, blueberries and strawberries that ripen in August-September; thin-skinned, dark-colored grapes; and some peaches and plums (especially white-fleshed peaches). We don’t know how heavily currants and cranberries are attacked.

How many traps do I need?  For most plantings, three well-placed traps should be enough and you should base management actions on an average of the number of flies you trap in each block. If you have different crops, you’ll want traps in each crop, because the pattern of attack varies crop-to-crop. If you have different varieties of the same crop, begin monitoring in the first variety to ripen, and move the traps to others with ripe fruit when harvest wanes on that first variety. If your crop is in several blocks that are managed (e.g. sprayed) separately, you will need traps in each block.

How do I check the traps?  Check traps at least once per week. To check the trap, remove the lid, and pour the liquid bait into a shallow white pan or saucer. In bright light, look for the male flies (they are about 2mm long, with light tan body, red/orange eyes, and have a dot near the tip of each wing) with a 2X magnifying glass. When done counting the male SWD’s, write the number down. If you find male flies, your crop is at risk. If your threshold for risk is a little higher, you can wait until you find an average of 5 male SWD in all three traps. Find this example of a sliding scale of risk for SWD infestation in wild blueberry https://extension.umaine.edu/blueberries/factsheets/insects/210-spotted-wing-drosophila/

Making Your Own Traps

From 2012-2016, we and many colleagues across the Northeast set out hundreds of traps, and learned what combinations worked well enough to make trapping a useful tool. Most of these baits relied on odors from fermentation to attract flies, including apple cider vinegar, wine, grape juice, yeasts, sugars, bread doughs, etc. Many of these bait recipes are messy, smell, and trap many non-target insects that make detection of SWD difficult. Poorly set or designed traps do not work well enough to predict when you need to protect crops. If you prefer to make your own traps rather than purchase traps, the following tips may help.

This trap design works well: We use red plastic 18 oz Solo cups with transparent lids. We placed a black band of electrician’s tape a bit below the rim. We used a heated nail to melt 1/8 inch holes in the cup, to allow the insects to get in, and the odor to escape. We don’t make those holes too large, or wasps will get in. We placed the entrance holes in and around that band, about 30 to 35 holes per trap. We leave one sector of the cup without holes, to make it easy to pour out and examine the liquid bait, without spilling any.

Add just a drop or two of liquid soap to the bait. Non-scented soap is preferable as flowery-scented soaps might decrease bait effectiveness. The soap decreases the surface tension of the bait, making it easier for the small flies to fall in and drown.

When we used the dough baits, the solid yeast/dough bait was placed inside a smaller 4-oz lidded cup within the larger 18-oz trap. We cut a hole (1-inch diameter) in the lid. Over the hole we placed fine insect netting, and fastened it with a hot glue gun. The netting is to allow the yeast odor out, but not let flies in. So the assembled trap is a large red cup. Inside that is 2 oz of liquid bait, and floating upright in the liquid bait is the smaller cup with the netted lid.

When check traps containing attractive baits, make sure to collect the old liquid bait in a waste container, and add fresh bait to the trap. Don’t pour the old bait on the ground in your fruit planting, or it will compete with your traps for the flies’ attention.

Point of interest:

UNH Extension, USDA Natural Resources Conservation Service and the NH Conservation Districts have been partnering on a three-year demonstration project investigating the efficacy, ease of use, cost of installation and potential return on investments associated with installing SWD exclusion netting systems on three farms here in NH. Those partner farms are Bascom Road Blueberry Farm in Newport, Stark Farm in Dunbarton, and Heron Pond Farm in South Hampton. To date, the systems have been highly effective at excluding SWD flies, with zero trap captures reported to date, along with no loss due to infested fruit. To learn more about the types of systems being installed and the potential for new construction versus retrofitting existing bird netting structures, join us at our upcoming twilight meeting on June 20^th at Stark Farm. Details are available at the link at the bottom of this page.

Figure 4: SWD netting being installed for the second year in a row at Heron Pond Farm in South Hampton, NH. Photo by Jeremy DeLisle, Field Specialist, Food and Agriculture, UNH Extension

Upcoming meetings:

All Production Ag Twilight Meetings: 2023 Production Agriculture Summer Twilight Meeting | Extension (unh.edu)

June 20^th, 2023

Blueberry IPM Twilight Meeting at Stark Farm | Extension (unh.edu)

RMA Apple Insurance Listening Session:

June 27, 2023 : Goffstown, New Hampshire

10:00 a.m. to 12:00 p.m., Hillsborough County Extension Office (Large Conference Room)

329 Mast Rd., Goffstown, NH 03045

No RSVP Required

Thanks for sticking around!

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Fruit IPM Report 6/27/23

Hi all!!  

 Welcome back to the NH Fruit Pest hotline, which is produced by staff members from the UNH Cooperative Extension Food and Agriculture team.   Today is June 27^th , 2023.

 While these recordings will highlight what you need to be looking for out in the field, I highly encourage you to find the transcripts online, as they will have more details and links about many of the pests, products, and models I’ll be describing in this call. Simply google “UNH Fruit IPM reports” to find them on our webpage. The transcript for this call may not be up until Wednesday afternoon.

 In terms of growing degree days in Concord, NH we have accumulated 1193 GDD in BE base 43F and 622 GDD in BE base 50F.

Tissue Testing: Blueberry Leaf tissue testing: now & over the next few weeks is a good time to submit a sample to get an idea of any changes you may need to make to your fertilization scheme.

Soil Testing Forms | Extension (unh.edu)

Jumping into the disease update:

Apple scab:

Hopefully your orchard is clean of scab and this week will mean the end of required control measures for the growing season. While visiting orchards over the past week, scouts have spotted some scab infections present on the leaves. In those orchards, growers will need to remain diligent and maintain fungicide coverage to minimize new infections.

Here is an article addressing control and resistance management strategies for scab:

https://www.canr.msu.edu/news/management_of_apple_scab_in_orchards_with_existing_scab_lesions

The weather this week has been conducive to infection periods. If new infections are showing up in your orchard, control measures are warranted. The NEWA model for Concord shows infection events each day from June 25^th through June 30^th.

An excellent description of the factors to consider for best fungicide selection can be found here: https://netreefruit.org/apples/diseases/apple-scab

 Fire blight:

Continue to scout orchards for shoot blight, including rootstock sucker infections. Prune and remove infected shoots at least 12-18 inches below the infected margin during cool, dry weather.

Pruning is particularly useful when blossom blight is well controlled and canker blight infections are thus the main source of inoculum for disease spread during the summer. Pruning can help limit disease spread but will be most effective if practiced rigorously during the first few weeks after bloom; pruning will do little to slow disease spread if delayed until a large number of infections are visible.

Routine use of antibiotics to prevent shoot blight spread during the summer is not effective or recommended. However, applications to protect new wounds immediately following a hailstorm can be very beneficial. With a cool and dry bloom period, some growers made it through the prime infection period with just a couple of streptomycin applications. Keep in mind that saving at least one or the four allotted strep sprays in case of hail or damaging wind events is a good insurance strategy.

In a recent report, Kathleen Leahy reminds us of an article from Good Fruit Grower highlighting recent research comparing cutting and sanitization strategies to find the best removal methods for fire blight strikes. It is worth the read:

Good to Know: Take a bite out of blight - Good Fruit Grower

Fire Blight | New England Tree Fruit Management Guide (netreefruit.org)

 Sooty Blotch and Flyspeck:

Now is the time to think about how you will manage Sooty Blotch and Flyspeck in your orchard.  Check out the New England Tree fruit management guide for more info (Sooty Blotch and Flyspeck | New England Tree Fruit Management Guide (netreefruit.org)), and remember that NEWA also provides forecasting and management recommendations for this disease complex:

From NEWA: Sooty Blotch and Flyspeck | NEWA (cornell.edu)

To effectively limit fruit finish blemishes from Sooty Blotch and Flyspeck infection consider making a cover application of one of the following fungicides/tank mixes:

 Moving onto the Insects:

Apple Maggot

By the end of today we are predicted to have accumulated 706 DD base 50F from January 1, and the predicted first emergence of apple maggot occurs after approximately 796 to 1072 degree days have accumulated… indicating that traps should be up this week. The first apple maggot flies were captured in Massachusetts this week.

Apple maggot fly (AM) | New England Tree Fruit Management Guide (netreefruit.org)

 SWD – Spotted Wing Drosophila:

For the second week in a row our IPM scout has reported zero trap captures in seven traps spread over four farms in southern NH. Traps should be up now, as we typically start to catch this insect this week into next in the southern half of NH. To clarify, SWD is primarily a pest of small fruits, but also impacts stone fruits. Considering the fact that most stone fruits were lost due to severe cold this winter, controlling this pest will be generally limited to very late strawberries, blueberries, brambles and grapes.

 Codling moth:

In Canterbury, we established the biofix date of 5/26/23 to start the codling moth model within NEWA for apples and have reduced the frequency of trap checking for this insect to once a week. Once sustained trap captures have been observed, enter the biofix date for your farm into the NEWA model to track development of the pest.

Egg hatch is well underway. Control sprays critical, apply a second spray 10-14 days after the initial egg hatch spray. In Codling moth high-risk orchards, you can also consider choosing products that also target OFM and Plum curculio.

The chart below summarized control recommendations based on monitoring, biofix date and seasonal weather (DD accumulations). This chart was summarized by Dr. Jaime Pinero, UMass Extension Entomologist.

Codling moth (CM) | New England Tree Fruit Management Guide (netreefruit.org)
 

Figure 1: Codling moth trap captures for Merrimack County

Oriental Fruit Moth:

Oriental Fruit Moth (OFM) | New England Tree Fruit Management Guide (netreefruit.org)

Figure 2: Oriental Fruit Moth trap captures for Merrimack County

Oblique Banded Leaf Rollers:

Traps are up but we have yet to catch OBLR. Controls should be timed with egg hatch. Continue to monitor traps, establish the biofix date on your farm, and enter into the NEWA model to track development based on growing degree days.

https://newa.cornell.edu/obliquebanded-leafroller

Obliquebanded leafroller (OBLR) | New England Tree Fruit Management Guide (netreefruit.org)

San Jose Scale

First generation nymphs should soon be secreting new scale covers and developing into adults. The time for controlling first generation nymphs is ending. Pheromone traps should be in place in time to record the second adult male flight.

San Jose scale (SJS) | New England Tree Fruit Management Guide (netreefruit.org)

Upcoming meetings:

All Production Ag Twilight Meetings: 2023 Production Agriculture Summer Twilight Meeting | Extension (unh.edu)

Tree Fruit Twilight Meeting at Apple Hill Farm | Extension (unh.edu)

Apple Hill Farm, Concord, NH

August 17^th 5:30-7:30 pm

Produce Food Safety and Insurance Twilight Meeting | Extension (unh.edu)

June 29^th 6-8 pm in Lancaster NH – Register online.

Mid-Season Corn Checkup and Pest Scouting, Stuart Farm | Extension (unh.edu)

June 29^th 11 am – 1 pm

Stratham, NH

Thanks for sticking around!

Monitoring Spotted Wing Drosophila (SWD) with Traps (recently updated by Anna Wallingford, Assistant State Specialist, Associate Research Professor, and excellent entomologist)

Spotted wing drosophila (SWD) attacks ripening and ripe raspberries, blackberries, blueberries, grapes, cranberries, late cherries, fall strawberries, plums and peaches, plus fruit of many wild hosts. If you wish to protect your fruit from becoming infested, it is critical to set up traps for the insects, and to monitor those traps weekly when you have ripening crop present. The first flies will probably be trapped between July 2 and 12, and numbers will peak in September or October.

These traps ARE NOT TO CONTROL the flies! Once you detect flies, the crop should be protected with insecticides. Most of the good insecticides should give about seven days of protection, but can be washed off by rain. After you spray, set out fresh traps to determine when crops become at risk again.

Commercial vs. Home-Made Traps

When SWD first appeared in NH, the commercial traps that existed were not effective in comparison with home-made traps. However, effective commercial traps and baits are now available from both Scentry and Trécé, that are hung in jar traps full of soapy water as drowning solution. More recently, Trécé has marketed their lure with red sticky traps as a “dry trap” alternative to traps with water drowning solutions. All trapping types have their own pros and cons in terms of logistics of use but all are excellent at determining presence or absence of flies in susceptible crops.

In our UNH Cooperative Extension monitoring program, we are now using Trécé traps and lures for SWD. These traps are reusable, and are available from standard suppliers of IPM products (e.g. Great Lakes IPM).

When to set up the traps? Do this as soon as fruit starts to ripen. Fruits that ripen before July 1 are not likely to be at risk. You can stop monitoring when harvest of susceptible crops is over for you.

Where to set the traps? Set the traps IN the crop, in the shade, AMONG THE FOLIAGE near fruit. We recommend checking traps every 5-6 days at first, moving to every 3-5 days in August (hot weather). As the weather cools, you can lengthen the check interval. Keep checking as long as you have ripe fruit to protect.

Which crops need protection? The most susceptible crops seem to be raspberries, blueberries and strawberries that ripen in August-September; thin-skinned, dark-colored grapes; and some peaches and plums (especially white-fleshed peaches). We don’t know how heavily currants and cranberries are attacked.

How many traps do I need?  For most plantings, three well-placed traps should be enough and you should base management actions on an average of the number of flies you trap in each block. If you have different crops, you’ll want traps in each crop, because the pattern of attack varies crop-to-crop. If you have different varieties of the same crop, begin monitoring in the first variety to ripen, and move the traps to others with ripe fruit when harvest wanes on that first variety. If your crop is in several blocks that are managed (e.g. sprayed) separately, you will need traps in each block.

How do I check the traps?  Check traps at least once per week. To check the trap, remove the lid, and pour the liquid bait into a shallow white pan or saucer. In bright light, look for the male flies (they are about 2mm long, with light tan body, red/orange eyes, and have a dot near the tip of each wing) with a 2X magnifying glass. When done counting the male SWD’s, write the number down. If you find male flies, your crop is at risk. If your threshold for risk is a little higher, you can wait until you find an average of 5 male SWD in all three traps. Find this example of a sliding scale of risk for SWD infestation in wild blueberry https://extension.umaine.edu/blueberries/factsheets/insects/210-spotted-wing-drosophila/

Making Your Own Traps

From 2012-2016, we and many colleagues across the Northeast set out hundreds of traps, and learned what combinations worked well enough to make trapping a useful tool. Most of these baits relied on odors from fermentation to attract flies, including apple cider vinegar, wine, grape juice, yeasts, sugars, bread doughs, etc. Many of these bait recipes are messy, smell, and trap many non-target insects that make detection of SWD difficult. Poorly set or designed traps do not work well enough to predict when you need to protect crops. If you prefer to make your own traps rather than purchase traps, the following tips may help.

This trap design works well: We use red plastic 18 oz Solo cups with transparent lids. We placed a black band of electrician’s tape a bit below the rim. We used a heated nail to melt 1/8 inch holes in the cup, to allow the insects to get in, and the odor to escape. We don’t make those holes too large, or wasps will get in. We placed the entrance holes in and around that band, about 30 to 35 holes per trap. We leave one sector of the cup without holes, to make it easy to pour out and examine the liquid bait, without spilling any.

Add just a drop or two of liquid soap to the bait. Non-scented soap is preferable as flowery-scented soaps might decrease bait effectiveness. The soap decreases the surface tension of the bait, making it easier for the small flies to fall in and drown.

When we used the dough baits, the solid yeast/dough bait was placed inside a smaller 4-oz lidded cup within the larger 18-oz trap. We cut a hole (1-inch diameter) in the lid. Over the hole we placed fine insect netting, and fastened it with a hot glue gun. The netting is to allow the yeast odor out, but not let flies in. So the assembled trap is a large red cup. Inside that is 2 oz of liquid bait, and floating upright in the liquid bait is the smaller cup with the netted lid.

When check traps containing attractive baits, make sure to collect the old liquid bait in a waste container, and add fresh bait to the trap. Don’t pour the old bait on the ground in your fruit planting, or it will compete with your traps for the flies’ attention.

Point of interest:

UNH Extension, USDA Natural Resources Conservation Service and the NH Conservation Districts have been partnering on a three-year demonstration project investigating the efficacy, ease of use, cost of installation and potential return on investments associated with installing SWD exclusion netting systems on three farms here in NH. Those partner farms are Bascom Road Blueberry Farm in Newport, Stark Farm in Dunbarton, and Heron Pond Farm in South Hampton. To date, the systems have been highly effective at excluding SWD flies, with zero trap captures reported to date, along with no loss due to infested fruit. To learn more about the types of systems being installed and the potential for new construction versus retrofitting existing bird netting structures, join us at our upcoming twilight meeting on August 3^rd  at Heron Pond Farm.

Figure 3: SWD netting being installed for the second year in a row at Heron Pond Farm in South Hampton, NH. Photo by Jeremy DeLisle, Field Specialist, Food and Agriculture, UNH Extension

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Fruit IPM Report 7/11/23

Hi all!!  

 Welcome back to the NH Fruit Pest hotline, which is produced by staff members from the UNH Cooperative Extension Food and Agriculture team.   Today is July 11^th , 2023.

While these recordings will highlight what you need to be looking for out in the field, I highly encourage you to find the transcripts online, as they will have more details and links about many of the pests, products, and models I’ll be describing in this call. Simply google “UNH Fruit IPM reports” to find them on our webpage. The transcript for this call may not be up until Wednesday afternoon.

In terms of growing degree days in Concord, NH we have accumulated 1600 GDD in BE base 43F and 931 GDD in BE base 50F.

Weekly pest and disease update:

Mummy berry:

Mummy berry is being reported from some blueberry plantings. Details about this disease and management strategies can be found here.

Diseases | Center for Agriculture, Food, and the Environment (umass.edu)

Bitter rot:

Conditions have been good for this fungal disease with lots of rain, and quite a bit of fruit showing some sort of injury (notably, cracking) that might allow entry to the pathogen. Captan does a pretty good job, especially at slightly elevated rates. PennState cites Merivon/Pristine, Flint/Luna Sensation, Aprovia, and Omega, mixed with Captan as being effective.

Symptoms will appear now-August, with fruit getting more susceptible as they mature. Bitter rot is more common on light or bicolored fruit such as Empire, Honeycrisp, McIntosh, Sunrise, Paula red and Jonagold.

Bitter Rot | New England Tree Fruit Management Guide (netreefruit.org)

Apple scab:

The weather this week has been conducive to infection periods. If new infections are showing up in your orchard, control measures are warranted.  Most orchards are free of it, but extension staff have seem some lesions out in the field when scouting. In those orchards, growers will need to remain diligent and maintain fungicide coverage to minimize new infections.

Here is an article addressing control and resistance management strategies for scab:

https://www.canr.msu.edu/news/management_of_apple_scab_in_orchards_with_existing_scab_lesions

An excellent description of the factors to consider for best fungicide selection can be found here: https://netreefruit.org/apples/diseases/apple-scab

Fire blight:

Fire Blight | New England Tree Fruit Management Guide (netreefruit.org)

Continue to scout orchards for shoot blight, including rootstock sucker infections. Prune and remove infected shoots at least 12-18 inches below the infected margin during cool, dry weather.

Pruning is particularly useful when blossom blight is well controlled and canker blight infections are thus the main source of inoculum for disease spread during the summer. Pruning can help limit disease spread but will be most effective if practiced rigorously during the first few weeks after bloom; pruning will do little to slow disease spread if delayed until a large number of infections are visible.

Routine use of antibiotics to prevent shoot blight spread during the summer is not effective or recommended. However, applications to protect new wounds immediately following a hailstorm can be very beneficial. With a cool and fairly dry bloom period, some growers made in through the prime infection period with just a couple of streptomycin applications. Keep in mind that saving at least one or the four allotted strep sprays in case of hail or damaging wind events is a good insurance strategy.

In a recent report, Kathleen Leahy reminds us of an article from Good Fruit Grower highlighting recent research comparing cutting and sanitization strategies to find the best removal methods for fire blight strikes. It’s definitely worth the read:

Good to Know: Take a bite out of blight - Good Fruit Grower

Sooty Blotch and Flyspeck:

Now is the time to think about how you will manage Sooty Blotch and Flyspeck in your orchard. 
Check out the New England Tree fruit management guide for more info (Sooty Blotch and Flyspeck | New England Tree Fruit Management Guide (netreefruit.org)), and remember that NEWA also provides forecasting and management recommendations for this disease complex:

From NEWA: Sooty Blotch and Flyspeck | NEWA (cornell.edu)

To effectively limit fruit finish blemishes from Sooty Blotch and Flyspeck infection consider making a cover application of one of the following fungicides/tank mixes:

Figure 1:  Recommendations from NEWA for Sooty Blotch and Flyspeck.

Insects

Apple Maggot

Predicted first emergence of AM occurs after approximately 796 to 1072 degree days have accumulated. Today we have accumulated 931 DD base 50F from January 1. Set sticky traps along vulnerable field edges. Check at least weekly and note the first date of captures. Enter this into the Apple Maggot tool on NEWA.

The action threshold is an average of 1-2 AMF on the yellow cards or in unbaited sticky spheres, or a cumulative average of 5 AMF per trap on baited spheres. Trap captures for a week following insecticide treatment are ignored. Subsequent sprays can be applied once the threshold is reached again.

Apple Maggot tool on NEWA: Apple Maggot | NEWA (cornell.edu)

Apple maggot fly (AM) | New England Tree Fruit Management Guide (netreefruit.org)

 SWD – Spotted Wing Drosophila:

Traps should be up now. Trap captures spiked last week in the southern half of NH. To clarify, SWD is primarily a pest of small fruits, but also impacts stone fruits. Considering the fact that most stone fruits were lost due to severe cold this winter, controlling this pest will be generally limited to very late strawberries, blueberries, brambles and grapes.

For more information about making your own SWD traps or purchasing them, refer to past reports or refer to: Fruit: Spotted Wing Drosophila Management | Center for Agriculture, Food, and the Environment at UMass Amherst.

Point of Interest: SWD Exclusion Netting Systems

UNH Extension, USDA Natural Resources Conservation Service and the NH Conservation Districts have been partnering on a three-year demonstration project investigating the efficacy, ease of use, cost of installation and potential return on investments associated with installing SWD exclusion netting systems on three farms here in NH. Those partner farms are Bascom Road Blueberry Farm in Newport, Stark Farm in Dunbarton, and Heron Pond Farm in South Hampton. To date, the systems have been highly effective at excluding SWD flies, with zero trap captures reported to date, along with no loss due to infested fruit. To learn more about the types of systems being installed and the potential for new construction versus retrofitting existing bird netting structures, join us at our upcoming twilight meeting on August 3^rd at Heron Pond Farm in South Hampton, NH. Details are available at the link at the bottom of this page.

Blueberry Maggot Fly:

 Traps should be up now. Flight is expected this week if not already occurring in some locations. Details on monitoring and management can be found here.

Fruit: Blueberry IPM - Blueberry Maggot Fly | Center for Agriculture, Food, and the Environment at UMass Amherst

Codling moth:

Figure 2: Codling moth trap captures for Merrimack County

Oriental Fruit Moth:

Oriental Fruit Moth (OFM) | New England Tree Fruit Management Guide (netreefruit.org)

Figure 3: Oriental Fruit Moth (OFM) trap captures for Merrimack County

Extension traps are continuing to catch Codling moths in Canterbury.  

The chart below summarizes control recommendations based on monitoring, biofix date and seasonal weather (DD accumulations). This chart was summarized by Dr. Jaime Pinero, UMass Extension Entomologist.

Oblique Banded Leaf Rollers:

Traps are up and we have finally caught our first and only OBLR. Controls should be timed with egg hatch. Continue to monitor traps, establish the biofix date on your farm, and enter into the NEWA model to track development based on growing degree days.

https://newa.cornell.edu/obliquebanded-leafroller

San Jose Scale: (Apples)

First generation nymphs should soon be secreting new scale covers and developing into adults. The time for controlling first generation nymphs is ending. Pheromone traps should be in place in time to record the second adult male flight.

San Jose scale (SJS) | New England Tree Fruit Management Guide (netreefruit.org)

Tissue testing time is here for some crops and coming right up for others.

Directions for taking a plant tissue sample leaf sample in your orchard/garden:

Tips - In general, it is usually best to sample many plants (with only a few leaves from each plant) rather than sample many leaves from only a few plants.

Select the youngest, fully developed (mature) leaves for analysis. Do not select leaves from plants which are mechanically damaged, insect damaged, diseased or dead. Avoid leaves from border plants or leaves which are fully shaded by other foliage. Do not send sample plants that have been under prolonged stress.

Avoid leaves which are contaminated with soil or dust or which have been recently sprayed. In general, plant leaves which have been exposed to normal rainfall are sufficiently clean for analysis. Samples can be washed briefly in a 2% non-phosphorus detergent solution and then rinsed carefully with clear water. However, in many situations the cleaning may do more harm than good.

If you are trying to diagnosis a problem and are sampling plants that are showing an abnormal symptom, follow the above directions, but sample only from plants showing the problem.

Crop Information

Blueberries: sample at least 40 leaves from 10 to 20 plants during the first week of harvest.

Strawberries: sample at least 40 first fully expanded leaves from 10 to 20 plants, after renovation

Brambles: sample at least 60 leaves from 10 to 20 non-fruiting canes during early-mid August.

Grapes: sample 50 to 75 of the youngest full-expanded leaves from 10 to 20 vines at veraison (70 days after bloom, as the first fruit ripens). Separate petioles (leaf stems) from leaves, and send only the petioles for analysis.

Tree fruits: sample 5 leaves from each of 10 trees from late July through early August. Select shoots at eye-level from around the outside of the trees that make a vertical angle of 45-60 degrees to the ground (avoid water shoots or suckers). Collect leaves from the mid-portion of the new shoot growth.

For other crops: Contact your local field specialist or county office to determine the correct sampling procedures. After Collection Samples should be placed in paper bags and air dried (turn the bag frequently) or dried at 200 degrees Fahrenheit.

If you wish to submit sample to UNH for tissue sampling, more information and forms can be found here:

Form: UNH Cooperative Extension - Commercial Plant Tissue Form.pdf - All Documents (sharepoint.com)

Main soil/tissue testing site: Soil Testing Services | Extension (unh.edu)

Upcoming Events

August 3 - Blueberry IPM Twilight Meeting at Heron Pond Farm | Extension (unh.edu)

August 17^th - Tree Fruit Twilight Meeting at Apple Hill Farm | Extension (unh.edu)

See the full list of twilight meetings here:

2023 Production Agriculture Summer Twilight Meeting | Extension (unh.edu)

Thanks for tuning in!

Back to Top

Welcome back to the NH Fruit Pest hotline, which is produced by staff members from the UNH Cooperative Extension Food and Agriculture team.   Today is July 25^th , 2023.

While these recordings will highlight what you need to be looking for out in the field, I highly encourage you to find the transcripts online, as they will have more details and links about many of the pests, products, and models I’ll be describing in this call. Simply google “UNH Fruit IPM reports” to find them on our webpage. The transcript for this call may not be up until Wednesday afternoon.

In terms of growing degree days in Concord, NH we have accumulated 1991 GDD in BE base 43F and 1231 GDD in BE base 50F.

Weekly pest and disease update:

Diseases:

Mummy berry on blueberry:

Is being reported from some blueberry plantings. Details about this disease and management strategies can be found here.

This infects new shoots in the very early spring beginning around budbreak. Those infected shoots can then in turn release spores that infect open flowers, eventually resulting in the symptoms you are seeing in your berries. The fruit you see there will eventually shrivel and look like a little grey or black pumpkin. This lies in waiting until next spring for conditions to be just right and releases new spores to continue the cycle. You can read more about the disease here: Microsoft Word - Blueberry IPM - Mummy Berry Final.docx (umass.edu)

This year was certainly a good weather year for this fungus. We had temperatures conducive for extended persistence of apothecia. As noted in the fact sheet below, as apothecia expand, the number of ascospores released increases. Ascospore discharge depends on temperature, relative humidity, and wind speed. Apothecia can persist for about 3 to 4 weeks under cool conditions — 50° to 59°F  — but are shorter lived as temperatures rise. At 68° to 77ºF (20° to 25°C), they may persist for only 1 to 2 weeks.  We had damage from the freeze, which likely damaged plant tissues and made them more susceptible to infection. Did you see many shoot strikes? These would've been visible around the time that flowers were present. The fact sheet below gives detailed information about the disease cycle and includes photos of berries as the life cycle progresses. I know many of you are familiar with this, but there is good information in there and helpful pictures.

https://www.canr.msu.edu/blueberries/uploads/files/E2846%20Mummy%20Berry%20Facts.pdf

A list of fungicides and their efficacy is also included in the fact sheet above.

Mulching with at least 2” of fresh mulch in the fall can also greatly help reduce the number of spores that are able to reach susceptible tissue. This strategy can’t be used year after year due to too much mulch buildup, but if you need to mulch, this fall would be a great time for this reason. Also, picking off as many of those suspicious fruits as possible will only help to reduce potential inoculum for next season.

One last tip…You could collect 10-20 of the mummies and create a “mummy garden”. I know, it sounds funny, but you could place them outside the planting, possibly just nestled in some wood mulch (not fully buried) and use that to track the development of the disease development next year. Once you see the little mushroom cups coming up, it will clue you in as to when you need to treat. Research shows that the fruiting bodies of the fungus (apothecia) need to be at least 1/12” in diameter to produce spores for infection.

Moving onto the apples:

Bitter Rot:

Conditions have been good for this disease with lots of rain, and quite a bit of fruit showing some sort of injury (notably, cracking) that might allow entry to the pathogen. Captan does a pretty good job, especially at slightly elevated rates. PennState cites Merivon/Pristine, Flint/Luna Sensation, Aprovia, and Omega, mixed with Captan as being effective.

For more info: Apple and Pear Disease - Bitter Rot (psu.edu) and Bitter Rot | New England Tree Fruit Management Guide (netreefruit.org)

Apple scab:

 Hopefully your orchard is clean of scab for the growing season. While visiting orchards, Extension staff have seen some scab infections present on leaves. In those orchards, growers will need to remain diligent and maintain fungicide coverage to minimize new infections.

Here is an article addressing control and resistance management strategies for scab:

https://www.canr.msu.edu/news/management_of_apple_scab_in_orchards_with_existing_scab_lesions

An excellent description of the factors to consider for best fungicide selection can be found here: https://netreefruit.org/apples/diseases/apple-scab

Our new Plant Diagnostic Lab Director, Dr. Bo Liu, has been busy along with other lab staff members diagnosing all sorts of plant diseases this summer. Below I have included his report along with microscope images provided by his lab of two fungal pathogens, apple scab and Alternaria leaf blotch.

Figure 1: Apple Scab:  Leaf spots with dark brown to black lesions were on apple leaves. Several leaves collected and samples were checked under microscope, observing the microbial structure, and isolations were performed on Potato Dextrose Agar (PDA) for 10 days. A total of 5 lesions were recorded along with the fungal isolates recovered. An overall assessment was made based on the evaluations including signs and symptoms observed on leaf surfaces (Fig. 1), recovery of the organisms involved (Fig. 2)

Figure 2

Alternaria leaf blotch: Lesions on leaves (figure 3) are circular, necrotic lesions with a light brown interior, and some were surrounded by a darker purple ring. Several leaves collected and samples were checked under microscope (figure 4) for observing the microbial structure, and isolations were performed on Potato Dextrose Agar (PDA) for 10 days.

Figure 3: Symptoms of Alternaria Leaf blotch on apple leaves with circular and necrotic lesions.

Figure 4: Conidia morphology (Alternaria mali) on the lesions of apple leaves.

A small amount of information regarding management of Alternaria can be found here.

Fire blight:

There has been plenty of fireblight popping up on apple orchards around the state from southern New Hampshire all the way up into Carroll County.

Continue to scout orchards for shoot blight, including rootstock sucker infections. Prune and remove infected shoots at least 12-18 inches below the infected margin during cool, dry weather.

Pruning is particularly useful when blossom blight is well controlled and canker blight infections are thus the main source of inoculum for disease spread during the summer. Pruning can help limit disease spread but will be most effective if practiced rigorously during the first few weeks after bloom; pruning will do little to slow disease spread if delayed until a large number of infections are visible.

Routine use of antibiotics to prevent shoot blight spread during the summer is not effective or recommended. However, applications to protect new wounds immediately following a hailstorm can be very beneficial. With a cool and fairly dry bloom period, some growers made in through the prime infection period with just a couple of streptomycin applications. Keep in mind that saving at least one or the four allotted strep sprays in case of hail or damaging wind events is a good insurance strategy.

In a recent report, Kathleen Leahy reminds us of an article from Good Fruit Grower highlighting recent research comparing cutting and sanitization strategies to find the best removal methods for fire blight strikes. It’s definitely worth the read:

Good to Know: Take a bite out of blight - Good Fruit Grower

Another great resource on fireblight management options come from Dr. Kari Peter, Tree Fruit Pathologist at Penn State University. Her presentation from our UNH Fireblight Webinar can be accessed here.

Sooty Blotch and Flyspeck:

Now is the time to think about how you will manage Sooty Blotch and Flyspeck in your orchard. 
Check out the New England Tree fruit management guide for more info (Sooty Blotch and Flyspeck | New England Tree Fruit Management Guide (netreefruit.org)), and remember that NEWA also provides forecasting and management recommendations for this disease complex:

From NEWA: Sooty Blotch and Flyspeck | NEWA (cornell.edu)

To effectively limit fruit finish blemishes from Sooty Blotch and Flyspeck infection consider making a cover application of one of the following fungicides/tank mixes:

Figure 1:  Recommendations from NEWA for Sooty Blotch and Flyspeck.

Insects:

Blueberry Maggot Fly

The blueberry maggot degree day model predicts when to set baited traps to monitor for adult flies. This insect has patchy distribution and monitoring will determine if and when it occurs on your farm. Flies typically emerge around 913 degree days base 50˚ F from January 1.

Blueberry maggot flight places the crop at risk from egg-laying females.

Continue to check blueberry traps once or twice per week, as required, and replace traps and baits every third week. If caught, begin insecticide treatment. Maintain an IPM and insecticide program to protect the crop, according to your market requirements. After harvest, remove and discard used traps and bait.

Blueberry Fruit Fly [fact sheet] | Extension (unh.edu)’

Apple Maggot Fly

Predicted first emergence of AM occurs after approximately 796 to 1072 degree days have accumulated. Today we have accumulated 1231 DD base 50F from January 1. Set sticky traps along vulnerable field edges. Check at least weekly and not the first date of captures. Enter this into the Apple Maggot tool on NEWA.

The action threshold is an average of 1-2 AMF on the yellow cards or in unbaited sticky spheres, or a cumulative average of 5 AMF per trap on baited spheres. Trap captures for a week following insecticide treatment are ignored. Subsequent sprays can be applied once the threshold is reached again.

Figure 5: Unbaited red sticky sphere for monitoring apple maggot fly in orchards. Photo: Jeremy DeLisle

Japanese Beetles:

Adult beetles can be found feeding on foliage and fruit currently throughout most of NH. Many of us are interested in opportunities for mass trapping this pest. Blueberries and raspberries are especially attractive to this insect. There may be hope yet for Japanese beetle traps that can actually help control populations and limit damage to fruiting crops. Visit the link here for more information.

SWD:

Traps should be up now. Trap captures last week were relatively low in the southern half of NH. This does not mean that the threat from this pest is over. More likely, the actions that growers took to control this pest in response to high number the previous week have knocked the population of adults back temporarily.

This morning Extension staff made a site visit to an unsprayed red raspberry planting in the Loudon area. After explaining the importance of frequent picking and cold storage (refrigeration or freezing) as part of the SWD tolerance strategy, I picked the first two ripe berries I saw and was easily able to locate SWD larvae in those ripe berries.

Note: Raspberries and blueberries can tolerate cold storage temperatures close to 32° F, so don't be afraid to put your fruit in a cold storage to keep it crisp and fresh and kill or slow down SWD egg and larval development (NYS IPM).

SWD is primarily a pest of small fruits, but also impacts stone fruits. Considering the fact that most stone fruits were lost due to severe cold this winter, controlling this pest will be generally limited to blueberries, brambles and grapes at this point in the season.

You can find more info about SWD and SWD trap selection in past pest reports, refer to the ones from this past June!

Notes of Interest:

UNH Extension is trialing red sticky traps paired with the Trece Pherocon Peel-Pak lures in 2023. We also work with many growers who use the drowning traps paired with these same lures. In the photo below, the smaller red square is the lure, while the red rectangle is the sticky trap, which gets checked weekly.

Figure 6: : New red sticky traps to capture SWD. Photo: Jeremy DeLisle

SWD Netting Project

UNH Extension, USDA Natural Resources Conservation Service and the NH Conservation Districts have been partnering on a three-year demonstration project investigating the efficacy, ease of use, cost of installation and potential return on investments associated with installing SWD exclusion netting systems on three farms here in NH. Those partner farms are Bascom Road Blueberry Farm in Newport, Stark Farm in Dunbarton, and Heron Pond Farm in South Hampton. To date, the systems have been highly effective at excluding SWD flies. To learn more about the types of systems being installed and the potential for new construction versus retrofitting existing bird netting structures, join us at our upcoming twilight meeting on August 3^rd at Heron Pond Farm in South Hampton, NH. Details are available at the link at the bottom of this page.

Apple Pests:

Codling moth:

Trap captures finally decreased significantly towards the end of last week. We are currently at 1052 DD past our biofix, indicating that first egg hatch of the second generation should begin soon.  Below is a resource shared by Dr. Jaime Pinero at UMass outlining a control approach based on trap captures and degree day accumulations targeting larvae at egg hatch.

Codling moth (CM) | New England Tree Fruit Management Guide (netreefruit.org)