How to Make Flowering Trees Thrive + an Arborist's Favorites

Mike Holleran from Davey's Wilmington, Delaware, office discusses how to make spring-flowering trees thrive, what diseases threaten them and some of his favorites. 

In this episode we cover:  

• Flowering tree diseases (:45) 
• Disease resilience (2:39)
• Treating flowering tree diseases (4:00)
• Fertilizing (5:20)
• Inspection from an arborist (8:27)
• Pruning (11:51)
• Mike's favorite spring-flowering plants (15:21)
  • Witch hazel (15:37)
  • Serviceberry (17:41)
  • Redwood and dogwood (20:35)
  • Okame cherry (26:04)

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

To learn more about caring for flowering trees, read our blogs, How To Care for Flowering Trees & Shrubs Year Round and Why You Should Fertilize Flowering Trees.

To learn more about when your flowering tree will bloom, read out blog, When Do Flowering Trees Bloom in Spring, Including Fruit Trees. 

Connect with Davey Tree on social media:
Twitter: @DaveyTree
Facebook: @DaveyTree
Instagram: @daveytree
YouTube: The Davey Tree Expert Company
LinkedIn: The Davey Tree Expert Company 

Connect with Doug Oster at www.dougoster.com. 

Have topics you'd like us to cover on the podcast? Email us at podcasts@davey.com. We want to hear from you!

Transcript

Doug Oster: Welcome to the Davey Tree Expert Company's podcast, Talking Trees. I'm your host, Doug Oster. Each week, our expert arborists share advice on seasonal tree care, how to make your trees thrive, arborists' favorite trees, 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 again this week by Mike Holleran. He's an assistant district manager in the Wilmington-Brandywine-Delaware Davey Tree office. We have a really good one planned for you today. It's all about making those spring-flowering trees thrive. Nothing pleases me more, Mike, than asking an arborist about their favorite trees. Let's start with making those spring-flowering trees thrive. Being selfish, I'm going to start right with my crab apple, okay?

Mike Holleran: Sure.

Doug: My crab apple, it's been there as long as we've been living here, 28 years, and it blooms every spring. It looks great, but then about three-quarters of the way through the summer, the leaves start to turn yellow and drop. What's going on?

Mike: Yes, a lot of foliar fungal issues with those trees. It's not just crab apple. There's a ton of them out there. We get powdery mildew on dogwoods and apple scab and rust diseases, and things like that can defoliate a plant. Fortunately, very uncommon for that to be fatal. It certainly makes the tree look a little scary. It's startling when you're not used to what to expect. If you can wrap your head around the fact that your tree is going to lose all its leaves, most of the time, they will push through it. It'll push a new set of leaves, and you'll be good to go.

Doug: Do you think I'm risking something here? This is a tree that I love. I tell the story all the time on the podcast that a pine tree behind it fell on it and the house. The team from Davey came, and they wanted to take that flowering crab out. I was like, "Oh, man, I just love that thing." Of course, they're about the only ones that would understand this. It's like, I love that tree.

Could you prune it in such a way that, in a few years, it would look okay? The guy was looking at it. He's like, "Yes, let's try it. Why not?" He said, "It's going to look funny," and it did look funny for a couple of years. Now, you wouldn't know that a pine was on it. Again, I love this tree, but it does completely defoliate by the end of the season almost every year. I don't want to risk the tree.

Mike: Trees are resilient. Like you said, with the pine and the tree's ability to react to what's going on within its system and the things around it, they're very resilient. Don't get me wrong. It takes energy for that tree to manage that disease. Especially if it defoliates, it takes a whole boatload of stored energy that that tree has to push out a whole new set of leaves. Depending on time of year, those leaves could mature fully. Sometimes they don't if it defoliates really late.

I am in an area of the country where we have really high humidity. It's very common for us to get fungal issues. Again, very rarely do I see them be fatal to the tree. Certainly makes them look not as we would hope. If the aesthetic value is really what you're going for, there are protocols where we can manage those diseases, keep more leaves on the tree, and keep them looking better throughout the season. As far as killing the tree, probably not.

Doug: Well, what should I do? [laughs]

Mike: That's the conundrum, right? That's the conundrum. There's a lot of things like that we deal with where you're not going to know until that ship has sailed. If you don't treat, you're not going to know until it's too late whether or not that tree is going to live through it.

Doug: They come every six months to look at my trees. I'm doing a television show sponsored by Davey. A Davey arborist will be here today. We'll be filming today. Maybe I'll talk to him about it, and maybe he'll convince me to treat it. It would be just some kind of fungicide that they would put on there to keep the leaves on there?

Mike: Yes, fungicide sprayed at a regular interval. Typically, we're going to rotate fungicide so we don't get any resistance. Beyond the fungicides, deep-root fertilization, great process to help that tree have all the nutrients it needs to regain its strength after something like that.

Doug: That's another thing I should be doing more of because right behind it, I've got a nice pink dogwood that just-- it blooms, and it does okay. It's got a nice spot in that it's an understory tree. I'm telling you, if that thing got fertilized, it would be a monster. It would be a beautiful, beautiful tree. Talk a little bit about that. We've done it on the podcast before, but it's an important part of keeping trees thriving, right?

Mike: It is. We disrupt a tree's natural cycle with what we do in the landscape. We're always cleaning leaves up. We have turf right up to the base of the trees. We're not letting that natural recycling of nutrients occur. Normally, in a forest or in an open, naturalized area, you're having a deciduous tree defoliate at the end of the season. Those leaves drop to the base of the tree. They compost and add nutrient back into the soil, and then the tree sucks it back up.

When we're out there with our lawnmowers and backpack blowers cleaning up all the leaves, we don't allow that to happen. I think you can see it in our soils. If you put a shovel in a forested situation and look at the difference between the soil there and the soil in a suburban lawn, distinctly different. I think the deep-root fertilization is incredibly important to replace those nutrients that we are carting off our properties every year.

Doug: You just said something that makes me happy because I leave my leaves underneath that dogwood. I'm not doing it to make it a better tree. I'm doing it because I'm lazy.

Mike: That's a valid point. The way I look at gardening and the way I look at maintaining my property at home is it has to be enjoyable. It can't be a chore, right? If we start to turn this stuff into a chore, you're less likely to go out and do it. I don't haul anything off of my property. Now, I compost. I grow vegetables. I chop up my leaves with my lawnmower and either use them in the beds or just put them back into the lawn. Nothing leaves my property.

Doug: Yes, it's funny. I'm doing the same thing. Again, as I mention often on the podcast, I live in an oak forest. Those oak leaves, they're tough to break down, but you shred them up, and you give them a couple of seasons. You use them with my compost. They are just a great thing for the garden, for the lawn, for the trees. I've got a spot where somebody has been either raking or blowing leaves over since 1939. You get underneath there, and you've got what we call black gold, Mike. [laughs]

Mike: I'm in a suburban neighborhood. I don't have a ton of trees. There's two silver maples that are just over my property line that I get leaves from. I don't accumulate enough. I would mulch all my beds with leaves if I had enough. My neighbor thought I was a bit nuts. He was new to the area. He didn't really know what to do with his leaves, so he blew them up against the back property line. One weekend, I was out there, and I asked him. I said, "Tanner, you're going to think I'm a lunatic, but can I blow your leaves into my yard?"

[laughter]

Mike: He allowed me to do that to bolster my supply.

Doug: That's the definition of the best neighbor ever. "Can I blow your leaves into my yard?" [laughs]

Mike: That's what I thought, too. That's what I thought, too.

Doug: What else comes to mind to keeping the spring trees doing their thing?

Mike: Just an inspection by an arborist. I talk about this all the time. I talk about this with my clients. I talk about this every opportunity I get on podcasts or being interviewed. I think the most important thing you can do, and a lot of times, it is free, is to have an arborist come out, identify the species, give you ideas of what to look out for, make sure it is a certified arborist, hopefully from a TCIA-accredited company. That is the best time you can spend to learn about your property.

Doug: What I love about that is, in my case, again, every six months, and oftentimes, I've got a list of things and I'll say, "Well, I think this is a problem. I think that is a problem," but a certified arborist will look beyond that. That's what I love. We'll see things that I didn't see. It's been a godsend for this property in saving a garage, and making sure I can get up and down my driveway because I didn't know the tree. I didn't even recognize it. I'm the guy hosting a podcast about trees, and I did not recognize two trees that were dead and ready to fall. One on the garage and one across the driveway.

The arborist was just like, "That's not just your problem, what you said, this front tree. There's a tree behind here that's going to--" and I'm like, "Oh, thank you." Again, I tell people this as often as you do, Mike, "Get a certified arborist to take a look." They're bound by a code of ethics. This isn't somebody that's trying to sell you something. It's the antithesis of that. It's someone telling you that this is a problem, or I'm sure you go to properties all the time. It's just like, "This is not a problem."

Mike: All the time. All the time. People don't know what is and what isn't a problem. A big portion of my job is just educating folks. I think to your point about every six months, I fight the battle to get people to get us out there one time. If you're already there, multiple times a year is ideal, because there's things that I can see in the wintertime that I may not spot when a tree has a full canopy.

There are things that can hide in a forest, amongst the leaf coverage. I always tell people, "I like to get out there at least once in the dormant season, once in the growing season." Dormant season, we inspect for structural integrity, any defects, things like that. Then the growing season, we get a much better picture of overall health, vascular health, and those issues. Get us out there once. Even better, get us out there twice a year.

Doug: It has to be twice a year for me. I'm on four acres, and it's a declining oak forest, as many oaks are declining across the country. I have oak wilt going through the forest, and so I just need to know what's healthy, what isn't, what should go, and what should stay. Then the fun part, which we'll talk about coming up, the fun part is replacing those oaks with something else, with something diverse, and something cool, and oftentimes something native. Anything else left on getting spring trees to thrive before we move on to favorites?

Mike: Certainly pruning. Pruning is important with all trees. I tell people a lot, I think of trees like my children. They are easy to mold when they are young. Once they get older, it's tough to really change what you're working with. I work a lot with the structure of a tree, making sure to guide that in the right way when the tree is a juvenile, so that it's set up for success as it grows.

Doug: Boy, pruning has to be done right. I know that you see it because I see it every other day. Pruning that's done wrong. When I go to the dentist every six months, the seed is out towards these flowering crabs. The other dentist, I know he's doing the pruning, and it's all wrong. [laughs]

Mike: Part of the problem there is people don't know it's wrong. When the homeowner or the property owner hires somebody, calls a tree guy or whoever, their buddy that says they can prune trees, they don't know what they're doing is wrong. Again, education is a big part of it. Like construction damage to trees, pruning can have big implications to the overall health. Although most of the time, it's not super-fast, where you would see the results. A lot of times, people don't correlate, "Okay, this giant pocket of decay is because of the poor pruning that I had done five, six years ago."

Doug: Well, it's funny in this situation. They've been in this office about, gosh, 15 years, and I'm always seated in the same spot. I'm friends with them. I see them at different events. Every other time I see the one dentist who's doing this pruning, I say, "Right down the road, they've got a place that gives a free pruning demonstration." He doesn't listen. [chuckles]

He's stubborn, and he just does it his own way. I feel that each probably two years, that I look at the trees, I'm like, "Oh, this is just a matter of time. This is just done so poorly." I always say it's art and science. Not everyone else agrees with me, but I just think the importance of pruning the right way, or at least learning to prune the right way, is critical with trees and your landscape.

Mike: Absolutely. I agree with you 100%. It is art and science. There is proven processes that we follow, places to cut, ways to cut, all those kinds of things. When we're talking about a dentist's office or other commercial properties, a lot of times, those folks are worried about visibility and things like that. They think the best way to get visibility is to cut the tree down, top it, reduce it, when, a lot of times, they're not taking into account the sight line that the person may be viewing their sign. A lot of times, it's better to raise the branch level than try and reduce the height of a tree. That doesn't even take into account the way the tree responds when you do that, because anytime you prune, you're stimulating growth. It is absolutely an art and a science. Absolutely.

Doug: Ready to move on to some favorites?

Mike: I am. I hope I don't have too many. I have quite a few.

Doug: We're going to go. We'll go all afternoon if we have to on favorites. I'm throwing in some of mine, too. You start, Mike. I bet you, they'll be some of the same.

Mike: I bet you they will. Like you, I tend to focus on natives where I can. There are certain things that I've come to love over the years that just cue different emotions and memories for me. Witch-hazel is one. Witch-hazel is one of the first things that really gives me a taste of spring. I'm lucky enough. I'm about 10, 12 miles away from Longwood Gardens. I get to go out there quite regularly. I'm a member there. I take my kids out to let them burn off some steam. I always make it a point to go to Longwood when the witch-hazels are in bloom, because it's the first thing that really makes me feel like, "Hey, spring is coming. It's close. It's close."

Doug: That's a favorite of mine, too. I've got a native, but I also have a nativar. I've got one called Diane that has red flowers. I'm like you. Even though I'm in deer central, once this tree got tall enough that the deer couldn't get the buds-- and they don't always eat it. It's not their favorite, but you know deer, they'll eat anything. Running out, starting in January, depending on how the winter ends, to look at these trees to see when they're going to be blooming. I'm right with you there, Mike. There's no stopping us once the witch-hazel blooms.

Mike: That's right. That's right. Look, nativars and those kind of things, that counts in my book. I try and do the 80-20 rule if I can. I'm probably more like 70-30 where I try and do natives where possible, but there's stuff in my garden that's not native because I like it. I'm not going to discount it just because--

Doug: That's what I tell people, too. Yes, it's important to have natives. We want to plant them, but there's also things to plant for you. We're planting some things for pollinators and wildlife because it's a good thing, but there's also a reason to plant things for you. What's next on your list?

Mike: Serviceberry, right up there with witch-hazel for me. I actually bought the house I grew up in. I think we talked about this on one of the prior episodes. When we moved into the house that I had been living in for a long time, my kids and I planted a serviceberry at our back fence line. It was two-fold. I wanted to plant a tree with my kids when we moved in so they could watch it grow.

I also wanted to camouflage my neighbor's not-so-attractive fence. Serviceberry, really cool tree, a lot of value, also gets foliar fungal issues. I'm not overly concerned with that. It's in bloom right now, up against a red fence with its white flowers. It looks fantastic. Fall color is great. I like it because it's the one I grow. You can buy single-stem varieties, but mine's more natural. It's more of a multi-stem tree.

Doug: All right. This is getting scary because I got a multi-stem serviceberry out there blooming right now. Is the red fence the one that you don't like?

Mike: Yes.

Doug: Well, it's got to set off those white flowers, though, right?

Mike: It does. It does. It's just one of those fences where it's seen better days. It's a little tired. The root flare of the giant silver maple there is pushing up on the bottom of the vinyl fence that's my neighbor's. One panel's all buckled. I'd rather look at native plants than this fence. [chuckles]

Doug: Well, it's funny when you live at a place for a long time, you become blind to that sort of thing. [chuckles] After serviceberry-- oh, you know what? I want to ask you about serviceberry. Do you ever get the berries? Usually, the birds get them before I do.

Mike: Yes, the birds. Again, rust diseases get the berries. I'm not growing it for the berries. Honestly, my wife has a strict policy of no fruiting plants. I didn't go into it with her. She's not a plant person. As long as I keep the name "berry" out of it, she won't really throw too much of a fit.

Doug: It's a service tree.

Mike: That's right. That's right. Shadblow. It's a shadblow.

Doug: No mulberries.

Mike: No. Yes, I very rarely get to enjoy the berries. Again, just the structure of trees is really cool to me. I try and do things that have multiple seasons of interest. Everybody thinks of the flowers when they think of a small flowering tree or spring-blooming tree, but there's a lot of interest beyond that. Like you said, the berries, a lot of them get good fall color on them. Then, just to be able to appreciate the branch structure of certain things is a nice additional season of interest.

Doug: Well, I love my serviceberry. What's next on your list? Let's see if we can match again.

Mike: The two pretty common ones that everybody thinks about are redbud and dogwood. There's a ton of different options in dogwood. Redbud has come a long way. There's a lot of options there, too. I still tend to lean towards the natives. Even in the dogwoods, there are some hybrids between kousa dogwood and American dogwood. There's just something about a really old American dogwood that does it for me. The bark, they get gnarly. Again, when we talk about structure, the structure of a really old American dogwood is just-- I could look at it all day.

Doug: I have them all through the forest. I love them, too. This story will break your heart, Mike. The neighbor was doing work or having somebody do work. The other neighbor on the other side of the property called me and said, "Hey, man, I think that guy's on your property." I went down there, and he destroyed a 40-year-old native dogwood, one of my favorite trees.

Of course, the neighbor was beside herself. She came up to the house. She's like, "I didn't know he was going to do that. I'm so sorry." What are you going to do? I've got other dogwoods in the forest. I wanted to ask you a little bit about that, about my feelings for the trees. You seem to, certainly in your business, have them too. I'm sure you've come across a lot of this where people just love their tree, and it must feel good to be able to save it from your point of view.

Mike: It does. Sometimes it's not saving it. There are some times that we do things just to preserve it as long as possible. As long as the tree is not a hazard, if you are still getting enjoyment out of it, let it stand. We certainly can't let things be a hazard, but I think there are far too many trees being removed. I think people are getting bad advice out there. There are certainly things you can do to help preserve a tree for as long as you can.

The cherry blossom festival in DC just happened. I was reading an article a few months ago about this big fight over one of these cherry trees. It's right on the bank of-- I forget where it is down there. This thing, a lot of people want to preserve it, but it left one little limb, left a big pocket of decay in the trunk. It's not hurting anything, though. It's not going to fail. It's not going to hurt anybody or anything. In those cases, if you're still getting enjoyment out of it, let it stand. Let it stand.

The other thing we need to think about, and this is a point about dogwoods and redbuds. A lot of times, when we're thinking about a tree to plant, especially in suburban landscapes, we're thinking about lawn area or out front. That is not where these trees, especially dogwoods, redbuds, prefer to grow. They are, like you said, understory trees. You try and jam a native dogwood right out in the middle of your front lawn that gets 10 hours of sun a day, maybe not the best choice.

Doug: Even the word "understory," we use it. When you say "understory," you know what it means. You say understory to a lot of people, they're just like, "What do you mean understory tree? It's just a tree." I'm like, "Some like to be in the shade. Some like to be in the sun." I hate to go back to it because we always talk about it. Right tree, right place. [laughs]

Mike: Right place, yes. Very important. I'm getting ready to give a talk to a garden club this winter, and that's the topic they picked. It's one I suggest a lot of times. Part of the problem is, as you're driving around, I'm sure your town is the same as mine, you drive around here. You almost see more examples of what not to do than what to do. People get trained in thinking that it's either okay or worse, yet the right way to do things when, in fact, it's not. You get that with mulch volcanoes, trees in the wrong spot, all those things.

Doug: I think it's also very prevalent in new construction, where they'll stick these plants in really close to the house, and it looks great today. The first thing I think about when I drive by, and I always ask arborists, "What is it like to be in your truck or in your car when you drive by this?" My wife, it drives her nuts. I'm like, "Look at that. In five years, that weeping cherry, they're going to have to-- and they're paying all this money." It's the same thing. What's really funny about this is my wife's not a gardener, but there was a building close to us that was redone. She came home one day and said, "Did you see how close those trees are planted to that new building?" I'm like, "Through osmosis, she has learned."

Mike: That's right. That's right. My wife picked up a couple of botanical names from me, so I'm happy about that. Probably the most egregious one I see is river birches. New construction, three river birches, five feet off the front corner of these houses. It's like, "Man, you have no idea what you're signing up for."

Doug: Anything else on the favorite list?

Mike: I can't leave off cherry. I grow okame cherry. Again, I planted it. I live in the house I grew up in, so I planted this okame cherry when I was just getting into plants. I was probably 15 or 16 years old, living with my parents. They wanted me to do some landscaping work, and I planted this tree for them. It's seen better days. It gets scale on occasion. It's gnarly because I've had a branch or two knocked off it. Again, okame is one of those really early blooming cherries, so another really promising sign that spring is right here. That's really what I need coming out of winter is some assurance that spring is coming. That okame does it for me every time.

Doug: Well, Mike, that was great stuff and a lot of fun. I bet you we could go on, as I said, all afternoon about our favorite trees. I'm glad we had a few that matched there. Thanks so much for your time, as always. I'm sure we'll talk to you soon.

Mike: Thanks, Doug.

Doug: I love talking to Mike. I think you can tell. I'd like to find out what he's growing in that vegetable garden, too. Maybe next time, I'll ask him. All right, fellow tree lovers, I want you to tune in every Thursday to this Talking Trees podcast from the Davey Tree Expert Company. I am your host, Doug Oster. Do me a big favor. Subscribe to the podcast so you'll never miss a show.

If you've got an idea for an episode, maybe a comment, there's two ways to reach us. You can send an email to podcasts@davey.com. That's P-O-D-C-A-S-T-S@D-A-V-E-Y.com. You can also click the link at the end of our show notes to text us a fan mail message. Your ideas might be on a future podcast. We'd love to hear from you. As always, we like to remind you. On the Talking Trees podcast, trees are the answer.

[00:28:05] [END OF AUDIO]