Managing Insect Pests in the Vegetable Garden, Ground Cherries and Choosing Your Battles [audio]
While insects are a part of every garden, and an important part at that, there are some insects that cause unacceptable damage to our plants and need to be managed as pests. In this episode of Granite State Gardening, UNH Extension’s Emma Erler and Nate Bernitz are joined by Anna Wallingford, host of the Overinformed on IPM podcast, to share proven tips and solutions for managing these insect pests with an integrated pest management approach. Anna has an uncanny ability to make pest management fun, and while she focuses on advising farmers, recording this episode was a unique opportunity to bring her expertise to gardeners. Anna shares unexpectedly interesting information about the lives these insects lead, and how understanding their life cycles and peculiarities can give gardeners a leg up in battling these garden foes.
· Featured Plant: Ground Cherries (Physalis pruinosa)
· Closing Tip: Choosing your battles with pests in the garden
Email us questions, suggestions and feedback at firstname.lastname@example.org
Transcript Pending by Otter.ai
Emma E 0:00
We often have people send us pictures of caterpillars wondering if they should kill it because it's doing some damage to their plant. But often there's there's a lot of good guys too.
Nate Bernitz 0:09
Maybe it's munching a little bit on the leaf of one of your veggies. That insect may not be a pest at all. And not only might you be killing something unnecessarily, but you may be taking out beneficials along with not not what we want to do.
Greetings Granite State gardeners, I'm Nate Burnett's joined as always by horticulturist and UNH extension field specialist Emma hurler, and today by a special guest, Anna Wallingford. So Anna is the host of another UNH extension podcast. Anna has more than 15 years of experience studying pest insects and diseases affecting fruits, vegetables and ornamental commodities throughout the country. Her role in the state is to work directly with colleagues and with the state's agricultural producers to implement strategies for sustainable management of crop pests. Anna is an extensions state specialist in entomology and integrated pest management. Anna what would you like to add to that introduction? Tell us about yourself and about your podcast?
Anna Wallingford 1:24
Well, gosh, I've been working in Applied Research, you know, attempting to find solutions to people's new and emerging pest problems, and new new and creative ways to incorporate IPM tools into their system, but over informed on IPM the title implies that I'm constantly over informing people against their will. And I wanted to make it optional. So the thinking on that podcast is to say, what do you need to know about managing this past and then like, I have a whole bunch of stuff to tell you about what me and my friends and colleagues are doing to study the biology of this, these insects that impact our lives negatively.
Nate Bernitz 2:05
It's a really fun podcast, I recommend it. It's not necessarily geared towards gardeners, but I think it definitely piques my intellectual curiosity. The episodes are short, they're spiffy, they're fun. You make science interesting. You're just an awesome science communicator. And yeah, we'll have the link to that in the show notes over and formed on IPM. I want to start by asking both of you what you've been noticing in the fields, or just from talking to clients to gardeners were to farmers, Anna, what seems to be a particular issue this year.
Anna Wallingford 2:41
Gosh, this year, I am scratching my head over what to do about cut worms. So this is something that is definitely impacting commercial growers, especially people who grow a lot of greens. So you know a lot of our especially CSA, gardeners market farmers. They will have a steady drumbeat of greens via brassica greens, lettuces, things like that. We're finding a lot of people who are having their greens being eaten up by usually nocturnally active caterpillars, right? So we're used to cut worms that like you have some transplants in the ground, and you come back the next day and those transplants are gone. It might be a cut worm that's living below ground. This is something different. And I haven't really nailed down what species is causing this problem. It might be dingy cut worm, it might be variegated cut worm, it might be a somewhat new cut worm called winter cut worm, or I'm trying to think of the other name of it. But there's something going on where these species of caterpillars that live in the soil. They overwinter in the soil, they would have been laid by a moth last summer. We're just seeing more and more of them. And we don't know if it's because there's more overwintering success. Typically, a lot of these species just don't fare well in New England winters. And they're they're faring very well. That might be for a few different reasons. It might be you know, because of climate change, it might be because more people are using high tunnels or season extension techniques. And it may very well be because we're doing such a great job of maintaining high organic matter. So as you're making changes in the way that you grow things, you're encountering, you know, kind of kind of new situations. So that's something where you're seeing these caterpillars feeding earlier in the season that we then we would have expected
Nate Bernitz 4:33
Emma and I did an episode on nuisance wildlife and I think cutworms came up in that conversation because they're a really low key under the radar pass. People often think what cut down my corn or whatever. But what's kind of unusual about cutworm damage as compared to damage from an animal is that the plant is still there.
Anna Wallingford 4:59
Yeah. Yeah, and so what makes it even more difficult for me is that finding and catching that worm red handed or red mandible is a challenge because a lot of times you have to go out at night to actually find them. If you go out in the day to try to find them, it's hard. So it's really quite difficult for me to identify what species of animals are causing this problem. So in a commercial setting, pretty much any broad spectrum pesticide will do the job. So we've never really needed to identify them. But for folks work, a pesticide does not fit into their strategy, you need to know a little bit more about that insect in order to identify when to make preventative actions or whether or not that animals overwintering and that soil. So there's the challenge there is I don't really know exactly what's causing the problem. I just kind of know what the symptom is now. And stay tuned, maybe maybe a year or two, we'll have a better understanding of what's going on.
Nate Bernitz 5:53
And so, for cutworms, I think what I've heard is that the approach is often physical exclusion, if you don't want to go after them chemically, like with some kind of color, or like something around the base of the plants, is that practical, both at a farm and garden perspective? And like, what kind of material might a gardener use to protect their precious plants?
Anna Wallingford 6:21
Oh, gosh, that is a good good question that goes back to like the proper identification of what's causing the problem. So if you have one of these, like nighttime active cutworms, that spends his day in the soil and comes above ground, I think collars have a have a place, if you're talking about some like something that that is active during the day, and you can find it, I think hand squishing is really the best way to like that, that's the most efficient way to go. If you're open to bio controls, bt products. One thing we know for sure, if we don't know the species, we know they're all lepidoptera ends. And so like a bt product that's labeled for use on caterpillars should be effective, I would apply it pretty frequently. Because you, the animal needs to eat that product in order to get sick and have some kind of effect. So some of them, some of them are dwelling below the soil and coming up, you know, chop that plant, there's this other group of cut worms that does come up and does eat the foliage. And that's what we're seeing the problem is now, yeah, so you're seeing big holes. And the group of insects that are kind of in the script, we do call them cut worms, even though it's not exactly the same behavior of what you're thinking about, which is like that black cutworm that comes up and just knocks out that that transplant. This is a little bit different.
Nate Bernitz 7:38
Oh, so you're managing that more like you would manage other caterpillars?
Anna Wallingford 7:43
Yeah. They just seem to be much more severe this year. We don't we don't really understand what's going on yet.
Nate Bernitz 7:50
Fascinating. If any gardeners are dealing with mysterious damage that is talking about and you're wondering, maybe it's a cop worm, I assume you go out at night with Do you go out with some sort of special light?
Anna Wallingford 8:03
maybe I mean, what I will say is that they with other insects that you're looking for at night, they have a possibility of dropping off the plant in response to that white light that you might have for a headlight. So I would recommend using a red light. So if you're out looking for like, I don't know, other other insects or red light is really nice because insects do not detect red. And that's actually the reason that like, cell phone towers have red lights of like anything around airports, I have red lights, it's because bugs aren't attracted to red lights. So not that you're too too worried about bugs flying around airports, they're more worried about night flying animals that eat night flying bugs. So that red light is key with cutworms I wouldn't worry about that too much. They're not going to drop off the plant in response to that. But bugs in general can't see red.
Nate Bernitz 8:53
Yeah. Emma, what are you seeing?
Emma E 8:55
You know, I've actually been seeing quite a bit of aphid activity this year. And I'm often as you know, paying more attention to trees and shrubs, but around my apartment, right now there is all sorts of aphid activity and excitingly, there's actually all sorts of Ladybug larva activity. So right outside my front door, there are a couple of burning bushes, which for folks who are familiar with those, it's an invasive species that used to be planted widely in landscapes. A lot of older landscapes still have these, these shrubs there. They have been absolutely coated with aphids this spring. So at first I was looking at from a distance was wondering what was going on because the leaves were all crinkled up on the plants. So I went up took a closer look. And sure enough, they were covered with aphids. So you've got that sticky honeydew all over the foliage and all sorts of aphid activity and because it's a burning bush, I certainly don't care. I said, Yeah, aphids. You know, do your thing. But what was really neat a couple of days ago was to see dozens of Ladybug larva, crawling all over the place all over the leaves of that burning bush, eating up the aphid larva. So if if I had panicked or if if a homeowner panicked about the aphids and treated them a couple of weeks ago, that means there wouldn't have been all this really excellent food for the ladybug larva, and those those shrubs, I have absolutely no concern for their health, they're going to be just fine. And it was really nothing for me to get to watch. So I don't know if other people are seeing just as many I have heard from, you know, a number of gardeners that they're seeing a lot of aphids in their gardens this year. But hopefully they're seeing some Ladybug larva out there now to.
Nate Bernitz 10:51
let me read an email from a gardener dealing with aphids. So this is from Deb, three tomato plants and two bean plants that are young about a foot to a foot and a half tall right now. She planted them as seedlings three weeks ago, but ended up digging them up and bringing them inside because they looked so weak from aphids. And then when they recovered, she said she replanted them last weekend. But the aphids were still there. She thought by bringing them inside. The aphids wouldn't have anything to eat and might go away. But that was not the case. And she has been hand squashing them. And she's wondering if this is just going to get worse and worse, or she should be doing something else besides daily handpicking. She said she's considering spraying neem oil and is wondering where are all the ladybugs?
Anna Wallingford 11:42
Well, the ladybugs might not have been active yet. That might be where they haven't gotten a chance to find them. Nate, do you think that the the tomato transplants like do you think that they might have come to her infested with aphids?
Nate Bernitz 11:57
I'm just assuming she started them from seed and that the aphids may have come from elsewhere from out in the garden from weeds or something surrounding the plants.
Anna Wallingford 12:08
Okay, so bear with me, I'm gonna walk you through aphid lifecycles Yes, I know, this seems like more information than you might need. But it'll turn you around. It's really interesting. So here in the northeast, most most aphid species overwinter lays eggs either in the soil or kind of inserted somewhere in the host tissue of a plant from last year. Those eggs are really cold hardy. And so once they go through some kind of chilling, they will hatch out into what we call the fun day tricks, right. This is a female, she hatches out, she climbs up on her host plant, she taps into it, she starts feeding as long as she has enough nutrition. She's capable of reproducing a genetically identical daughter through parthenogenesis. So she doesn't need to settle down and find somebody special and start a family she can just do it on our own right. So she will reproduce those daughters. And those daughters will reproduce daughters. So that is a big reason that effects are so difficult to control is because if you squish 99 out of 100 of them, you still have an aphid problem. So what will happen is that she'll continue to reproduce and continue to reproduce. If that plant gets too crowded. If her offspring start feeling stress and don't have the nutrition they need to reproduce and produce more genetically identical daughters, they will produce wings and fly away somewhere else. So that's how aphids do spread around during the season. Given the time of year, those plants It was too early in the year for any kind of winged aphids to fly in and land on those plants. So chances are pretty good that that aphid infestation came from the soil. So taking taking it inside would have had no impact on that aphid population. If anything, it would have made it friendlier for them because it have more mild temperatures. Really, their their growth and development is affected by their nutrition and their temperature. So the warmer it is the closer to optimal it is the happier they are to just keep pooping out those daughters and reproducing. So do you think that that answers? What what happened there as far as the infestation? Do you think that's a good guess as to what happened with her aphids?
Nate Bernitz 14:29
I'm gonna take your word for it. That sounds like a fully vetted over and form type answer. That sounds great. So the question is what she should do so maybe next time she won't dig them up and bring them inside but what's the strategy she should have used or should use now?
Anna Wallingford 14:47
Well, gosh, hands question does help a lot but she did mention neem and what I want to do is clarify what neem does and how neem works. So most of the products that You can purchase at the store that are labeled neem oil, or actually clarified neem oil. So this is a really cool story because there's a plant called the neem tree that has evolved a defense mechanism against insects that consumed the plant. Right. So it develops, it evolved to produce this compound that is actually an insect growth regulator. So any kind of insect that comes along and consumes that plant tissue consumes enough of it, that it just doesn't thrive. It doesn't make it to adulthood, so any kind of immature insect that consumes that product will come out weird, it will, it won't make it to adulthood, that hurts the population to start with. So that's where the idea came from. This is this a cold pressed neem product from the neem tree will will contain some of this chemical called is a direct in the clarified neem oil has had that material extracted from it for a couple different reasons we don't really need to get into. So if you buy neem oil that's called clarify neem oil, that's just the oil leftover. And that's not to say that that's not worthwhile, it doesn't do exactly the same thing that that other, you know, other neem products are is attracting containing products might do. The way that that oil works is that when it gets on the insects body, especially if you can really coat the insect, and it can get into the breathing holes, you might not know if it's actually insects in general breathe through their sides, right, so they have a few air holes along the sides of their body. So if you coat that insect with this product, not only does it smother it by by kind of drowning it, but that oil will also interfere with the integument or the exoskeleton skeleton of that insect and break it down and that insect will not thrive. So it's not toxic, it's not hard, it's not, it's not toxic for the insect to eat, it's not toxic for us to expose. It's no different from an oil or a soap. But for a little insect with a thin skin, it can be really detrimental to the population. So if you spray a plant with that, it's a lot easier to get in the cracks and crevices. If you're squishing bugs, it's easy to miss them. But a little bit of squishing a little bit of a little bit of oil. horticultural oil is just as good as neem oil. But that's kind of a twofer. That's your integrated approach both both both of these different approaches.
Nate Bernitz 17:22
And I'm a we're talking to Rachel, in the last episode, who recommended just a really strong stream of water from the hose.
Emma E 17:30
outdoors, I think that works really well. A lot of times, when you spray those aphids off the plant, they probably won't make it back up onto the same plant before they get found and eaten by somebody else in the Circle of Life goes on. But that's definitely something I do with plants that are in my own landscape, I might be a little hesitant to do it on tomatoes. Or if I was gonna do it on tomatoes, I'd want to do it first thing in the morning, so that the leaves aren't staying wet too long. I know we're not talking about plant diseases today. But it's something that's always good to pay attention to. If you're going to get the foliage wet on your plants, you want to do it early so that they'll dry out quickly. And hopefully we don't get fungal disease issues while we're trying to take care of insects.
Anna Wallingford 18:14
Oh, that's a huge part of integrated pest management, though you have to take into account all of them. Another thing I wouldn't bring up about this particular situation is because they were such young plants, they were probably less capable of handling a little bit of aphid damage. If that was a big mature plant. A few aphids, no big deal, because they were young, you have to be a little bit more proactive.
Nate Bernitz 18:34
My only concern about the heavy stream of water is potentially damaging the plant. Like a tomato plant doesn't have the strongest stem, you have to support it with steaks and all this stuff. And I don't know sometimes when I'm watering if I'm doing it from overhead and I'm not being careful on you know, sometimes seeing plants, limping over, they just didn't have the strong stem to withstand that and they'll problably recover.
Emma E 19:01
I think it's important to note, too that for dislodging an aphid doesn't necessarily require a fire hose spraying on the leaves of your plants. It could it could be a little bit more gentle stream so that you're not entirely blasting apart the foliage. But yeah.
Nate Bernitz 19:16
So strong by aphids standards.
Emma E 19:19
Yeah, so with a new seedling plant, yeah, the the fire hose approach with the spray nozzle is probably not appropriate.
Anna Wallingford 19:28
But point well taken with any intervention, you must obey the Hippocratic Oath first do no harm before before considering whether or not it's going to harm your target.
Emma E 19:38
That's true with some of the oils you mentioned to Anna sometimes oils can end up burning plants. So it's not always the best approach.
Anna Wallingford 19:46
Yeah, they always say do a little spot treatment if you're trying something new. But if something is marketed for use on plants, chances are pretty good. They've already vetted that. That is one of the reasons we don't necessarily recommend like dish soap. You could certainly do the same thing with dish soap with Don soap, but you run more of a risk of causing phytotoxicity in your plant. So if you want to use a home remedy for something like that, just do a little spot test on that plant and see if it reacts badly.
Nate Bernitz 20:13
Anna, you've mentioned Integrated Pest Management a bunch of times and some of the principles around it. And it's even in your professional title. So I figure you're probably a really good person to ask what is integrated pest management, and how does Integrated Pest Management become a tool for gardeners?
Anna Wallingford 20:33
Well, integrated pest management is something that was certainly developed for commercial producers first, first and foremost, but there's definitely some principles that can be applied to the home garden. So Originally, it was economic entomology. So taking into account the costs of an intervention, versus how much that pest damage might cost you. So if the pest damage wasn't going to really cause any problems to the bottom line, it doesn't make a lot of sense to spend money doing some kind of intervention like doing a biological control or a spray. A lot of times I'll say to people in garden situations or in household situations, understanding an acceptable level of damage is a really important part of integrated pest management to say, you know, there's a certain acceptable threshold. So a good example would be your threshold for mice in your house is probably zero mice. Right. So you'll take out all the tools and the IPM toolbox to handle that and get your threshold down to zero. If it's your barn, your threshold might be a little bit higher, you might be open to just like a biological control, like a cat, to maintain whatever your acceptable threshold of mice is in your barn. So we talked about a scenario with tomatoes like the young tomato plant being more susceptible than the old tomato plants. That's a situational thing as far as acceptable levels of damage. But it's it's first and foremost, identify what's causing the problem, make sure that you're correctly identifying a past before you take any action, consider all the different ways that you might be able to manage that pest in a way that gets to your final goal, which is, you know, like a healthy fruit or something, and taking into account the biology and all these different tools before you take out that pesticide. So that's the ultimate thing is to think this is often considered as a check on pesticide use, because you're considering other other tools. But chemical pesticides are certainly part of an IPM program. In many instances.
Nate Bernitz 22:39
I think there's some aspects of IPM that are really easy for gardeners to implement, and some that are really hard one of them that's really hard as crop rotation. And that matters for some pests and diseases more than others, right? Like it is a really big deal. If you're growing tomatoes for septoria leaf spot, maybe not as big of a deal for late blight. It's a really big deal for insects that overwinter in the soil, not as big of a deal for insects that fly in. Can you maybe give examples actually of insects that are managed really well by proper rotation, and some that aren't?
Anna Wallingford 23:24
Well, gosh, and a home garden situation, I think that you're right on the money with the diseases, so soil borne diseases soilborne plant parasitic nematodes, those are the kinds of things that you know, you want to pay close attention to and not not replanted with it with a similar plant species. From insects point of view. And a home garden situation, you usually don't have enough space to rotate away for most, most pests. I think the quintessential example is definitely Colorado potato beetle. So that beetle loves all solanaceous crops. So it's named Colorado potato beetle. But it also loves tomato, eggplant, peppers, anything in that family. So it will complete a couple generations in a year. So essentially, it'll overwinter as an adult, it'll come up from the ground around this time of year, start looking for a new host plant and moving into a solanaceous crop and then complete the rest of its lifecycle and kind of kind of do it over again. So that's a place where crop rotation can help even if you're moving it, you know, from one side of your property to another because and actually this year is not a great example because it got hot really fast. But in the springtime, these beetles are really limited by the temperature as far as their mobility, so they cannot fly until it gets above 80 degrees, they must walk wherever they're going. So if it was a normal spring, cool temperatures, they would have to walk from their overwintering locations to their new host. So it's much easier to intercept that. But even though it's warmer out and Fly, you could certainly intercept it with some row cover, or something like that. But yeah, rotation is is an important factor there.
Nate Bernitz 25:08
Right? If you're growing potatoes, or eggplant or something like that, and you don't rotate and use row cover, those potato beetles might come up right under your row cover, and then you are trapping them inside with your crops.
Anna Wallingford 25:25
Once they get on that host, they're probably not going anywhere. But there's certainly not a benefit of using that row cover. And it is quite a pain to keep a solid row cover when it gets windy especially.
Nate Bernitz 25:38
Yeah, row covers not particularly easy to use, especially if you're not using something like drip irrigation. Especially if you have a lot of weed issues, you're having to take that row cover off and then secure it back on and securely enough so that insects can easily just walk right under it. So definitely something that needs to be part of an overall plan. And that does require some planning as far as how you're going to deal with the weeds, how you're going to irrigate, etc.
Anna Wallingford 26:10
I think the standout feature, especially when we're talking about insects that you cannot rotate away from a lot of the flying insects that cause problems. So cabbage maggot, onion maggot, some of the leaf miners that impact beets, and other beet greens. Those insects are emerging from overwintering habitats and flying around and looking for a place to leave their children. Right. So they're responding to the host plant volatiles from a good place to leave their eggs and they're laying their eggs, those eggs are hatching, and the larva are usually burrowing into somewhere where you can't reach them. So prevention is really key with some of these fly paths. That's where maintaining a good barrier is absolutely worth the labor. And it's absolutely worth the pain in the neck to protect those plants. In some instances, you can even track the flight behavior of these based on temperature. So you don't have to necessarily protect that crop for the life of the crop, you can just protect the crop for the life of that flight period. So I'll give you the link. But we have great models for any maggot, cabbage maggot, it's the the new link, you can go on, see your local weather, it'll track it'll tell you about when they're flying about when their peak flying. And when that has tailed off, and you can just provide the most protection during that time.
Nate Bernitz 27:33
That's really a big topic. But that's really a big part of what you do in IPM, as far as being a state specialist that serves growers is that you provide those models, and you employ scouts that travel around the state and check your traps and feed you up to date information that can inform those recommendations.
Anna Wallingford 27:57
Yep. But hey, insects are pretty predictable. Like if you had an onion magnet problem last year, chances are pretty good, you're gonna have one this year and you can rely on locally occurring temperatures to predict their behavior. What I can't necessarily tell you is how bad your problem is. So I can't tell you whether or not you absolutely need an intervention. But if you felt like you need to win last year, you'll probably need one this year.
Nate Bernitz 28:21
By the way, just before we leave the topic of Colorado potato beetles. We did get an email from Heather who just asked how do you prevent potato beetles. She lost a lot of her potato crop last year. And so any other tips besides what we've already talked about for Heather?
Anna Wallingford 28:38
Well, the thing about Colorado potato beetle. And again, I need to open for me this is too cool. So a lot of the times we think about our more horrific past as being invasive and not having good natural controls. It's kind of opposite for Colorado potato beetle. So Colorado potato beetle is named after Colorado because that's where it's native. It's from North America and it didn't become a pest until we brought Irish potato to North America. So this insect was living happily on wild solanaceous crops before we introduce it to what you could probably considered to be a much friendlier host plant. So it grew up and evolved on a plant that has a gnarly set of secondary compounds right so these plants evolved to produce these, these chemicals that are noxious to insects. Colorado potato beetle developed a really fantastic set of tools that help to help it defend itself from these compounds. So it's it's well defended chemically. It's really really hard to control with pesticides because of this, like it can detoxify pesticides really easily. But it has transferred over to these plants that we really, really like. So part of the thinking here is first of all, you're not gonna want to hear this, potato plants can handle quite a bit of defoliation from Colorado potato beetle, probably about 25% loss before you see any impact on the tuber. So you can handle a little bit of damage from Colorado potato beetle. If you have nice big healthy plants with lots of above ground tissue handpick handpicking is not that crazy. So, because these insects are so well defended chemically, they don't have great behavioral responses to defend themselves against predators like birds or other insects. So if you disturb them, they'll just roll over on their backs, the one can, the defense that they do have is that they will, they'll throw up a little bit, they'll throw up a little bit, and they'll produce like this toxin in their in their their saliva. So that's another reason that they don't have a lot of biological controls like their little toxic teddy bears. So you can knock them off the plant, you know, pick them up, throw them in soapy water. Another thing that would be really a terrific thing for you to do is identify the eggs. So we know they're moving into potato plants right now, you can pick off the adult also be able to identify the eggs, they're these these masses of little yellow football shaped egg masses, if you look on the undersides of those potato leaves, you can squish those and, and keeping keeping vigilant can be very helpful there. Knowing that a little bit of full defoliation is not going to hurt you too, too much. Other than that row cover can help. I'm trying to think of other other recommendations, there's really very few biological controls that we recommend. there's a there's a few, actually stinkbug species, some some predatory stinkbugs, I can send you a picture of these predatory stinkbugs hunting the larvae of Colorado potato beetle, but there's not a lot you can do other than trying to keep them off the plants to start with.
Nate Bernitz 31:59
Well, and I should ask about chemical controls in the home garden. And you talked about bio biological controls. There are biological pesticides, they're organic, maybe low impact pesticides, and there are broad spectrum pesticides. I also have heard that Colorado potato beetles are potentially resistant to some pesticides, which is really mind blowing. The the idea that some insects out there could somehow just withstand a pesticide that's supposed to control them. I don't really get that. So maybe you could talk about that. But do you think that there are some chemical tools that might be useful for a gardener like Heather?
Anna Wallingford 32:41
Well, gosh, broad spectrum neurotoxins, you'll definitely knock out a few. But because these animals have evolved to detoxify plant compounds so well. They're also really good at detoxifying a lot of the most commonly used insecticides that are kind of their synthetic versions of plant toxins, really. So you know, there's a few that will work. Okay. As far as biological controls, there's probably not any biological controls that are at the beck and call of home gardeners. I will point out that the BT that we talked about that's effective for caterpillars is not effective for beetles like Colorado potato beetle. There's a few products that I think are a different strain of BT that might have some activity, but I haven't I haven't seen a lot of evidence that they're they're worth sinking that money into. But I will say anything that causes physical damage to the larvae is something to think about. So some soaps can do some some damage. But Gosh, if you're out there spraying soaps or salts or anything like that on a regular basis, which which you would have to do to maintain that, I would say go ahead and pick those off, as long as you're not squeamish.
Nate Bernitz 33:57
I know. Emma and I have both recommended over the years the use of spinosad as a product that can have some efficacy. What's your take on a product like that, that my understanding is that that's a biological product. Is that right?
Anna Wallingford 34:15
Yeah, so Spinoza it's a really interesting product. It's derived from a soil borne microbial species. They actually found it in the soil at or rum distiller, it's got this really strange backstory. So that might explain why there's some tropical themed products out there for spinosad containing products. What I will say about products that are available to the general market is the concentration of spinosad is very low. It's It's It's a fraction of what a commercial grower would be using to provide a control and inorganic system. So these products work best if they're consumed by the animal that's eating it. So they have Eat a little bit of plant material, it makes them sick, they stop eating, if they eat enough that it will make them die. So it's slow acting because they have to eat a lot of that material. And the products that we have at our beck and call are a little bit slower acting because there's such low concentrations in those products.
Nate Bernitz 35:17
Okay, there are definitely a few pasts that we just need to spend a few minutes on. Emma, what's the past that you think we just can't get away with not talking about one that you hear over and over and is real challenging, and we need Anna's expertise on?
Emma E 35:33
Well, I'm hoping you know, we can pick your brain a little bit on flea beetles. Because last year, we heard quite a bit about flea beetle damage on solanaceous crops. And again, I was just talking to a friend over the weekend, who was describing what very much sounded to me like flea beetle damage. So I would love to hear from you, you know what your approach would be to managing flea beetles in the home garden? And if you even really need to be concerned about them?
Anna Wallingford 36:01
Well, gosh, it depends, right. So there's several species of beetles that we call flea beetles. We call them flea beetles because they hop around like fleece. They kind of jump either kind of about the same size. But there's a complex of flea beetles that eats brassica species crucifer. cruciferous plants, we usually refer to that as the crucifer flea beetle complex. There's a couple different species that make up that but they feed on crucifers. And then there's a couple other different groups that will feed on solanaceous crops, there's even some corn flea beetles that can be important commercial pasts. But we might think a little bit about the difference between the complex of species that feed on eggplant and tomato and things like that. So I really think eggplant flea beetle, you see those little shot holes in the eggplant leaves at a plant can handle it right. Let let the baby habits bottle those flea beetles can have as much eggplant as they want. Because the eggplant fruit are going to be fine. When it comes to crucifer flea beetles, a lot of the times were growing those for greens, right? So those little shot holes that are caused by the feeding of those adult beetles are going to be no bueno. Right. So our commercial growers really, really struggle, especially with those growers that we've mentioned before who they have a steady drumbeat of brassica greens, they are always growing them they grow really well even a year round. And I gotta say like, my favorite thing is overwintered. brassica greens like they're delicious. They're sweet. They have like that concentration of sugar from having to deal with that cold stress. So it's, it's really hard not to go grow brassicas year round, because they're awesome year round. But what happens is those beetles, they hop on over to your brassicas, they find them, they eat up the leaves, they cause a shot hole problems, and then they lay their eggs in the soil, those eggs hatch, the larvae will feed on the roots until they're ready to come up again. So if you have a steady drumbeat of brassicas in your yard, you're providing a steady habitat for overlapping generation. So you're just going to build up that population over and over again. So especially in commercial settings, we recommend a summer break, right, so don't grow brassicas during the summer, which for them, that kind of works out they can have a fall crop, they can have an overwintered crop, they can have a spring crop, but during summer when it's the hottest, they can go without that just to have a break, and break that up a little bit and drive that population down. If you're only growing brassicas during one period of the year, like just just one, one planting of whatever you could certainly use row cover. That's one of the the tried and true methods amongst organic commercial growers is to prevent those, as long as you're rotating, and those larvae aren't coming up from the ground where you're growing brassicas last year. Another thing and this again, if you're rotating and you know they're moving into that plot is that light reflected up from the ground actually disorients these insects a little bit. So you might have seen like reflective mulches commercially that reflect light up from the ground, it disorients the insects because they think it's the sun and they're used to going away from the sun, right, the sun's up, they're not on there. So they'll they'll fly away from it. And we found that even some light colored mulches will do something similar so like straw mulch will reflect light up that can that can disorient flea beetles, who are moving in once they're already established, there's really not too much you can do about it. I'm really, really sorry, we're looking into it. I think that spinosa products can help. But if you have a really, really big beat that, you know, a really big flea beetle problem. That's, that's gonna be really hard to control. And I would recommend kind of breaking up that cycle if you have four years of brassica for four seasons of brassicas.
Nate Bernitz 39:49
Am I you wrote an article on flea beetles, I think couple years ago and one of the things I remember from that article is you talked about managing weeds as actually being important, an important tool for dealing with flea beetles. So I guess question for both of you what's going on there are the flea beetles alternatively using the weeds as as a food source? Is it just shelter for them? Because I understand that you can say spray? With something like spinoza like you said, but you may have more flea beetles coming in, presumably from the nearby weeds. So what's going on?
Emma E 40:27
I mean, that's that's the thinking right. And most of us don't want weeds in our gardens anyways. But that weeds might be an alternate food source, depending on what plant family they're in. There aren't a lot of wild brassicas that Well, let me take that back. There are a lot of wild brassicas a lot of these mustard weeds that you might see in the springtime, whether those crossover or not, I don't know. But you know, there's a lot of good reasons for getting leads out of your garden and weeds being a pest reservoir is just one of them.
Nate Bernitz 41:03
Well, I'm glad we got to talk about flea beetles. I did want to bring in a couple questions that from our listeners as well. So asparagus beetle, so Julia, is wondering, one is if it's worth the effort to remove them, or is it important to remove them? Once you're done harvesting your asparagus for the year, you still have that asparagus beetle infestation? Should you worry about it? Is it going to impact you the following year. And then wondering, I think Julie's case as well. She has young asparagus where she's not even harvesting yet and wondering if she needs to manage in that situation, too. And I guess I would just add to Julia's question. Broadly, what are the IPM techniques for dealing with that pest Anna?
Anna Wallingford 41:50
Yeah, so asparagus i think i think different people grow asparagus a little differently, right. So it's this, this underground structure that's putting up shoots early in the spring time. And some people will take the cultural approach, just harvest everything daily, don't let anything touch it so that you're not developing pest populations. Other people will let a few ferns grow up so that you're harvesting spirits as they come up, but you're letting a small portion of those spirits grow up as ferns. Um, so that would be where those asparagus beetles would be the most comfortable and kind of making their home. So if you're one of these people who has a few, a few ferns that that grow up during that time period, that would be where you would target any kind of asparagus beetle, hand removal. Right. So that's that's one approach. It's kind of like a trap cropping approach. Right? So something similar to what Emma was just saying about weeds. You know, if you're creating passions of pests, that could be great if it's keeping it off your main crop, as long as you manage that pest on that trap crop that that preferred that preferred place where they stopped. In reading about that, there's actually two species of asparagus beetles that might be impacting you. One, they're both really beautiful. They're both really like colorful beetles, one is black, and it has three pairs of yellow dots on its back, and the other one is orange. And it has black dots, and they have slightly different life cycles. But in general, these plants can handle a lot of asparagus beetle damage. So in a young planting, like that, I would just wait and hold off and not sweat it until you see a really, really bad outbreak. So we're looking at something like 50 to 75% of those ferns being infested with adult beetles. So after you're done harvesting your asparagus for the spring and you let the ferns grow up, you might go back in and kind of count out of like 20, or 30 ferns, how many of them had beetles on them, if you're getting about 50 to 75% of those ferns having beetles on them. That is a serious population, you might consider taking more seriously the next year, anything lower than that these plants can really handle a lot of damage from these beetles.
Nate Bernitz 44:11
Okay, and I definitely need to ask about horn worms. So the obvious solution with those attacking tomatoes is hand picking. And that's certainly what I've done as a gardener just daily checking and hand picking, which is kind of gross. Like if you squish them, so maybe you're wearing gloves or just kind of picking them off without squishing them and then disposing of them. But I've heard that going out at night with like a black light or something like that can be helpful and that sounds really fun. So I'm interested in trying that. What's your take Anna?
Anna Wallingford 44:49
Yes, apparently they fluoresce. So if you shine them with a black light, and what's really fascinating is that the the moththat lays these eggs is this is Huge night flying moth, right? Like they're really, really, they're fast, they're muscular. They're really unimpressive math. So people who are growing tomatoes within a protected structure, any kind of barrier will prevent that moth from laying its eggs like you can use like hardware cloth. A lot of people who grow high tunnel tomatoes will wall their high tunnels with hardware cloth. And that's enough to keep these big huge moths out. But usually in the middle of the summer, when the caterpillars are quite young, you can go out with that black light, actually, I purchased a blacklight flashlight recently that came with a very long set of tongs for that gross factor. So you could snatch them, and throw them in a bucket of soapy water or whatever, you know, flush that soapy water later. But catching them earlier is better. Because that BT product that we talked about that's effective on caterpillars, that's also effective on hornworms, but only when they're young. So when they're there, when they're first couple of stages, when there may be a couple inches long, they can eat enough of that BT to get them sick and die. So you can get the ones that you missed. Once they get older. Once you start seeing those big honkers with like the big square poops that you might see first, before you see the caterpillar, it's too late to use BT there. And sometimes it might be too late for your plant to they've probably eaten most of it. So going out early. If you can make a party out of it go out at night with your blacklight Why not? We're gonna try it this year.
Nate Bernitz 46:32
Party of one. Okay, and we we should we should talk about kind of the big three of cucurbits. So we've got cucumber beetles, we've got squash bugs, and squash vine borer. And let's start with squash vine borer, because we got a question from James who is trying to prevent the squash borer from infecting his squash plants. So last year, he decided to just rip out the infected plan in the hopes that you'd have better luck this year, he read online that you can't spray pesticides effectively, because the larva burrows straight into the plant making spring pointless. So he's looking for tips on prevention, kind of planting the garden hesitating to devote any limited space to squash without some kind of solution that he's confident will work which I totally understand and also wondering if there's any idea about how to rescue plants that are already infested with squash vine borer, or are they just toast when that happens?
Anna Wallingford 47:37
Well, I would agree with almost everything that you said. So just going back to what squash vine borer is, it's a sesiidae moth, it's a clearway moth, these are actually daytime flying models, right. So a lot of the tools that we usually use to protect plants from nighttime flying moths, like, like barrier. So if you use row cover, if you exclude daytime flying moths using row cover, you're also excluding pollinators, which happens to be really important in this crop system. So cucurbits are insect pollinated plants. So excluding excluding one is a problem for others. What a lot of the approach a lot of people take, though, is that they will cover those plants for as long as they possibly can. So if you put a small transplant out, you give it a good start. by protecting it, they wait as long as they possibly can, until they absolutely have to open that up and allow pollinators to come in. So something to keep in mind is that the first couple of flowers that those squash plants will put off are usually male flowers. So they're just they're just providing the male part of the story. And then that's followed by female flowers, which are producing the fruit that you're after. So you can actually keep that row cover on for quite some time, that plant will grow up big and strong. And even if it goes does get infested by a squash vine borer might be a little bit more capable of handling that damage and producing the fruit for you. So that's one approach. not perfect, but the question that he had about pesticides, that's kind of true, it is very difficult to control this past using pesticides. And it's because the moth will lay that egg, the egg hatches and the larvae pretty much bore in immediately, right, so the only exposure that they have to a pesticide will be that short period of time where that really small larvae bores and so if you're spraying that crop pretty frequently during the flight period of the month, you can use pesticides, but the frequency at which you'd have to spray those pesticides is usually a barrier for most people. So in theory, you could use a BT product, these are mas they're the caterpillars would be affected by a BT product, but you have to have a pretty steady application rate in order to get control for a moth that flies for maybe, I don't know, a month long. You might see activity from this mouth for a month. So if you're out there spraying once or twice a That's not really a great approach.
Nate Bernitz 50:01
I'm wondering for a garden, if you just have a few plants, if like carefully applying some sort of pesticide dust just at the base of the plants could, could that have some efficacy that might not be practical for a large farm where you'd have to dust maybe from the air. But for for a gardener, I'm super concerned, like, I don't want to get dust anywhere near the flowers. But if I was able to just target the base, that's a technique I am considering.
Anna Wallingford r 50:31
Absolutely, if you're willing to be strategic about it, you can apply something to the base of the plant. And not just because the insect tends to, you know, prefer to lay that egg closer to the ground. But the closer to the to the root system, that damage occurs, the more potential it has to impact the overall health of the plant. So yeah, that's absolutely, absolutely an approach that you could you could try. And if you are vigilant enough to just, you know, do a spray to that that area, you can also be vigilant enough to observe the actual damage, which you can, you can tell it's squash vine borer and not some other kind of wilting problem, because there's going to be a hole with what we call frass coming out of it. So entomologists have two different words for insect poop. If it's liquid, it's honeydew. If it's solid, it's frass. In this case, it looks a little bit like sawdust. So if you have a plant that's struggling, even though you're watering it fine. And you examine the base of it and kind of around there and you see a hole with the sawdust material coming out. That's probably a squash vine borer larvae. If you want to be really, really into this, you could stick something sharp and pointy into that hole and dispatch that larvae. I've heard people do that. I don't know how successful it is. I don't know if it's worth your time. But I've heard people trying.
Nate Bernitz 51:52
What's a tool you could use? Like?
Emma E 51:54
I don't know, like a paper like a paperclip? That would be appropriately small. Yeah, piece of wire. I think I've heard of people taking a knife and trying to cut the larvae out.
Anna Wallingford 52:05
Yeah, so what's what's really interesting is that, like you said, there's the Big Three of cucurbit Pass. And depending on what kind of cucurbit you're growing, one is going to be bigger than others. So when you're talking about vining crops like pumpkins, squash vine borer is almost never a problem, because they usually you can lose something that's kind of distal to that route. So far away from that root system, where you're talking about summer squash, and zucchini that had like that big, tight, upright, compact kind of growth pattern, there's more potential for those that that vine board to get close to the root and take out the whole plant versus just like a little tendril that's kind of further away from their root system. So you can just cut out if you want to. But if you're talking about those, those more compact species, that's more of a problems.
Nate Bernitz 52:51
So you might have a different threshold. To go back to a concept you talk like a pumpkin versus summer squash. And then I think butter nuts are kind of resistant. squash vine borer, right.
Anna Wallingford r 53:05
That's what they say, I don't, I think I think the resistance does go back to how much of that plant tissue the plant can lose before it has a negative impact on the fruiting structure. So that's even reflected in the thresholds that we publish for commercial growers. So we do monitor the flight periods of this squash vine borer adult using pheromone beta traps. And so you can go online and see the activity in your area, knowing that that's flying for it speaking a certain period of time.
Nate Bernitz 53:37
And so that could be useful both for timing your row cover, and for timing, potential use of pesticides, but for row cover, like if the worst case scenario there, right, is that the peak of having both male and female flowers aligns perfectly with when squash vine borer are at their highest populations, because then you might be looking at some sort of hand pollination scenario, which you can totally do at a small garden scale, but you'd prefer for insects to do the job for you.
Anna Wallingford 54:09
Yeah, and it really depends on how much you're growing for sure, and how much you're, you know, if you're willing to come in and do some of these really strategic approaches to.
Nate Bernitz 54:19
well, and let's talk about the other two. So squash bugs. I guess the the cool tip that I've heard, and maybe it was from you, Emma, about kind of trapping them overnight. They leave leaving traps for them and then getting them in the morning. What's your take on that and, you know, maybe other techniques you you might employ for those?
Anna Wallingford 54:42
Well, the big difference is squash bug is that unlike other insects that usually have some period of time where they're active at night, this insect is really only active during the day. So it kind of goes to bed at night the way that we do and it does like to hide underneath things. So the board that Emma mentioned If you if you have some of these places where you know, you can reliably go and look underneath it, and and there's a physical removal that's associated with that, too, you can't just create an aggregation. Yeah, they absolutely love to hang out, they like to hang out underneath those things. But you do have to come and dispatch them in the method of your choice.
Nate Bernitz 55:18
Yeah, Emma, do you want to elaborate on that just as far as kind of how you'd go about that, and like, what materials you might use, and then how you might actually dispatch them?
Emma E 55:27
Oh, sure. Happy to, to talk about that. So I don't think you need to get real fancy, I mean, any spare piece of lumber you have laying around, I think that'll work, you know, just a short piece of board that you can put near your plants, because they're not going to wander a long distance away, but you want that board to be set up near your squash plants. And you just put that down on the ground. If all goes well, they're going to crawl underneath it for the night, in the morning. And it's I think, important to get out early in the morning when the temperature is still cool, because at that point, insects are moving slowly. They are cold blooded, I guess, if you will, they're they're not going to be moving real quickly. They're not creating their own body heat. So early in the day, they're sluggish, go out and turn that board upside down. And what I have done is take another board or take a brick and smash those squash bugs that are on the underside of that board. I suppose if you had a big bucket of soapy water to you could maybe just be brushing insects off into that. That feels like more work to me, maybe a little less gross than then squishing all those squash bugs. But either way is going to work. And yeah, I mean, you're not going to get every insect that way, a lot of them are going to find natural things to spend the night under to you know, foliage, maybe some mulch, some other things in the garden, but could help you reduce the population in your garden setting, particularly if you only have a few plants.
Anna Wallingford 57:04
I think I think in this circumstance, having a bucket of soapy water would be key, and being able to identify the bulk of the eggs, because the underside of the leaves, being able to scrape off those. They're like these brown football shaped eggs. They're related egg masses, once they harden. Actually, what happens is that the shell actually hardens as the eggs mature. So if you get those eggs right after they've been laid, you can squish them a couple days after they've been laid. And they're really really hard, you can't squish them. So like run, that kind of rubbing them off with your thumbnail into soapy water is something to do. Being able to recognize those nymphs is really important. So you can recognize them as squash bugs and not necessarily stink bugs. And also being able to recognize that that telltale damage on the fruit where it's kind of like shriveled at the neck. That might be because of squash bug damage.
Nate Bernitz 57:59
And when you say nymph, you're talking about like a juvenile.
Anna Wallingford 58:02
Yeah, to me, they're really quite cute because they've, they've got these little black legs, and they have these kind of gray blue bodies, and they hang out together with their brothers and sisters. But they're they're quite conspicuous to me.
Nate Bernitz 58:15
But one thing you said stuck out, which was you have to look under the leaves, which I think as a gardener, I don't like to do that necessarily. Because like I want to stay on my feet standing straight and just look from above. And for the same reason people might not enjoy weeding, they might not also enjoy kind of bending and contouring their body to be able to look under the leaves. And maybe you can just sort of like peek under by turning the leaf a little bit. But that's such a key takeaway for me. I had also mentioned cucumber beetles, which are a real problem, obviously, for cucumbers. My understanding is not only do they damage your crop, but they can also spread disease.
Anna Wallingford 59:03
So again, situational, I would say the biggest concern about cucumber beetles would be cucumbers. Because of that, as you as you mentioned, they actually transmit a bacteria that causes bacterial wilt. So if you have cucumbers that were doing great before they're being watered, appropriately, like evenly and they're still showing wilt symptoms, there's a possibility that that's cucumber wilt. So you can find some, some varieties of cucumbers that are a little bit more resistant to cucumber wilt. You can do your best to keep cucumber beetles off of cucumbers, but it really only takes one beetle to infect. infect a plant so that that's that's a challenge for other species that cucurbits they can handle quite a bit of cucumber beetle feeding damage. So the squashes, winter squashes and summer squashes as long as you get your plants past the transplant stage. They can usually handle lots and lots of damage. One thing that commercial growers do is they will dip their hole transplants into a slurry of surround or kaylynn clay. So this is a material that's it's an inert clay material that provides this kind of powdery white stuff on the surface of the plant. It's a deterrent for the insect. Either they don't recognize the plant because it's not green. Or they landed the plant and they go, Hey, I don't I don't like this. I don't like this stuff. They're they're grooming themselves and they fly away. So getting that kind of protection when the transplants are really young is key. Once they grow up past that they're big, strong plants, that plant can handle a lot of cucumber beetle damage. Unless, of course, you have a big build up, like you're constantly growing cucurbits, you have a population that's out of control. And you start seeing really big aggregations of the beetles on the fruit at the end of the summer. So that's a situation where you're like, Oh, I really should do something about this next year, if you're seeing beetles actually feeding the fruit freely on the fruit and causing scarring on that fruit tissue.
Nate Bernitz 1:01:07
So to what extent I should ask is chemical control an option for cucumber beetles, for gardeners, and we talked about exclusion earlier, so is something like row cover also a technique you can use here?
Anna Wallingford 1:01:21
Yeah, and row cover is the old standby for most commercial organic growers for cucumber beetle. If they use row cover, and they wait as long as they can until those female flowers show up. Chances are pretty good, that population will never get to a point where they have to worry about cucumber beetle in winter squashes or summer squashes. From a pesticide point of view, that product we were talking about before spinoza that has to be consumed ends up not being a great product for this pest. Ironically, individual beetles don't eat enough of that material for it to do a good job. But but because there are so many of them, they have the potential to do a lot of damage. There's definitely some pyrethroid insecticides that are labeled for organic use. These are broad spectrum neurotoxins that are derived from a plant material that can can put a dent in a beetle population, but it won't take them out entirely. So from from that point of view, there's not a lot of chemical controls.
Nate Bernitz 1:02:21
Yeah, and again, cucumbers are one of these plants that flower and or insect pollinated. And unlike with squash vine borer, where they're going after just sort of the base, and you might be able to do targeted protection. That's a challenge I have with cucumbers is I really am very hesitant to spray anything for anything.
Anna Wallingford 1:02:42
And there's not a lot of good options for spraying in this circumstance. Not with cucumber beetles.
Nate Bernitz 1:02:47
Well, that's good to know me, I thought we could maybe hadn't done Japanese beetles. What's your take on them as far as like, Are they a big problem? And what should gardeners consider for dealing with them?
Emma E 1:03:01
I think it kind of depends, like we've said over and over again that the level of damage Japanese beetles will definitely feed on a number of vegetable crops, particularly beans. If you're a bean grower, you probably have seen this lacy looking foliage before on the bean plant from Japanese beetle feeding. And of course, they will also attack a great number of ornamental plants too, be that annuals perennials, trees and shrubs that are in the landscape. For the ornamentals, it's really just an aesthetic issue in the vegetable garden. If that feeding is extensive, let's say on your bean plants, you might see some reduced fruiting on those plants. For managing the adults, at least in the garden, if somebody is very, very patient and has a lot of time on their hands handpicking those beetles works pretty well. It is an exercise in your reflexes to see how quickly you can you can throw your hand out and catch them. But it works. So catching those putting those in soapy water is going to be a good approach. What I would not use is the pheromone traps that you can find at the hardware stores garden centers that are meant to attract Japanese beetles. There's evidence that suggests if you set those up, you're actually going to be drawing more insects to your garden so might not be the best approach for the home garden. You might be helping your neighbor out by pulling his Japanese beetles over to you. What most people also are focusing on when it comes to this insect today. There's the damage that the adults are doing. And then there's also the damage that the grubs could potentially be doing. Japanese beetles and all the other let's see Asiatic garden beetles, Oriental beetles, these these garden beetles that feed on a variety of plants. They all have white grubs so they're immature for are white grubs that are often growing up underneath turf grass areas so spots where they can be feeding on on grass roots and I want you to see too what else exactly they're feeding on but usually you're you're seeing these in lawn areas, field areas this is this is where they are, you know maturing. And then when they hatch out, they're feeding on just about everything. So some people if they have very large Japanese beetle population in their garden, and they're also seeing signs of damage their turf, say the turfs coming up really easily or there's a lot of animal feeding or damage. Skunks do a lot of damage salons, looking for the the grubs, birds, sometimes well as well. So that's a sign that something you might look at doing some sort of grub control. What I wouldn't do though, and we've gotten this question before, when people are turning over their vegetable garden soil in the spring, they might find some white grubs in the soil, just a few here and there. What I would not do is apply a grub control product in your vegetable garden. It's not labeled for that we get this question all the time. Definitely not something that you're going to want to be doing. But in your lawn area that's potentially appropriate. If there's you know enough feeding damage to actually damage the the plants that are in your lawn actually to damage your lawn. That being said lawns can tolerate a lot of Japanese beetle, Oriental veal feeding as well. So may or may not be something you need to worry about. Usually for me, I am just out there hand picking the adults off of my vegetable plants, certainly off beans and maybe some of the ornamentals, they feel like roses if they're really not letting the flowers come out.
Nate Bernitz 1:06:51
So I think what you're saying is like you can treat for grubs in the lawn to protect the lawn if you want to. But that's not necessarily going to do much to protect your vegetable garden nearby or your trees and shrubs for that matter right there. They're pretty good fliers I think?
Emma E 1:07:10
They are, you can be treating for grubs in your lawn. But if your neighbor isn't, you may not be actually be solving the issue entirely.
Nate Bernitz 1:07:20
They are tough and our Japanese beetles considered an agricultural pest that yes, something that farmers might deal with too.
Anna Wallingford 1:07:29
In some circumstances, yes, Japanese beetles can reach economically threatening populations. A lot of caveats there, right. So a lot of the time, like Emma said, they lay their eggs on grasses, their larvae eat grass roots. So a lot of the times when we see problems with grubs in the soil, it's because you planted something after turf. If you turned some kind of turf or grass crop, you know wheat or something like that into say strawberry. That's when you might have problems with grubs feeding on the roots of that. Another thing that to keep in mind is that there's a lot of really convoluted dynamics when it comes to drought conditions and grubs. So last year, we had a horrible drought. So I would imagine that most scarab beetle populations, these white grubs living under the soil didn't fare very well out in natural Meadows on irrigated places. So those beetles probably were looking for irrigated places like people's lawns or their gardens. So we have been seeing a few more reports this year of people are having growth problems where they maybe didn't have growth problems before because last year's beetles were thirsty and desperate for a place to leave their children behind. So I certainly saw a lot of skunk damage this spring, you'll definitely see that telltale kind of cone shaped hole on the ground that if you think it's cute, it's this it's a skunk snout shaped All right, so we were seeing some unusual things this year. It's really really hard to tell how these consistent drought conditions are going to affect Japanese beetle populations regionally, especially since we're seeing these kind of white grubs in places we didn't expect them from last year's flight.
Emma E 1:09:25
If you're looking to mix things up and try something new in the garden, I would suggest planting ground cherries, also known as husk tomatoes, strawberry tomatoes, or bladder cherries. These are an unusual old fashioned member of the tomato family Solanaceae. And the species typically grown in vegetable gardens is by Salus pruned OSA a tender plant that's native to Central America. Ground cherries bear sweet golden yellow fruits inside of paper yellow brown husks, giving the plant a resemblance to the perennial Chinese lanterns. The flavor is unique, sweet and tangy, and rather unlike any other fruit, though some people liken them to pineapple and tangerines. The trick is harvesting the fruits when they're totally ripe. I find them rather unpleasant when they aren't quite ready. The plants will drop ripe fruits to the ground, so you may have to compete with chipmunks to collect them. So if you want to grow ground cherries, you should treat them like the relative that tomato. sow seeds indoors four to six weeks before the last frost and plant them in the garden once the nighttime temperature is 55 degrees or above, a fertile well drained soil and full sun is ideal. And ground cherry plants get big, at least three feet wide and tall, so give them plenty of room in the garden.
How do you know if an insect is a good guy or bad guy. The vast majority of insects in the environment aren't considered pass. Only a small number of species will attack cultivated plants to the point of limiting yields are seriously impacting aesthetics. In some ways, this makes it easier to identify pest insects. If you can find the insect and know what type of plant it's feeding on, you'll probably be able to figure out the identity of the culprit by researching on university Cooperative Extension websites. And remember, not every insect that choose a hole in a leaf is a bad guy. There are dozens of native insects that might occasionally sample one of your tomatoes or dahlias. But they probably won't do enough damage to seriously injure the plant. Keep in mind that healthy plants are capable of losing about 25% of their foliage without harm. Insect feeding is just part of a plant's life.
Nate Bernitz 1:12:03
Thank you, Anna. Thank you, Emma, this, this has been great. It's going to do it for the 15th episode of the Granite State gardening podcast. I just added them up. And we've gotten to number 15, which is great. We really appreciate everyone listening, everyone sending us questions were able to get get through a few today, which was awesome. So so keep on emailing to GSG.email@example.com one webinar that I'll post the link to in the show notes on garden irrigation, which should be really great. We've talked about that a little bit and a few of our episodes we'll have to do a deeper dive into that at some point. But really appreciate everyone tuning in to another episode of Granite State gardening until next time, keep on growing and managing pests with an IPM approach to Granite State gardeners. Talk to you again soon.
Granite State gardening is a production of the University of New Hampshire Cooperative Extension and equal opportunity educator and Deployer. views expressed on this podcast are not necessarily those of the university's its trustees, or its volunteers. Inclusion or exclusion of commercial products on this podcast does not imply endorsement. The University of New Hampshire US Department of Agriculture and New Hampshire counties cooperate to provide extension programming in the Granite State. Learn more at extension.unh.edu
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