All things trees! (part 2) Pruning and Solving Tree Problems, Plus Frost Cracks, White Oak and Wood Chips [audio]

Forester Greg Jordan joins Emma and Nate for part 2 of a 2-part episode on trees, focusing on pruning and tree problems, with bonus segments on frost cracking and wood chips with white oak as the episode’s featured plant.

white oak

When you see something out of the ordinary with a tree, how do you know if it’s really a problem or just something to shrug off? In part 2 of this 2-part episode on trees, Greg Jordan, Emma Erler and Nate Bernitz talk about pruning a bit to start and then focus most of the episode on a wide array of scenarios and what to do about them (if anything!). If you haven’t listened to part 1 yet, go back and listen to that first. 

  • Featured Question: How to prevent frost cracking? 
  • Featured Plant: White oak (Quercus alba) 
  • Closing Tip: Using Wood Chips 



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Nate Bernitz  0:00  
Welcome to the Granite State gardening podcast, a production of the University of New Hampshire Cooperative Extension. I hope everyone had a wonderful Thanksgiving. We're certainly grateful for all of our listeners and this wonderful community of gardeners we're fortunate to be able to serve. This is part two of a two-part episode we're bringing you on landscape trees. If you didn't listen to part one, I recommend stopping now and going and listening to that episode first before jumping into this one. If you've already listened to part one and are back for part two, I'm going to go out on a limb and assume you enjoyed it and are looking forward to getting into pruning and for most of this episode, tree problems and solutions. Emma also recorded a few interesting special segments on woodchips, white oak and frost cracking. I did want to thank everyone who has completed our listener survey. There's still time to do that if you haven't already. It shouldn't take too long and will help us understand the impact of the podcast and improve it to better meet your needs. As a reminder, everyone who fills it out will be entered in a giveaway for a pair of Felco hand pruners. Find the link to the survey in the show notes, and thanks!

Greetings Granite State gardeners. I'm Nate Bernitz, Public Engagement Manager for UNH Extension, joined by horticulturist and UNH Extension field specialist Emma Erler, as well as Greg Jordan, Rockingham county's Natural Resources Specialist, semantically referred to as the Rockingham County forester. As we launch back into my conversation with Emma and Greg, I'll remind you that we left off part one of this episode with a discussion about watering and fertilizing trees. At the end of the episode, Greg and Emma were actually making a few interesting points about why you might not want to fertilize trees in some situations, like if you want to manage the size of a tree or if your tree is battling a pest like hemlock woolly adelgid, an invasive forest insect pest. Part two picks up with me transitioning the conversation from that to pruning.

From the outset with planting trees, that's where you're more thinking about training trees to whatever extent you can to have the the growth habit and shape that that you're looking for. But I guess at a basic level, Greg, how do you think about the purpose of pruning trees? Is it something that you need to do? Is it something that maybe you shouldn't do? Like, when should homeowners be considering doing pruning? When should they maybe be passing on it even though they're tempted to?

Greg Jordan  2:45  
When you planting a tree, I don't really think that's the time to prune it that first year or two. Like you said, a balled and burlap tree can lose 80 to 90% of its roots in the whole transplanting. It needs all that leaf surface, all that leaf area to make food so it can sort of recover. So immediate pruning, that's not the time to be pruning. However, I think the time to really get pruning trees is early in their life. In the first 10 years, that's the time I think to make a lot of the decisions on pruning trees. It's ideal to prune branches when they're very small. When you make a wound on a tree, we like to say that trees don't heal, they seal. Once you make a wound on a tree, it never goes away. It's not like us, that maybe we get a small cut in a finger and it heals. What the trees do is they compartmentalize those wounds, they never go away. And so it's ideal if you're going to be pruning trees, make those decisions early in the tree's life, so they have small wounds that heal over or seal over very quickly and very full, and you don't have much chance of right in that pocket. So what happens is a lot people plant trees and then they forget about them. The time to prune the trees is, again, when they're young. If you can make some decisions early in the life of the tree, especially about its form, it could be a stronger tree, it's gonna be less prone to storm damage, and it's probably going to have a longer life. So that first decade is the time to be pruning trees.

Nate Bernitz  4:17  
Emma, can you expand on that in terms of selecting and pruning for form? What is your strategy, looking at trees? How do you want it to grow? What are some of the ways you might prune to prevent it from growing in other ways? I guess one example that comes to mind for me, are trees that end up growing with multiple trunks.

Emma Erler  4:41  
No matter what, before you start pruning a tree you should know a little bit about what its natural growth habit should be. Because some trees actually do naturally grow with two or three or four trunks. Or they're produced in the nursery to grow with that habit, so it would be advisable to leave it that way. An example I'm thinking of right now is river birch. A lot of times both in the wild and in cultivation river birch will have two or three or more stems. And when you purchase that plant it's likely that it's going to come with multiple stems. And that's totally fine, that's normal. You can allow the plant to grow in that way. But if you're growing something like an oak, having multiple stems for that plant is not the norm. Nor is that the the horticultural standard. So you might find , you certainly will if you're out in the woods, you'll find oaks with multiple stems. But that's probably because something stressful happened to that tree earlier in its life. Something damaged the main growing point of the stem, that central leader, and it may have split or forked at some point. Or in some cases, you might have had a couple of seeds germinate in roughly the same spot, and you'd have a couple of trees that have come to maturity right next to each other. In general, though, unless you have a tree that typically grows with this multi-stemmed habit, you're going to be better off with just a single trunk. Because when you have multiples, the tree tends to be a little bit more prone to splitting out or storm damage. So for example, if you have a tree that has one main trunk, and then let's say I don't know, five or six feet off the ground, it splits into two trunks or three trunks. As those trunks continue to grow, they're going to put more and more pressure against each other. And over time, it becomes more and more likely that one of those trunks is going to fail in a storm or just from the pressure of those two growing right next to each other. And eventually, typically what happens is one of those breaks out. When that happens, when you have a large tree that had multiple leaders and one of them falls out of the tree, that's usually kind of the kiss of death for that plant overall. The remaining section of it may live for some years yet, maybe even a decade. But that tree is just on a long, slow decline after that happens. So with your young tree, say this is a maple or this is an oak or a beech or what have you, making sure that it just has one main stem growing upwards is going to be critical. This doesn't always happen naturally. The way trees are pruned in the nursery is often to have them look as full as possible so that when you put it into your landscape, you have this miniature looking adult tree. But it's probably going to be necessary to thin out that canopy. It's probably going to be necessary to either remove one of those competing stems or to shorten the length of one or two competing branches that are all trying to grow upright and be the main trunk. There's a lot that goes into pruning correctly. And it's not that it's difficult, it just takes a little bit of understanding of how trees grow and respond to pruning cuts. So that it's not a surprise, when a tree responds to the cut that you've made.

Nate Bernitz  8:27  
Greg, a couple situations people are often running into that are prompting them to want to prune their tree is it growing too close to the house or too close to power lines. So obviously, if you could go back in time, you might plant those trees differently if you were actually the one who planted them. But kind of going back to present day you've got this tree that's too close to the house or a branch that's growing too close to the house or trees competing with the power lines where one one bad storm and you've got a real problem. How do you advise people in those situations?

Greg Jordan  9:03  
That's a tough one. People often love those trees. But like you said the decision wasn't made when it was young to do that pruning. And then you really have not a lot of choices at that point. If it's trees into the powerlines, a utility company - there isn't a lot they can do. They can try to prune around it but often that sort of disfigures the tree and you know it doesn't get to grow in its natural form. So I advise people to make judicious pruning cuts if they need to. It's not ideal for the tree and most situations that arborist walk into are not the ideal situations. So you have to walk in and you have to look at the overall structure of the tree and you have to think about can the tree tolerate this pruning cut? Most of the time they can. It may not seal the wound as thoroughly or as quick as you'd like and you will end up with rot at the stem. But there are really few choices at that point other than to make the decision to prune the tree or remove the tree, if that's the best scenario, and to replant with a species that's just more appropriate for the site.

Nate Bernitz  10:09  
Emma, if you do have to prune, especially some of these more severe cuts where you are cutting a pretty significant branch, ideally, you would have done that back when it was small. But now that you have to do when it is big, is there a time of year to do that and any techniques to reduce stress as much as possible?

Emma E  10:31  
Well, the ideal when you're pruning really any deciduous tree, so anything that's going to lose its leaves in the winter months, is to prune in the late dormant season. So that means late winter, early spring, probably somewhere from February through the end of March or early April, maybe even into the end of April. The ideal is before that trees' buds break, so before you start seeing leaf expansion on that plant. There are a couple of reasons for this. One is that trees in this time period are going to be less susceptible to pathogens. So if there is a particular disease that spread through wounds, you're going to be less likely to spread that disease through pruning when the disease isn't active. A good example, although it might be beyond the scope of this particular talk, is if you have a tree that's in the rose family. This is going to be things like apples or pears or crab apples, that are really susceptible to a bacterial disease called fire blight. That disease is spread once the tree is actively growing. It's actually spread oftentimes from flower to flower by bees that are visiting the plant. But that bacterium is not going to be active if you're pruning in March let's say, so you're probably not going to be spreading it then. Another reason to prune that time of year is that that wound is going to be open for the shortest amount of time possible. Now granted, if this is a very large pruning cut, it's might be open forever. the tree may never totally seal that over. But if it's a smaller cut, as soon as we get into the spring, the tree is going to start rapidly growing again. It's going to be expanding buds, the stems are going to be lengthening, branches are going to be lengthening. So you're going to start getting active sealing of that wound right away in the spring. You don't always get a choice though, of when your tree is going to get pruned. If say you have to have an arborist come in, you're not going to necessarily be able to schedule an arborist to come at the exact ideal time in March or let's say April. And that's okay. For the majority of species, particularly native species that are super cold hardy, they're going to be fine if you prune in the summer, or in the fall or in the winter. But if you have a species that is a little bit more cold sensitive, say it's not native or it's native to southeastern United States, it might be a bit more prone to cold injury, particularly at the site of the pruning cut or pruning wound. So you wouldn't want to prune it in the fall right before you're going into winter. Because you might get more die-back at that wound site as the tree starts to have some active growth or cell division at that site trying to seal it over. You see this in fruit trees quite a bit, if these plants are pruned in the fall or early winter.

Nate Bernitz  13:44  
Some people might be hearing you guys talk about wounds and wondering about the the wound paint that you can actually purchase and apply to these cuts. There are various products out there and they've been used for a long time. What's your take on these products and whether they can actually be helpful or whether there might be unintended consequences, maybe steering you away from them?

Greg Jordan  14:10  
Nate, I'm old enough to remember when they were commonly used. I remember my dad using some wound dressings when he was pruning trees when I was a kid, and it was kind of a thick tar-like wound dressing. There's also paints, and there are some water-based ones as well. And generally, they're just not needed. We've talked about how trees are really good at sealing off wounds, compartmentalizing those, physically and also chemically. It's been shown that using these wound dressings, while it may look nice aesthetically, maybe it looks better to some people, but it may actually inhibit the tree's ability to to seal that wound off. So I typically tell people, avoid those really at all costs. I can think of only one exception. We sort of watch with our breath held as a non-native fungus, possibly something called oak wilt, we're not really sure if it's native or not. But there is a fungus that infects oaks approaching New Hampshire. And if and when that gets here, and you need to prune an oak in the summer, we may recommend using a wound dressing at that point, because that fungus is spread partly by bark beetles. So if there's a wound, they may come to that wound. They'll they'll recognize that tree has been wounded. And they may spread the fungal spores around. That's really the only time that I can think of that I would recommend using a wound dressing. Mostly I try to get people not to prune their oaks in the summer.

Emma E  15:46  
Yeah, I think where the wound dressing thing comes in is that we think if we were to get hurt that it makes sense most times to bandage that wound. That we think we should cover it because that's going to be important for the healing process. But trees are really different and they really don't need that. Like Greg said, it could actually inhibit the sealing process. I never recommend using those products, or really anything else from home, either. I've had people ask me about wrapping wounds with cloth, or in one case, actually putting a face mask or bandana around a wound. And I get it, it's easy to get real attached to trees, and maybe think of them kind of like friends or like people, but they don't need that particular treatment.

Nate Bernitz  16:39  
I brought this up earlier, the person I talked to a few days ago who had topped their trees out of concern for the swaying in the wind. Topping trees is actually pretty common as a practice for various reasons. But a lot of times I hear it's something that is discouraged at the same time. Trees often grow taller than people want them to grow. That could be a fruit tree that you don't want to grow too tall so that you can't harvest it easily, or it could be a tree that's growing up into the power lines, or whatever the case is. Tree topping is pretty common. What would you say about that? And the consequences of a potentially and whether there might be some situations where maybe it is okay?

Greg Jordan  17:33  
I'd probably say no. It's just not a proper pruning cut, at least for trees. I would defer to Emma about maybe in the landscape if topping or a heading cut would it be called if it's ever appropriate? But with trees, topping is just like ruining the growing tip of the branch. It can be indiscriminate. Proper pruning, which you might call a thinning cut is done at a branch collar or at a stem. Topping really isn't that, it's just sort of randomly cutting off the top, it's like severing the trees. It's really considered like mutilating the tree to arborists these days, to really good, qualified, caring arborists. What happens is the tree will respond often with a lot of sprouts around those cuts. But again, we talked about how trees will seal wounds. Well, they seal better at sort of the branch Defense Zone, which is around where the branch collar is, where the swelling with the wood from the stem and the wood from a branch kind of come together, sort of like a deck of cards. The trees are really good at sealing off wounds there. They're not if you just randomly break off a branch at any point. What you end up with is these weakly attached sort of sprouts that can be sort of like parasitic sprouts - they may use more energy than they produce for the tree. Then you end up with a lot of rot. So a situation like a homeowner who wants to protect their house, they may have taken some  structurally sound, limbs o branches and then converted them into weakly-attached branches that have rot around them. So from my perspective as an arborist, there's really no good use for topping. I understand, I've worked with homeowners who had maybe a beautiful champion tree and they didn't want to cut the tree down. So their alternative was topping. And really probably the best decision, although a tough decision, would have been to remove the tree and then plant something more appropriate. But it's a tough decision for homeowners to make.

Emma E  19:35  
I agree with all of that, Greg. And I think one of the things that comes with topping too (because usually toppings are done to control the size of the plant - it's getting too tall), is those weakly-attached sprouts will often quickly catch up to the height of what the tree was before. It's only going to be the matter of a few years or so before you've got a whole bunch of stems now that are really a hazard - that are just as tall as the tree was originally that you cut, so it's not advised. Heading cuts or, we'll call it topping, are useful in the landscape, although not typically on trees. Probably the most tree-like thing I can think of where this would happen fairly regularly might be something like a willow, if you've been going for a very specific horticultural look or ornamental look. And this is often called pollarding, where you're cutting branches back to the same point every single season. What you end up with is these really bizarre-looking, gnarled branches that have these big swollen ends to them that produce new shoots every single season. Not something that I would widely recommend, it's really only something you're going to do if you have just a very specific ornamental aesthetic that you're looking for. And even then you're doing it with with real care. The only other time in landscaping that heading cuts would come in, is if you're shearing a plant. In general, trees do not need to be sheared. In most cases, shrubs don't need to be sheared either, unless you have extremely formal hedges, let's say a boxwood hedge or something around your house.

Greg Jordan  21:23  
Nate, if you do need to reduce the height of a tree or it's growing a little bit too wide, there are some cuts that you can make. There are things called a reduction cut, and it is possible to shorten the branch or shorten the height by cutting back to a bud or another lateral branch that could sort of take over that position for the tree. But again, that's done at a very specific location on the tree and it's not just an indiscriminate, cutting off or topping of the tree. So it is possible to reduce the height of a tree it's just not an easy thing to do and it takes a lot of skill to do it well.

Emma E  22:06  
Are you one of the many people who has noticed vertical cracks in the bark of young trees in winter or spring? Winter weather can be tough on trees, particularly ones with thin bark, such as sycamores, maples, cherries, lindens, and apples. These trees tend to be prone to a disorder called frost cracking. That is the development of vertical cracks in the bark or wood. Frost cracks are often found on trees that are out in the open where sun shines directly on the bark. On sunny days in winter, sunlight can warm the bark in inner wood on the south or west sides of trees. As the sun sets are drops behind clouds, the temperature drops quickly, causing the bark to shrink while the inner wood takes longer to contract. This uneven shrinkage between the bark and inner wood causes the bark to split along with the wood directly beneath it. Unfortunately, once frost cracks have occurred, there isn't much you can do. Sometimes these cracks seal over and trees are fine. But in other situations, the cave fungi and insects may invade and slowly weaken the tree. If you have a damaged tree, the only thing you can really do to prolong its life is by watering during drought. You may also be able to protect newly planted trees with thin bark that don't have any cracks yet, by wrapping their trunks with white reflective vole guards, something you can find at garden supply stores or catalogs. And you may notice if you visit an orchard, that the peach trees, young peach trees have white paint on their trunks, it's the same idea that white color will reflect sunlight and keep that bark from splitting.

Nate Bernitz  24:00  
So for many homeowners, I think like Greg talked about earlier, you plant it and forget it except when you notice something wrong. And all of a sudden a tree that you maybe have taken for granted for a long time as a healthy, beautiful tree. All of a sudden, you're distressed because it's distressed or or you think it might be. And we get a lot of those panicked calls that Cooperative Extension. We're not always able to figure out what's going on just from a phone call or from looking at some pictures, but many times we can. I thought it would be helpful to do some sort of rapid-fire going down some of these issues and talking about whether they maybe look worse than they are, whether they're really posing a threat to the life of the tree or to the structural integrity of the tree, or maybe nothing to be concerned about. And talking about some of the nuance and how homeowners can be a little bit more educated when they're looking at trees in their landscape and deciding whether there's a problem or not. I thought we could we could start by building on a topic that we had already talked about a little bit, or Emma did anyway, with the river birch, multiple stems together. In what situations might you be looking at a tree that has those multiple trunks or multiple central stems, and actually be concerned that there might really be a structural integrity issue that might make that tree a hazard? And what situation might you say that this is totally fine? What do you think, Greg?

Greg Jordan  25:41  
When I look at a tree like that I, I start to assess, and I look at the the branch attachment and the angle of the attachment. If I see U-shaped branch attachments, then I feel pretty good that those are pretty strong attachments of branches to a trunk. If I see V-shaped branch attachments, like you might see on white pine quite a bit, where two branches come together at a very sharp angle, then I start to get a little bit worried about the structural integrity of those trees. And in the forest, that's okay. Like Emma mentioned, that's a situation where you have what's called included bark. So two stems grow together, it's not wood that's joining them its bark. And so as the tree grows and the bark can't attach to each of those two branches, it ends up like a wedge and it pushes those apart. Again, in the forest, no problem. When it's a 100-foot pine over someone's house? That angle of branch attachment starts to worry me a little bit. It's tough to predict if and when those will break, they can last for decades upon decades. But when I see those narrow branch attachments, especially on tall trees like white pine, that's when I get a little bit concerned about the structural integrity of the tree.

Nate Bernitz  26:51  
I feel like we could play this game with like every one of these topics, like arborist or no arborist, right? Should you consider giving an arborist a call and having them actually come and inspect a tree in one of these situations? Greg?

Greg Jordan  27:05  
Absolutely. You definitely give an arborist a call. And there are certain arborists that are track certified - their tree risk assessment qualification. They're trained to look at these hazard trees. But it's really tough for anyone to predict what a tree is going to do when it's got branch attachments like that, it's really tough to know when it's going to break. But there are signs you can certainly see. Sometimes you can physically see a cracking in the stem between those two V-shaped branching attachments. And you know, it's time. A lot of people sometimes will think well, maybe I'll cable those two branches, or many of those branches together. And that is a possibility, cabling tree branches together. Certainly for historic or really important trees, I might consider cabling. But it does come with some drawbacks. Certainly you have to make a big hole in the tree to attach the cables. But it's also sort of is an admission that there's a problem with this tree. Then that tree does break and causes damage. The homeowner may face some some risk of liability from the insurance company, like you knew there was a problem with this tree, but you decided to cable it. So I would definitely rely on the advice of a good arborist who's looked at hundreds of thousands of these trees and can make a prediction about how structurally sound it is and what the likelihood is that it can live through some wind storms or heavy ice loads, for instance.

Nate Bernitz  28:28  
I think another pretty common topic that that we hear from folks are trees where there are holes in the trunks. That could be from birds, from insects, animals, and various causes. Emma, when you hear that, I assume you want to know what kind of tree it is. And depending on the type of tree you might think one way or the other. What are some of the considerations for you when when you hear about holes in a trunk where you might lean one way or the other on whether that's a problem?

Emma E  29:04  
Yeah, one thing you didn't mention was that a lot of times big holes in trees are from pruning cuts that were made to large branches. And that cut or that branch was just far too large for the tree to be able to seal over that wound before decay organisms started to break down that wood in the cut. And over time, as that wood decays, you might end up with a large hole in the tree. You see this pretty often on large sugar maples along the side of the road or even a big oak that had a large limb taken off at some point. A lot of times, I don't know that these trees are major causes for concern, particularly a lot of these deciduous species like that. Something to be aware of, of course is when you have a hole in a tree like that. The tree definitely isn't as structurally sound as a tree without a large hole, because  all of a good chunk of the the wood that's on the inside of that tree, that nonliving tissue, which provides a lot of structure for that plant has now decayed away. We might call it heart rot sometimes on trees, when trees are essentially hollow on the inside. From a health perspective for that tree, it might still be pretty healthy. Because the living bark, which is just on the outermost section of the tree essentially, is fine. And so that tree will keep growing despite having this hollow center, but it isn't going to be as strong. So again, this is a place where you'd probably want to have somebody come in and assess the tree to see whether it poses an immediate risk to your property, to your house, what have you. But if this is a tree that's away from the house quite aways, usually not something I'm going to be too worried about. If you're seeing holes that are created by animals, say a woodpecker has been drilling a hole in a tree, that's probably an indication that there's some serious decay going on there. Or you've got a whole trunk or a whole side of a trunk or entire limb that's completely dead. Because the only time, unless we're talking about yellow-bellied sapsuckers, the only time woodpeckers are drilling into trees is when that tissue is totally dead and it's infested with insects. So at that point, it's time to probably take the tree down, or at least take off some limbs that have completely died. But just a hole alone, probably not cause for panic, particularly if the tree is away from the house. And some of these holes, of course, are great habitat for a lot of wildlife. A lot of birds nest in those holes, and trees, raccoons might take shelter. Yeah, so definitely something to be said for them. And they occur in nature too, of course.

Nate Bernitz  32:07  
What about those sapsuckers? You kind of elevated those as being a case of their own. Why is that?

Emma E  32:14  
Yellow-bellied sapsuckers are a species of woodpecker that actually drills into trees for the sap. So they will eat insects as well. But usually when they're making holes in trees, they're drilling, just these very shallow little wells, and they're lapping up the sap that bleeds out of the trunk. So hence the name sapsucker. Usually, sapsucker damage looks worse than it actually is. Most trees can handle it. And once you know what you're looking for, which is horizontal rows of little holes on the trunk of a tree, you'll know it's a sap sucker, and it's probably nothing to worry about. They tend to attack a variety of trees, oftentimes fruit trees, they tend to love apples and pears. But you can see their damage on on maples and even hemlock sometimes. I've seen people get really concerned when this is happening to their landscape plants, having this woodpecker come in and drill a bunch of holes in the tree. But it's usually not all that problematic for the tree.

Nate Bernitz  33:29  
Greg, we often hear from people who are concerned about borers and their trees, seeing holes and, and thinking that they might be borers. Maybe you can talk a little bit about that, as well as whatever your reaction was, it looked like you were you're ready to respond to Emma there. So yeah, go ahead.

Greg Jordan  33:48  
I was gonna just remind you all that remember, we drill holes in tens of thousands of sugar maples every year and they do fine. Trees can tolerate, a healthy tree can tolerate having a little hole punched in it from time to time. But in terms of the borers, the fact is that trees die. Trees get unhealthy and there's a lot of native insects, borers that will get into trees, especially when they're not healthy. Trees can give off pheromones when they're not well, and [the insects] will lay larvae in there and the larvae will eat wood or decaying wood and emerge  as adults. That is a normal part of a tree's lifecycle. What is problematic is when we have a lot of non-native insects like the emerald ash borer, which is of course as the name suggests, a borer. Our ash trees aren't used to dealing with that. And so the the emerald ash borer is laying larvae in perfectly healthy trees. When we're seeing holes in what would otherwise be perfectly healthy ash trees, then that is cause for concern. We will inspect those trees. Those are easy to detect when they're coming out of the tree because they have a very distinct D-shaped exit hole, because of the shape of the larvaes's head. So if you have a sick and dying tree that has holes in it, that's quite natural. If you have a healthy tree that's starting to show hold boreholes or insect activity, that could be cause for concern.

Nate Bernitz  35:26  
So it sounds like it's pretty specific to tree species and context around the overall health of the tree.

Greg Jordan  35:35  
That's right, and a lot of these borer species are very, if not species specific, general or family specific, so it may be ashes or maples or oaks that these insects target.

Nate Bernitz  35:47  
Another topic, Emma, when people start to notice over time, or maybe just from one year to the next, a thinner canopy - less leaves, less vigorous kind of growth in the top of the tree. That might not be noticeable unless you're paying attention, unless this is a kind of statement tree in the middle of the yard. But if you do notice a thinning canopy, what might that signal to you? Is that a cause for concern, potentially?

Emma E  36:19  
Usually, it is cause for concern. I often think it's indicative of something going on with the root system of the plant. A lot of times, you'll see this on urban trees that have been getting a whole lot of foot traffic over the root systems. It can happen where there's some salt damage, or if there's been construction recently in the area of a tree, where some of its root system may have been severed or damaged in some way. When you really impair the root system of a tree, you start to reduce its capacity to support all of the branches in its canopy. When you start to see this, particularly on a mature tree, where branches seem to be dying out, or there aren't as many leaves coming out, unfortunately, there isn't typically a turning around once that happens. So even if you're doing a lot of watering or you fertilize the tree, usually you don't see a full comeback. It can be kind of the beginning of the end, and that tree is just on a long, slow decline. It might live for, you know, years more, but it's probably never going to be back to its full, healthy, robust state. And honestly, that's that's kind of the case with with any tree that's showing signs of decline for any reason. Usually, once they start to decline, they just keep going downhill. There really isn't anything you can do to totally turn that around. So unfortunately, if you do have a tree in your landscape that does seem to have a thinning canopy with lots of branches dying up high, or just fewer leaves, you're probably going to be looking at replacing it sooner than later.

Nate Bernitz  38:08  
Are there any diseases that might be causing a thinning canopy? Because you had  talked about root issues, and maybe that's a disease? Maybe it's not. So what might you be concerned about specifically?

Emma E  38:22  
Potentially. There are some fungal diseases that can cause issues in the root systems of plants. One is verticillium wilt. You can also see on on elm trees, I'm thinking about an American Elm that's just down the road from me that most likely has Dutch elm disease. This is a vascular wilt. So essentially, if you've got a disease that has infected the vascular system of the plant, usually through the roots, although it could occur through the stem too. And this fungal pathogen is either killing or clogging up the vascular system of that plant so it can't move waters and sugars the way it should. Eventually what happens is that you'll see some die back, typically starting in the canopy, maybe on one side on one branch or so. And this just continues to progress throughout the entire plant. So seeing a branch that's completely wilted and you don't see any signs of mechanical injury, like you don't you don't see any holes there any cuts or injuries to the bark. That could be a sign that there's there's something going on with the vascular system. In that case, too, there's not much you can do to save that plant. I mean, you might keep it alive in the landscape a little bit longer just by trying to keep it as stress free as possible. So irrigating it, especially during dry periods in the summer, but you're not going to bring it back entirely. What I would recommend doing for landscape plants is actually submitting a branch sample of an infected branch and maybe also a healthy looking branch to a plant pathology lab and having a plant health specialist take a look at that branch and determine whether it is a vascular wilt disease. And if it is, you'll want to replace that plant with a species that's not susceptible.

Nate Bernitz  40:26  
I guess one reason why it might actually be useful to know whether there's a disease and if so what the disease is, is even if you can't save the tree that might impact how you think about what to do next, whether it or whether you're replacing that tree and what you might be replacing it with?

Emma E  40:44  
Absolutely, it's definitely going to have an impact on what you replace it with. If if it's a disease issue like that, particularly vascular disease, you're probably not going to put the exact same tree back in again. So if it was a maple, for example, you would likely want to skip maples.

Nate Bernitz  41:02  
So Greg, something that we hear some summers way more than others, it seems like the these questions sometimes come in waves, is about summer early defoliation. In the southwestern part of New Hampshire, I feel like the past couple summers, it's like we've gotten a lot of these types of questions associated with caterpillar damage. The leaves aren't just falling down, you're seeing more frass than leaves coming off the tree. But then other times , early defoliation might be where the tree is just shedding those leaves and might not be an insect or caterpillar. That might be something else like a disease. So when you hear about early defoliation, meaning the tree is losing its leaves before it should be, what are your thoughts there? How might you determine whether there's a problem or whether it's something to shrug off and just hope for a better year next year.

Greg Jordan  41:58  
Oftentimes, it is hoping for a better year next year. Again, it's really species specific and specific to the tree species, but also the insect species. So if I visit a site and I look at a tree and I see it's being defoliated by a caterpillar, say a gypsy moth, or Lymantria dispar, I think we have a new name for it, we're looking for a new common name. I tend not to worry about healthy trees. Healthy trees can tolerate a defoliation. And then they can reflush. It may impact their growth for the year, but as long as that's not a repeated defoliation for two, three or more years in a row, most healthy trees, they'll be just fine. If it's defoliation, and I think it's disease-related, again, that's very species-specific. If I see, like Emma said, an elm that's got flagging and losing leaves on a limb, I worry about Dutch elm disease. If it's July, and there's an oak that's losing its leaves, now I'm starting to think about oak wilt, and that could be very concerning. And so it really depends on the species. There are certainly some trees that are under stress, maybe in a certain year, and they may lose their leaves a little bit earlier than the others. Again, not necessarily a great cause for alarm, and there are certain species like ash that will tend to lose its leaves earlier than a lot of the other species anyways. So you really have to look at the site, you got to look at the species of tree and you got to look at what the causal agent might be. But typically early defoliation is not overly alarming to me.

Nate Bernitz  43:45  
Actually Greg, I'm glad you brought up oaks in your neck of the woods, that eastern part of the state. This summer, we got a lot of questions about oaks losing leaves or rather losing branches with leaves on them and we were seeing what we were calling a bot canker that was going around, these twig pruning insects, squirrels. I mean, there seem to be so many possibilities on what might have been going on. But it was a really interesting phenomenon.

Greg Jordan  44:16  
Yeah, I sometimes call these sick tree calls Nate, and it actually can be kind of difficult sometimes to sleuth out exactly what's going on with trees. I certainly noticed that in my yard. I had at the beginning of the season, I had some oak leaf roller insects, I believe, which is the first time I'd ever seen those and we got some calls about that. I observed some squirrels going up into my oaks and actually apparently gnawing out branches and dropping them down. So I think there's a lot of reasons - we had some other fungal issues with oaks this year. I think because of the drought, the trees are a little bit stressed and a little more susceptible to a lot of native pathogens that are always here. And we did get a lot of oak calls. Again, overall I wasn't very concerned about that. But it can be a little bit unsatisfying to homeowners who call in. It can be really tough to figure out what's going on with these trees sometimes.

Nate Bernitz  45:13  
Maybe you can just clarify what is differentiating for you with oaks between possibility of an oak wilt versus one of these other things? Because it sounds like oak wilt is the one that's going to be concerning.

Greg Jordan  45:25  
That's the one that is very concerning. And I will say to not panic. We don't know of oak wilt in New Hampshire yet, we're just keeping an eye out for it. The the thing to look for with oak wilt is that if your oak tree in July is dropping leaves, that's concerning. If it's dropping leaves rapidly, like you would see in the autumn, and the leaves that are staying, they have a wet look to them, that could be an issue. And that's a vascular issue, like Emma talked about. So the trees really not getting water up and down or water up and nutrients down. So if you're raking oak leaves in July, that's concerning. And I'd want to know about that. And other Extension forces would want to know about that. And the only way to confirm that then is to send it off to a pathology lab.

Nate Bernitz  46:13  
One other thing I picked up on was you mentioned in the context of something like Dutch elm disease, flagging in the canopy. Can you define what you're talking about there? What are some other examples besides Dutch elm that might be associated with with that stop phrase flagging in the canopy?

Greg Jordan  46:33  
I'm gonna try to rely on Emma on this one a little bit, too. But I can answer that partly. If I see what looks to be a relatively healthy canopy, but there is one specific branch or a small number of branches that have turned brown, the leaves have turned brown, they're wilted, and they're still sort of hanging on that branch? That's what to me is the definition of flagging. That's what I'm looking for. So if I see that on an elm tree, I instantly become concerned but Dutch elm disease. That's an early warning sign to let you know that that tree likely has Dutch elm. If you're going to act, that's the time to act, and you have possibly a chance to prune off that branch that's showing those symptoms. You're looking for that sort of unusual canopy die back that there's really no other explanation for. In terms of other species, I can't think of any other species right off the top of my head.

Emma E  47:29  
The one I think of Nate, and I think I already mentioned this, was verticillium. And that attacks a long list of plants particularly, and verticillium is in the soil everywhere. This is a fungal pathogen. But sometimes when trees are already stressed out by some other issue, whether it's salt or compaction, or you name it, they can become susceptible to infection. The maples, for example, are quite susceptible to verticillium wilt. But if you if you do notice this sort of symptom where you just have... and typically what happens is it starts with just a few branches here and there. It's not the entire tree is all of a sudden wilted, it progresses over time, it is probably worth taking a sample and getting it to a lab for diagnosis. In some cases, there might be something you can do to treat, or at least protect trees that are still healthy on your property. For example, you have a really high value old elm tree, American elm, that somehow managed to escape Dutch elm disease and you have another tree go down right next to it. Maybe you look at that treatment for that remaining tree, knowing that this is going to be a very expensive prospect to do that. If you can afford the $20 or whatever it is to have a plant disease accurately diagnosed by a lab, the better off you're going to be in terms of making management decisions,

Nate Bernitz  49:04  
Going back to leaf drop off of trees, some years more than more than others, some trees more than others, we'll sometimes hear about leaf spotting. How would you respond to that?

Greg Jordan  49:17  
I would say that typically when I see leaf spotting, it's typically cosmetic and the trees can usually tolerate that spawning just fine. I think of tar spot on Norway maple, or this year on oak I saw a lot of tubakia, which is a leaf spot.  I think for the most part they show up later in the summer, in the fall. Not always, but that leaf has made a lot of food for the tree and it's really a cosmetic issue. They at least fall off and I think good sanitation is the key there. Rake up those leaves and move them off site away from the tree so the fungal spores won't reinfest the tree. Typically, I don't worry much about leaf spots, although we do get quite a number of calls about them.

Nate Bernitz  50:04  
Emma, how about the the kind of crusty stuff that you'll sometimes find on the trunks and branches of trees? We call that lichen. So what happens if you're seeing that stuff? A lot of times people are very concerned about lichens, and the other one that I kind of put into that same camp, many times they coexist, are mushrooms or other fungi. Maybe shell fungi, or, whatever kind of fungi growing on trees. How concerning is that for you?

Emma E  50:37  
Well, let's start with lichen. Because lichen is not really a concern at all. I think people often confuse it for a fungus, or they might think there's some mold growing on the tree. But lichen is actually a really interesting organism that's super ancient. It's kind of part fungus, part algae. So this is an organism that is actually making its own energy, much like plants with those green algal cells, which is why these plants tend to have a bluish or greenish tinge to them. And it's not feeding on the tree in any way. Lichens will actually grow really on any surface where they have access to sun and moisture. So you can get of course lichen growing on trees, but it also grows on rocks. And it might grow on your wooden fence, or your vinyl siding, what have you. It's just using that tree as a good place to grow. I think sometimes people get concerned about lichen because it tends to be that you get more lichen growing on trees that are already kind of stressed out. I think that's just because there's more sunlight penetrating the branches of those trees. Because the canopy might be thinner, they might not have quite as much foliage. So if you have a tree that's just completely encrusted in lichen, it's probably stressed out from something else. The lichen is not killing that tree or causing its decline. Actually having lichen on a tree is a good sign. Because lichens only grow were in areas where you have very low air pollution. You'd be hard-pressed to find a bunch of lichen growing on a tree growing in the city. But in our more or less pristine landscapes in New Hampshire, where we have good air quality, you should see lichen growing out there. Mushrooms on trees are kind of a different thing altogether. When you see little shelf fungi growing on a tree, or even crust fungi too, that's a sign that there is dead tissue on that tree for some reason or another. The fungi that have or create mushrooms or grow mushrooms tend to be wood decay fungi. They only grow on on wood that is already dead. They would not grow on a live healthy branch and kill that branch. It's just something that is showing up because there is some injury to that tree already. So you'll usually see these on branches that are that are dead or dying. Or you might see them growing on a wound from where a large pruning cut was made. Really nothing to be done about them outside of maybe removing a dead limb or a diseased limb. I guess if you really wanted to you could pluck off a mushroom. Some mushrooms that grow on trees or are edible and really delicious, like a chicken of the woods. Of course, know what you're doing if you're going to forage mushrooms. But the mushroom's not killing the tree. There's something else that happened to that tree that caused decay. Maybe this is another time when you have an arborist come in and take a look at that tree and help you determine whether it is still structurally sound.

Nate Bernitz  54:09  
Greg, how about mushrooms growing near a tree?

Greg Jordan  54:13  
That depends on the species of mushroom. Certainly there are all kinds of mushrooms in the forest soil and soil in general. Some are feeding on trees and others are not. Others are feeding on dead organic matter, decaying organic matter in the soil. Then it becomes a matter of can you identify the fungus. There are certain fungi that are species-specific and if it's growing near the base of a tree, it may very well be the indication of some sort of root rot. But again, to see fungi growing near trees is not at all alarming to me unless I'm able to identify the species and I realize it's Armillaria root rot or something and it could potentially be impacting this tree. But if I see mushrooms around a tree, I'm not concerned at all. Most of the mushrooms are probably feeding on dead and dying organic matter.

Nate Bernitz  55:08  
Greg, sticking with you, something we call a canker, which I would describe as typically kind of a lesion. On the bark, trunk branches, even small twigs can sometimes have these discolored lesions. Sometimes they seem a little sunken or depressed. And if you see that or hear that, how concerned might you be?

Greg Jordan  55:36  
For me typically, I'm a little more concerned if I see cankers on a tree. I think of butternut canker, I think of target cankers that you would see on birches. That's usually a sign that there's some sort of fungi and or fungus infesting that tree.  The cankers are often the signer or the symptom that something's going on with those trees. Those cankers, when that portion of that tree dies because of that fungi, those are no longer conductive parts of the tree. They can't move water up and food down. So often what happens when you get a lot of cankers on the tree, like in butter nut or birch, then is a basically girdling the tree over time. So I do become more concerned when I see a canker on a tree, that there's a major issue with the tree. Most of them are what I would call slow killers, they're not going to rapidly kill a tree, but they weaken it over time. They destroy the conductive material of the tree. Unfortunately, often there's really no cure for a tree that has cankers. It's just a matter of time before the tree succumbs to that fungi or fungus.

Nate Bernitz  56:50  
Emma, another one that we hear pretty often, especially seasonally, is evergreens shedding their needles. Sometimes those needles might be yellow or brown. Is that cause for concern for you?

Emma E  57:04  
Totally depends on the time of year. If evergreen is losing its needles in the springtime, then I am a little bit concerned, potentially. Because it's probably an indication that, or it could be an indication that there's some sort of fungal infection happening within that canopy. I see this a lot with white pine in New Hampshire, where trees seemingly have a thin canopy and drop a lot of needles in the spring. That could be the result of several different fungi. If however, you're noticing needles falling off in the fall, that's definitely much less concerning because that is in fact, normal. Despite the the name evergreen or the term evergreen, needle trees do still drop their their needles eventually. Usually they hold on to them for a couple of years, and then they fall off. Or it depends on the exact species that we're talking about. But they don't stay on there forever. And in terms of the pattern of the needle drop, if the needles are dropping from the interior of a branch, then that is probably totally normal. But if you're seeing needles dropping from the the ends of branches where that new growth is, that's also a cause for concern, or something you might look into more because that that could be pathogen related. But in general, needle drop in the fall is fine as long as it's happening from the interior, not the exterior of that plant.

Nate Bernitz  58:41  
Greg, how about if you see exposed roots above the soil line for a yard tree? Is that normal cause for concern? Why is that even happening?

Greg Jordan  58:53  
It's not abnormal to have roots on the surface. Certain species like maples typically will have more roots that are near the surface. And remember, most of our trees, they don't have roots that are much deeper than two feet below the surface, most don't develop a big taproot. So that's why they're so susceptible to compaction because the roots are typically very close to the surface. And there can be various reasons for that, it could be erosion or compaction. Sometimes there's a restrictive soil layer that retains moisture and roots need oxygen to live. So if there's no oxygen below the surface, then their roots are going to be coming up towards the surface. That might be why you're seeing that. So it could be a compaction issue, it could be a site issue. A few surface roots are normal and not a concern. Lots and lots of roots on the surface is concerning and that tells me there's something going on with that site that's not really appropriate for that tree or the trees not well suited to the site conditions there.

Nate Bernitz  59:56  
Doesn't sound like something you could do a whole lot about though.

Greg Jordan  1:00:00  
There's probably not a lot you can do about that. If you have just a few surface roots, you could put an inch or two of soil over them and maybe put a little grass on there. You certainly don't want to bury them very deeply, because those roots are there because they need oxygen. You could maybe prune a root or two that's at the surface if it's a problem. But generally the trees telling you that there's some site condition there and my roots just can't go any deeper than they are.

Nate Bernitz  1:00:27  
It can really bother people though, especially if it's in a lawn setting and your concern is you're on your riding mower and you don't want to faceplant on your riding mower, tripping over a root.

Greg Jordan  1:00:40  
Absolutely, it's also concerning for the tree as you mow over them and you're mowing the roots. Those are making wounds where decay can then enter the roots and go up to the stem, so it's not good for the tree to be mowing over the roots either.

Emma E  1:00:55  
That could be a good time to put in a ground cover instead underneath the tree so you don't have to mow that area.

Nate Bernitz  1:01:02  
Emma, what about if you're seeing a lot of what we call suckers coming out from the base of a tree?

Emma E  1:01:09  
Some trees are more prone to that than others. But usually that's also a sign of stress of some sort. Could be with the the root system of the plant, could be something going on up higher in the canopy, something is triggering buds to break lower on that stem. That are the trees way of assuring that it's not going to die entirely that it's trying to produce some new stems or some new growth. It's really common on things like crab apples. I should say too, it can also happen when trees are planted too deeply. I think that's often a reason why you see it on ornamentals like crab apples because they were planted too deep, which we already talked about a little while ago. What you can do there, from an aesthetic standpoint, is just prune those off. Or if you know that the main trunk of the tree is in fact in decline, you might leave one of those suckers and have it grow into the new tree. This only works on ornamentals, if you know that that sprout is coming from above a graft. And many times that those sprouts are actually coming from the root stock of that plant. So when you graft, you take two different parts of a plant together: a top piece - a scion, and a rootstock - the bottom piece, and you attach them together. In ornamentals, a lot of times where you get those sprouts is actually from the root stock. So the resulting tree is not going to look like what you planted. You can also get what are called water sprouts in the canopy, too, or sometimes people call them suckers. I usually call suckers growth that's coming from the base of the trunk or from the roots, water sprouts as upright growth that's occurring in the canopy. And again, some trees are just more susceptible to or are more prone to growing water sprouts. Apples yet again, or crab apples are very prone to this sort of strong vigorous upright growth in the canopy. But usually what happens when you get an excessive number of these, it's because the tree was damaged from a storm. So there's some sort of significant injury to the canopy in that way, or from excessive pruning.

Nate Bernitz  1:03:25  
Alright, I got one more for each of you, and then we'll get you out of here. So Greg, how about come late winter, early spring, you notice some significant, what looks like storm damage, like Emma just brought up, to a tree? From snow, ice wind, what have you. In what situations are you going to be really concerned for that tree? And in what situations are you going to feel pretty optimistic that that tree is going to heal up just fine?

Greg Jordan  1:03:53  
Yeah, it's really a matter of the extent of damage. Certainly, again, if we go back to when the tree was young, and it was pruned well, and it's it's got a strong architecture and strong limbs, it's gonna be able to weather those storms a little bit better. But if it is damaged in a storm, certainly you have to look at what's broken. If it's more than 50% of the crown, then I really have very little hope that the tree is going to recover. Biologically it may live for many years, as we've talked about, but ascetically it's lost that appeal. So I look at the extent of damage. A few minor limbs broken, no problem, just go ahead and prune those off. It's important to do nice, clean pruning cuts. If you have limbs that break and they have ragged sort of edges and not a smooth cut, those don't heal or I should say seal quite as well. So you want to do a nice clean pruning cut. Otherwise they act like infection courts where fungi and insects are attracted to. Minor damage, 10% 20% crown damage, typically can be pruned out Get above that, especially over 50% like we'll see a nice storms and things, and it's probably time to remove and replace the tree.

Nate Bernitz  1:05:09  
Alright Emma, one that we get some springs more than others, when flowering trees like dogwoods or cherries, or whatever it is. If you see no blooms at all, or just diminished blooms on those flowering ornamentals, what are your thoughts there?

Emma E  1:05:31  
I would probably guess that it's something weather-climate related, when you have reduced bloom on a tree in the spring. In particular, with plants that aren't native to New Hampshire, and this is a lot of those flowering trees that we have in the landscape, they might not be perfectly adapted to our winter conditions. A lot of times, what happens is that these trees start to wake up, if you will, or will start to grow in the spring before winter is really over. They basically evolved to have a shorter winter period. So they will come out of dormancy earlier than they should in our climate. Once they come out of that dormant period and start to grow; once their buds start to expand and their flower buds, start to expand or maybe open a little bit, they're really susceptible to cold temperatures. If we get a late freeze, or just have extended cold in the spring, after they've started to break that dormant period, then a lot of times you'll just lose the flower buds entirely. This happens a lot in stone fruits, for example. Why some years we we don't have any peaches in New Hampshire, because we get that late freeze. This is not something that you would typically see on a native plant, though. So we have a number of native cherries. You don't see that on those plants, because they have evolved to have a long enough dormant period. They will stay dormant or it takes more cold in order for them to break their dormancy. So you just don't see it. But if you have something in your landscape that's native to Europe or to Asia, it's more likely that you're going to lose that bloom in the spring, particularly if you're pushing the envelope in terms of zone hardiness. So if you live in Zone, let's say five, and you're you're trying to push it with a plant that's really happier in Zone six, it's going to be more likely that you lose your bloom.

Nate Bernitz  1:07:41  
So Greg, you're a county forester, you're also an arborist for homeowners. When should they consider hiring an arborist and how might they find a qualified arborist?

Greg Jordan  1:07:54  
When you decide a tree needs to be pruned or a tree needs to be removed, or you want to plant a new tree, that's a time to find an arborist. There are a lot of great arborists in New Hampshire. There are two certifying organizations. We don't license arborists in the state like we might license a forester for instance, or a surveyor or an engineer for instance, but there's the New Hampshire Arborist Association and they do maintain a list of certified arborists. The International Society of Arboriculture, they also maintain a list of certified arborists that you can search and find one that's that's close to you in the state. And then sometimes too we have folks that have other issues with trees where they need a consultant and they may have a legal issue with the tree, maybe a dispute with a property abutter. Then there are consulting arborists and you can find the association of consulting arborists online They're more able to help with diagnosing pest issues and helping with legal issues. So there's really a variety of professionals in the state. And they're easy to find online.

Nate Bernitz  1:08:57  
Thanks, Greg. We really appreciate your time today. This is this has been great.

Greg Jordan  1:09:01  
Yeah, thank you guys both. I hope you find something usable from this.

Nate Bernitz  1:09:05  
I think just about everyone will. Now that Greg's left the studio, what's your feature plant for this episode Emma?

Emma E  1:09:20  
The featured plant this episode is one of the first trees I recommend when someone's looking for a tree with excellent drought tolerance. It's white oak, Quercus alba. White Oak is native to New Hampshire, and it typically grows on dry upland slopes and ledges, as well as lowland valleys and ravines though it will grow much faster in rich, moist, acidic, well drained, loams and full sun. White oak will also perform well in dry or shallow in rocky soils. White oak is a good choice for larger landscapes, because it is a tree that can grow 50 to 80 feet tall and wide. Its only drawback is that it's slow growing, though it can live for hundreds of years. Perhaps most importantly though, white oak is an important food source for many dozens of native insects, birds and mammals. If you're interested in ecological landscaping, you have to have at least one white oak on your property.

Nate Bernitz  1:10:19  
I'm really glad you featured white oak, Emma. It's an amazing and unheralded tree some people look at it as a nuisance to clean up after without necessarily thinking about what important trees they really are. I also understand you have a closing tip for this episode.

Emma E  1:10:33  
Having a tree taken down on your property? Make sure you ask the arborist to leave the woodchips behind. Fresh wood chips, whether from soft or hardwood trees, are incredibly useful as mulch. I've had great success using them to mulch around trees and shrubs in my own landscape. Or they can be used to mulch pathways through flower or vegetable beds. As woodchips are breaking down. They can temporarily tie up nitrogen, but this is seldom an issue around woody plants. If for some reason you're using woodchips to mulch perennials, and are really concerned about nutrient deficiency, simply applying some slow-release nitrogen fertilizer at the proper rate around plants will solve this issue. Make sure you put those wood chips to work.

Nate Bernitz  1:11:18  
I love that you featured woodchips. I've been putting them to work myself after having a couple  of arborists drop off chips from other jobs at my home. I love using them not only as mulch like you described, but also for pathways and for smothering weeds as site preparation for creating new gardens. Well, we're at the end of this two part episode on landscape trees. I want to again thank Greg Jordan for coming on with us. In the show notes I'll include a link to where you can contact your county forester if you live in New Hampshire. And of course, thanks to Emma as always. I want to also share some gratitude with our executive producer Dave Kellam, who truly makes us sound better than we do in real life. Obviously I'm in a thankful mood coming off a great Thanksgiving with family and friends and I hope you had a great Thanksgiving too. Until next time, go ahead and scout your trees for the issues we talked about today. And sharpen those pruners and loppers for late winter pruning. Granite State gardeners, we'll talk with you again soon.

Granite State Gardening is a production of University of New Hampshire Cooperative Extension an equal opportunity educator and employer. 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

Transcribed by Transcript edited by Rebecca Dube.



Nate Bernitz
Public Engagement Program Manager
Extension Program Mgr
Phone: 603-351-3831
Office: Cooperative Extension, Taylor Hall, Durham, NH 03824

Gregory Jordan
Forestry Field Specialist
Assoc Field Specialist
Phone: (603)679-5616
Office: Cooperative Extension, Taylor Hall, Durham, NH 03824

Emma Erler
Landscape and Greenhouse Field Specialist
Instructor Field Specialist
Phone: 603-641-6060
Office: Cooperative Extension, Taylor Hall, Durham, NH 03824