Talking Trees with Davey Tree

Zombie Trees - When Good Trees Go Bad

October 28, 2021 The Davey Tree Expert Company Season 1 Episode 42
Talking Trees with Davey Tree
Zombie Trees - When Good Trees Go Bad
Show Notes Transcript

Brian Sieber from Davey's Cincinnati office  talks about the dreaded zombie trees! What are they, what kind of damage can they cause and how can you cure and avoid them?

In this episode we cover:

  • What are zombie trees (1:00)
  • Root problems (2:33)
  • Construction damage (3:04)
  • Poor tree architecture (3:40)
  • Can a zombie tree be cured? (4:19)
  • Free consultations (5:34)
  • Satisfaction of helping a tree (6:01)
  • Cabling (7:22)
  • How Brian started his job (8:15)
  • Fertilizing (9:06)
  • Raking leaves (10:44)
  • Hemlock woolly adelgid (11:27)
  • Weather in Cincinnati this year (12:26) 
  • Watering your tree (13:58)
  • Good growing and low maintenance trees for your yard (15:58)
  • How to avoid zombie trees (18:52)

To find your local Davey office, check out our find a local office page to search by zip code.

To learn more about zombie trees, watch our Zombie Trees Talking Trees Live video.

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Doug Oster: Welcome to the Davey Tree Expert Company's podcast Talking Trees. I'm your host, Doug Oster. Each episode showcases one of David's certified arborists sharing advice with everyone about caring for your trees and landscapes. We'll talk about everything from introduced pests, seasonal tree care, deer damage, how to make your trees thrive, and much, much more. Tune in every Thursday to learn more because here at the Talking Trees Podcast we know trees are the answer.

I'm joined this week by Brian Sieber. He is a district manager for the Davey Tree Expert Company in Cincinnati, Ohio. I've spent a little time down in Cincinnati myself being a Clevelander. Today we're talking all about zombie trees, Brian. It's Halloween and zombies tree sounds scary, but it doesn't have much to do with Halloween. Does it?

Brian Sieber: No, not a bit. I am totally ready to embrace the holiday season. I am looking forward to our discussion a little bit on zombie trees. Zombie trees really just our reference to trees that look kind of normal, but have some underlying issues that can be hazardous or dangerous.

Doug: When I'm thinking about a zombie tree and I'm in my own landscape, what should I be looking for? What are the symptoms of a zombie tree?

Brian: Well, that's part of the reason why there's zombie trees. For a lot of people to the naked eye, it just looks like a normal tree. Nothing completely out of the ordinary but upon closer analysis, there might be a series of things that you look for that will shed light on some of the dangers that those trees might have. We could probably get into some of those. They could be something as simple as dead wood or cracks or splits, but there's many other things that could be there.

Doug: Basically, if I'm worried about a tree, especially after a storm and I look up and I realize because from hosting this podcast, one thing I've learned is look up, look at those trees. If I do start to look up and I see dead wood and cracks, I should call my Davey Tree Expert, right?

Brian: Absolutely. You should have an arborist on site regardless after the summer storm season to really give a careful look at your trees and make sure there's not any real underlying issues. We are currently into the fall season. Sometimes you're able to get a little better view of those trees and really what some of those issues might be.

Doug: If I'm looking at a tree, is there a possibility that there could be root problems too in one of these so-called zombie trees?

Brian: Well, sure. It's good to take a look like you said earlier at the tops of the trees to see how the trees are growing and how they're doing. Sometimes when you look at the tops of the trees, it gives you a better underlying understanding of what the roots are. The roots are all underneath the soil so you don't really have a good visual assessment of those most of the time, but the tree will always show you a little bit of signs, maybe some symptoms of what might be occurring.

Doug: One thing I've learned from doing the podcast is it's important to look at those trees if there's been any construction at the home or in this area that your trees are where big trucks or something could be running over those roots, right?

Brian: Oh yes, absolutely. If you've had construction on a property, you're looking at stuff along the lines of compacted soil, damages to some of the buttressing roots going up to the tree. A lot of that stuff gets mashed into the tree surface. It doesn't always readily stick out whenever you just walk by or glance at a tree from a distance.

Doug: Now before we came on, we talked about something you said called poor tree architecture. What does that mean if I'm looking at a tree?

Brian: If you were looking at a tree, you want a tree to have a little bit of room to expand, room to grow, a little bit of breathability. When we look at trees from an arborist point of view, I'm looking for good brand scaffolding. You'll have a branch that staggered with another branch slightly above it. It gives each branch good room to grow and you look for good branch structure within that tree because poor branch structure in a tree will often lead to splits or cracks or damages to a tree as they grow, expand and gather new weight.

Doug: Tell me a little bit about some of the things that you do and I know it's dependent on each situation being unique, but what are some of the things that you can do for a zombie tree depending on what's happening with the tree?

Brian: Well, I think you and I both know step number one, get a good set of eyes on the tree. Have your local arborists, whoever it is, come out there and get a regular visual assessment. I'm a big preacher that when it comes to having people out on the property, do it multiple times during the season. Do it once in the springtime to see how trees are recovering from the harsh winters. Also, another time in the fall, when the leaves are falling off the tree you get a little bit better idea of big, large dead limb stuff like that that might be in place.

Step number one for me is always go through and do a good assessment on the tree. Step number two is looking at having your tree pruned, sending an arborist up in the tree. Have them assess the canopy when they're up there. They can identify and remove dead limbs when they're up there, they can identify the branch junctions, how those branches combine with each other, and see if the mechanics of the tree are all in good place.

Doug: Well, one thing I always want to remind people is that if you do call the Davey Tree Expert Company, a certified arborist comes out for free, right?

Brian: Absolutely. We do free assessments on the tree. You'll have an arborist on site. There'll be able to go through and give you a great opinion on the trees' current growing condition, perhaps its exposure to the elements and the hazards that might be associated with that tree.

Doug: One thing I like to ask arborists here and there is what is it like when you can take a look at a tree and say, we do identify as the so-called zombie tree, but then whatever it is that needs to be done, you can tell that homeowner, "Hey, you're in luck. I can fix this." Tell me a little bit about that relationship with the homeowner.

Brian: It's always nice to meet the clients and meet people that are also equally as enthusiastic about the landscape as somebody like you and me. When they're onsite, a lot of the times they'll call you up and be like, "Brian, I've got this tree, It's overhanging my house. I'm really concerned about this deadwood or these branches as they're intruding," or anything else like that? "I love the tree, but I don't want to take it down. Is there any middle ground for that?" There is a lot of the times. A lot of the times, it might be simply removing part of a branch.

It might be cabling the tree back to eliminate hazardous, poor branch structure. There could be a multitude of options there. There's always a great relief to clients and people that are passionate about their trees that, "I was worried when you first got here that all we'd be doing is cutting it down," and it's not the case.

Doug: Tell me a little bit about cabling. How is that used in working with those trees? I hear arborists talk a lot about it.

Brian: Cabling really gets implemented a lot in our industry. Whenever you have an established structural defect in a tree that can't be reconciled by simply just pruning the branches back for either structural reasons or aesthetical reasons, cabling might be a good option for them. What cabling does is it puts a support system in at the top of the flawed branches and allows those branches not to overexert themselves in either direction so that if there's a break or a split in the bark, that the tree branches can't separate out enough in order to make that split worse.

Doug: Let's get into a little bit about why this job's right for you. How did you find your way to doing this type of work?

Brian: For me, I grew up in the rural, what is now probably the suburbs of Cincinnati. The house that I grew up in butted up against 45 acres with a forest. For all my life, that's all I've done, play in the forest, play in the trees, and have a good time outdoors. This is just a natural flow through for me on my love on the environment. In my industry and for the years I've been with the company which I think this year is probably 20 or 21 in, I've done a little bit of everything. In the green industry, there's tons of options on ways to get involved. I've enjoyed every bit of it.

Doug: This time of the year, we're doing a lot of planting in the east. Are we still fertilizing or is that window closed?

Brian: Absolutely we'll be fertilizing on our end through October and November. Seasonally, you would look at depending on what your temperatures are and how accessible the areas are on how good that'll be but never bad to put fertilizer to the trees in a residential environment.

Doug: Tell me a little bit about how you fertilize a big giant tree. I just thinking off the top of my head that needs a lot of fertilizer, right?

Brian: It does. At Davey, we use a product called Arborgreen. It's a non-soluble powder and we mix it with water and we use water injection system where we pump it into the soil layer in almost a grid pattern underneath the tree canopy. That way it evenly disperses underneath the ground in that root zone area where we really want to get the most benefit out of our roots.

Doug: How do I know if my tree needs fertilized or do trees just need to be fertilized?

Brian: In a residential environment, a lot of the times we strip away a lot of the healthy things that trees might want. We rake up our leaves. We have manicured lawns. There's no decomposition. None of that stuff is really there. In a forested environment, you might not worry about any of that stuff. It’s there all the time. In residential environments, it's completely different. If your trees are in a residential area, it will always benefit from having fertilizer on an annual basis without any problem.

Doug: Did a certified arborist, just tell me, I don't have to rake up my leaves. Please say, yes.


Brian: I cheat on mine. What I do is I go through and I'll mulch mine out with the mower at least a couple of times during the year. Then there comes a point in time in the year where I won't do that anymore and I'll rake them up and get rid of them. It's your area that will really dictate that. My neighborhood if I left all the leaves there, they would kick me out of my neighborhood.

Doug: Well, I live in the woods. I'm not raking up my leaves except on the driveway.

Brian: You blow them off the driveway and into the woods and be done with it at that point.

Doug: They'll feed my hemlocks. I've got a whole line of hemlocks that have hemlock woolly adelgid. Down in Cincinnati area is hemlock woolly adelgid become a problem too like we have here in Pittsburgh.

Brian: It's starting too, yes. That's regionally for both me and you. It's starting to become a lot more common, unfortunately.

Doug: I've been battling it. Luckily for most of the time, it's been in the bottom of the trees. I'm just with my home sprayer covering them with horticultural oil. What happens if they start to work their way up the tree? I can't get to it. What are you guys thinking as far as the treatment?

Brian: At that point in time, you would have to look at an integrated pest management program, something where you do a multitude of approaches. You increase the health and the vigor of the plant. You go through and you still do your dormant oil treatments when you need to, but you might use something that's a little more prescribed to tackle on adelgid issues on hemlocks.

Doug: Tell me a little bit about your season this year in the Cincinnati area. How was it for you?

Brian: Spring, we had a pretty normal spring for us at least about a month, month and a half here. Summer was hot, I'm not going to lie. I don't know about you or the rest of the country, but summer here was hot. We had some alright rainfall from parts of it, but for the most part, August was a dry, dry month for us.

Doug: What does that mean as an arborist when you have a drought-like summer?

Brian: Usually, that means for me, and it means for a lot of us that we look at-- Like we talked about earlier, we really try to perpetuate a lot of repetitive onsite visits. I know I do out of this office with a lot of our clients. I try to get back all out on a lot of properties on a regular basis and see how some of the stress trees have dealt with the summer heat. A lot of the times, your smaller ornamental trees might get a little burn up for the leaves. That ultimately, can affect them the next growing season.

It's always good as we've already talked about to really promote the use of fertilization, regular irrigation on trees, if at all possible. It'll definitely make their job easier in the long run.

Doug: That's where I wanted to go, irrigation. Again, our topic is zombie trees and there could be young trees out there that have stressed over this dry period. We had the same thing up here in Pittsburgh. Talk a little bit about the right way to water a tree. Then how long do we water that tree into the season if rain is scarce?

Brian: Let's say, I'm working with a brand new tree, something that let's say, Doug, you went out there last year or last fall. You say, "I'm going put a new maple tree in my front yard." Typically, what I tell people to do is I tell them to work on irrigating that tree two to three times a week, mimic rainfall as much as possible. Trees like relatively speaking about an inch worth the rainfall a week if they can get away with it. Stress trees might like a couple of inches worth of rainfall during the week to maintain that good soil moisture that's there.

That's really what you want to want, is you really want to maintain a certain amount of soil moisture in order for those tree leaves to grow, ease their way through soil, and pull the nutrients out of the soil. Here, I tell people to start irrigating sometime in May and sometime in September or October when the temperatures go down. A lot of people ask me though, they say, "Brian, what's a good way to gauge the soil moisture?" There's a couple of different tests. I always found the easiest one for people that are really specific into it was really just to go out and get yourself a moisture meter or something like that.

Buy them. They're not overly pricey on Amazon, stick them in the ground, wait 30 minutes. They'll tell you if the soil composition is good for you or not. That's really the most accurate way to do it, but you can get down and just feel the soil, feel how saturated it is. If you clump it up into a nice mud ball and the water squeezes out, it's about perfect at that point.

Doug: It's funny because we've had this dry summer and we got some rain, but I went in there to do some ball planting actually. I couldn’t see right off the bat that rain didn't do what I thought it did. That's great advice to get down into the soil and use these 10 indicators that we have these fingers to figure out if there's water in there. Now, Brian, I'm going to put you on the spot. Give me a couple of trees that aren't used as much as you think they should be in the landscape. Now I always preface this with I know that the site is everything, right tree, right place. See I've learned.

Brian: You're good with me.

Doug: Do you have a couple of trees in your head that you're thinking, “First off, these are not going to end up to be zombie trees?” What's on your list?

Brian: From being in the industry for 20 years at this point in time, especially in our end of the work, I always look for trees that are good growing and have a low maintenance issue to them. Let's face it, if you’re were out there climbing trees all day or you’re installing trees all day, the last thing you want to do is come home and have to work on a tree. That being said, every year I have different trees I like but for the most part, I've had a pretty solid staple of Zelkova is one that I really am fond of. They grow at a pretty decent rate, have a base-like shape to them.

They're a good residential tree. They're medium-sized, so they don't get overly tall and they maintain a good foliage. They look nice in fall.

Doug: That's one I haven't heard an Arborist talk about before. That tree just gets on your list because of all these years of planting, planting, planting, and here's one that doesn't need a lot, but looks good.

Brian: It looks absolutely gorgeous. They maintain a nice full canopy at a relatively low part in the yard. You don't have to worry about some gigantic hickory tree or gigantic elm tree taking over the whole property. This one maintains a nice low foliage. It grows at a really nice rate, good in a residential environment. It doesn't stress out as much due to the heat or the pollution or the salt content as much. They do really good. I like them.

Doug: Anything else you can think of that you'd like to recommend?

Brian: There're some staples out there that people will always tell you are really nice. We get a lot of people that plant maples that are pretty hardy around here. I would love to say that we have more hemlocks here for you, but the soil content just isn't as good for hemlocks. Overall, any tree is better than none. Oh, one I've really liked over the years is a sour gum or a tupelo tree is a really colored, also a really good-looking tree.

Doug: That's the one that has really good fall color. Am I thinking of the same one?

Brian: Yes. They get a dark red, almost an orange color to them. Small little berry is a fruit that you can just barely notice. They grow upright. They're really solid trees if you're looking for a long-term shady type tree.

Doug: Let's finish it off by just telling people some of the best ways just to avoid these so-called zombie trees that we might have to deal with. We've talked about, of course, having an arborist visit, so important. It's something that I've learned again over the year of hosting this, have somebody come over. Now at my own landscape, four acres of oak trees, I'm keeping the Davey Tree Expert Company in business.

Brian: [laughs] With any of that stuff, it's an ounce of prevention. It goes a long way. Your regular inspections are good and they'll help identify the problems, but you got to take the next step. When the arborist is there and takes you out there and says, “Doug, what your plants need are fertilization. You need to do some regular pruning maintenance on these. Let's thin out the canopies a little bit. Let's give rid of some of these dead limbs so that they don't cause cavities later on,” take that step and do that. If you don't want the zombie trees, getting those trees pruned and doing just a little bit of preventative maintenance on them goes a long way for their longevity. I think you and I both know in order to get big oak trees like you have all over your property, you got to do a little bit in order to make them last that long.

Doug: Great advice, Brian. Thanks again for your time and it's Halloween, but we're not going to celebrate zombie trees, that's for sure.

Brian: You're definitely not going to celebrate zombie trees. Thanks for having me, Doug. I appreciate it.

Doug: Thanks again. I don't know about you, but when I think of zombie trees, that scene of those scary apple trees in the Wizard of Oz comes to mind. Now tune in every Thursday to the Talking Trees Podcast from the Davey Tree Expert Company. I'm your host Doug Oster. Do me a favor, subscribe to the podcast. We're having fun and we're learning too. For next week's show, we'll go over a comprehensive winter checklist for your trees to get ready for the change in the seasons. As always, we like to remind you on the Talking Trees Podcast, trees are the answer.


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