Talking Trees with Davey Tree

The Science of Trees, Fungi & Diseases

April 08, 2021 The Davey Tree Expert Company Season 1 Episode 13
Talking Trees with Davey Tree
The Science of Trees, Fungi & Diseases
Show Notes Transcript

Chrissy Balk,  technical advisor for the Davey Institute, teaches us all about the science of trees, such as how photosynthesis works, how trees help with storm water runoff, how they clean the air and types of fungi and diseases. 

We're celebrating Arbor Day all month long with the Davey Planting Project Giveaway! We want to promote tree planting this Arbor Day, so we're giving away tree seeds to anyone and everyone who is interested! All you have to do is email a mailing address to podcasts@davey.com and you'll receive your complimentary seeds in the mail along with planting instructions.  You have until the end of the month to send us an email for your seeds. *Seeds can only be mailed within the U.S.

In this episode we cover:

  • Photosynthesis (2:05)
  • Storm water runoff and erosion (3:11)
  • Cleaning the air (4:01)
  • Human benefits (4:33)
  • Trees Chrissy has planted (6:14)
  • How Chrissy started her job (8:27)
  • Fungi (10:55)
  • Diseases (12:05)
    • Tar spots on maple leaves (12:20)
    • Pine Wilt - Pinewood Nematode (13:13)
  • The best part of Chrissy's job (18:22)

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

To learn more about various types of tree fungi, check out our blogs on Tree Fungus.
To learn more about common tree diseases, read our blog, Common Tree Pests and Diseases to Look Out for this Spring

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

Doug Oster: Welcome to the Davey Tree Expert Company's podcast, Talking Trees. I'm your host, Doug Oster. Each episode showcases one of Davey'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.

Welcome back tree and nature lovers. Before we get to our guest, a reminder that you can get free tree seeds as part of the Davey Planting Project in celebration of Arbor Day. All you need to do is send an email requesting seeds to this address. It's podcasts, plural, @davey.com. Let me spell that for you. P-O-D-C-A-S-T-S@davey.com, that's D-A-V-E-Y. We'll get those seeds right out to you.

This week I'm joined by Chrissy Balk as a technical advisor for the Davey Institute. Chrissy, I think we're already kindred spirits. You are from my hometown of Cleveland. You love plants like I do. We were supposed to do this podcast yesterday day, which you had to take the dog to the vet and I was worried all day long. I was checking my text, hoping everything was okay and everything was all right. What's next? Are we going to have to trade recipes and get a play date for the dogs when I come to visit my friends in Cleveland?

Christine Balk: Maybe plant some trees together.

Doug: Oh, that's a good idea. That's a great idea.

Chrissy: Yes, dogs and trees are basically my life along with fungi.

Doug: We're a little bit out of my wheelhouse for the topic today, the science of trees, so you're going to have to school me. Let's start off with photosynthesis. Now, I'm going back to like sixth grade, trying to fill out all those little things on a leaf to say what's what. I bet when you were doing that in school, you got everything right.

Chrissy: I did always love science. It was always math and science for me. Don't ask me how to spell a word though. In general, photosynthesis is pretty easy. Basically, the plant just needs the chlorophyll, which is what takes in the light energy, and then it also needs CO2 and then water. It takes those things and then converts it into food for the plant, which is basically carbohydrates. Also, releases that oxygen that we benefit from every day, that we breathe, and helps us to basically live. That's photosynthesis in a nutshell.

Doug: Well, sure. We know one of the great benefits of trees is creating that oxygen that we breathe. Let's talk a couple other scientific facts about trees. How about using trees for stormwater problems? Is that something that's happening?

Chrissy: Yes, trees are great for stormwater runoff. They uptake a lot of that excess water. They also create a barrier for that water so it moves more slowly through the soil, therefore, you're not overwhelming the storm systems and potentially causing flooding and stuff. They really help in that sense. Trees are also great to help prevent erosion. Because of their roots, they hold the soil together. That's another big benefit in terms of things that we can use them for in the environment besides their beauty and their oxygen source. I could go on all day about the benefits of trees though.

Doug: Keep going then, I want to hear all the benefits of trees.

Chrissy: They also clean the air. They can take out CO2 obviously, like I said before, they use CO2 to create photosynthesis. They take CO2 out of our air, which we know there's way too much of that, and that caused a lot of issues in terms of climate change and stuff like that. It actually takes that out and other pollutants out of the air. They just have so many different benefits like that. Basically, if there's a problem in nature, trees can solve it. At least I think so.

Another benefit of trees is that they make us happier as humans. There's been a lot of studies done that in neighborhoods where there's not a lot of trees like my neighborhood in Cleveland, people tend to be less happy, there tends to be more crime, things like that. Then, if you go to a neighborhood where there's a lot of trees, people tend to be happier and less crime. It just makes people happy. It's proven.

I'm currently trying to plant many trees on my street. I don't have a large lawn, but I've already planted five trees on it somehow. I'm trying to bring that energy to my area and just make sure my neighbors understand the importance of trees and how happy they can make us and how they can benefit us. They can help your house cool down. They can again, take that stormwater up for you. They do a lot of things to actually save you money as a homeowner. I try to always tell my neighbors like, "It's not just me being the crazy tree lady, plant your trees because they're going to save you money, make you happier, do all these things."

They're just awesome and such an easy thing to do. There's so many cool programs out now too. A lot of cities are trying to help people to plant trees and give them options for that, provide free sources. Arbor Day always has cool ideas for giving you free trees. There's always options for people to plant these trees, we just need more people to do it and then take care of them after. If you're not taking care of a tree after you plant it, then it's not going to thrive in the urban environment. That's another thing we have to be aware of.

Doug: Why did you put in, in your property?

Chrissy: I have a Magnolia and then I have two arborvitaes. I guess I might have lied. There's only three trees now, but I have a lot of other plants, few Rhododendrons and Hydrangeas and stuff like that. I tried planting on the tree lawn this year, but then the plows came everything out so I'll have to replant this year again.

Doug: Aww.

Chrissy: Yes. I was bummed out by that, but whatever fits and will thrive.

Doug: Why Magnolias?

Chrissy: I just think they're beautiful and they're pretty hardy trees, so those two things put together. Also, I said before I don't have a large lawn. I live in Cleveland, so it's a smaller tree. I'm not going to plant like a dawn redwood in front of my house because it's just going to get way too big too quick. I tried to pick a medium-sized tree that would look beautiful, although it's already starting to bud out right now and I'm a little nervous. It's getting faked out as Magnolias do. One of the first things is to bloom and then a frost usually comes. Hopefully, that doesn't happen.

Doug: I also have a Magnolia and I love it. Whoever planted it, planted it in the woods which is a weird spot. Every few years, I don't get the blossoms. For the most part, even though right now in your situation and my situation, the buds are swelling, you don't know what's going to happen. For the most part, they bloom and when they do, talk about happiness.

Chrissy: Yes.

Doug: When those flowers are out, boy, you can't help with smile, right?

Chrissy: Yes. That's the main reason I planted it because of that. They're beautiful and they're plentiful. Their canopies are just really large and pronounced. I just think they have really pretty canopies which my street needs. As I said, there's not a lot of trees and I'm trying, and so I wanted something that stood out and made the neighbors jealous in a way that makes them want to plant trees. I'm on the mend.

Doug: Tell me a little bit about your path to the job that you do and your love of trees and obviously a love of science.

Chrissy: I grew up in Buffalo, New York. Every weekend, my parents would take us on a hike or something like that. I grew up going to the Adirondacks as our family vacation every year. I grew up in nature really, so that started it for me. Then, I went to college at St. Lawrence which is Upstate New York, near the Adirondacks. There, I found classes that I could take that were ethnobotany and botany, and mycology. It brought all things plant pathology together for me and made me realize I love all these things: I love fungi, I love trees, I love plants.

After that, I went to Alaska on an internship and collected native plant seeds for a while. It was awesome. Loved that, decided I really want to work with trees and fungi. I did some research, found plant pathology, and then I got my master's at Ohio State for that. Here I am, then I came to Davey with all of that. I've had a pretty, I like to call it a call of fate, basically. Every time something's happened to my life, it seems just pretty natural. I guess that it's funny. It's been a natural thing for me, nature and trees.

That was my track. It's definitely a little weirder than I made it seem. There's some bumps in the road of course, but this is where I was supposed to end up; working with trees, teaching people about it, getting them excited about them, getting them excited about fungi because that's how I got into it, excited people talking about it. It makes people want to learn and makes them want to plant trees and do all these things. We need them, they're the fate of our future. That was my path.

Doug: Buffalo, Cleveland, Alaska. I'm seeing a pattern here.

Chrissy: I like cold weather.

Doug: Cold.

[laughter]

Chrissy: I do not like the heat, that is for sure.

Doug: I want to talk about fungi. Tell me a little bit about how fungi work with working with trees.

Chrissy: We deal with fungi all the time in the world of arboriculture. Most people think all mushrooms and fungi are bad and there's so many good ones. There's even ones that actually form a symbiotic relationship with plants called mycorrhizae fungi. They form basically new roots with the trees and the fungi help the trees to uptake nutrients and whatnot. Then in return, the fungi take nutrients from the tree so that they can survive and thrive because they can't make their own food like plants can.

They form this symbiotic relationship and they can be really beneficial for each other. That's one way fungi are great. Another way is they decay all excess matter. If we didn't have decay fungi, then we'd have just piles of debris in the forest. We need that there to uptake that and degrade it.

Doug: I know that another one of your expertise with plant pathology are diseases. That can be a sad thing for a homeowner but it can also be a relief. Let's talk about one, and I hear all the time is maple leaves with a black spot on there. It looks really scary but what is it?

Chrissy: Oh yes. I know exactly what you're talking about without seeing it. That's a tar spot on maple. In general, it is harmless. It's not something that we even recommend you spray for, but it is just a fungus that causes those leaf spots. They're very dark. They do look scary but they're not actually doing any harm to the plant. Only thing they're really doing is covering up some spaces on those leaves so that the leaf can't produce more energy from that. It's covering up that spot to not allow photosynthesis basically. That's the problem with that. In general, it's harmless and nothing you should worry too much about.

Doug: As a plant pathologist, what are you worried about? Are there things that you're looking at now that are expanding and that you are concerned about, or there are too many things to even talk about that you're concerned about it?

Chrissy: I was going to say that's opening a can of worms. As a plant pathologist, I tend to love the reaction of a disease with its host plant. The main thing that came to mind when you said that was, I've been looking into pinewood nematode recently. Pinewood nematode is actually a nematode that causes pine trees to die. Within a month, it kills these trees. It's actually a pretty cool complex. Pine sawyer beetles actually vector this pinewood nematode and vector them into the tree. Then typically, the nematode actually has a blue stain fungus on it too. All these things come together to stress the tree out.

Ultimately, the nematode kills the tree but the blue stain fungus also clogs up the vascular system of the tree. The reason I'm nervous about this disease particularly is because there's climate change, temperatures going up in general in the world, these nematodes thrive with the heat. It's becoming more prevalent and that's really worrisome in terms of our pines on the east coast and the forest. I just don't want it to turn into something like sudden oak death in the west. It's something that I think we all need to be aware of that it's becoming more of a problem and it kills the trees within a few months, sometimes weeks. That's my main worry when you said that.

Doug: At this point, is there anything we can do or not?

Chrissy: Yes, there's some products that you can use. It depends on who you talk to, how effective they are. There's some nematicides like emamectin benzoate, can be effective towards treating pinewood nematode but timing is really important. If the tree's already infected, you can't do anything. This would be more of a preventative. It would not be something that would get rid of the nematode once the tree was infected.

Again, it depends on who you talk to, how effective they think it is, and whatnot. There's not a ton of research that was put out in terms of efficacy. That's the only worry I have there. There are options that we can take into our consideration and use. I think just being aware also that this is something that is becoming more prevalent. If we are aware and know it's coming, then we can be on the lookout and preventatively treat trees. Timing is everything with this kind of things.

Doug: It's always scary when some disease or pests becomes an issue, but it seems oftentimes hopefully nature finds a balance. I always cross my fingers when I'm talking to somebody like you Chrissy because that description was scary.

Chrissy: I know I always bear the bad news. I make jokes like, "This is why I don't go on to properties. This is why I'm not a sales arborist because I tend to bring the negative." Yes, it's scary. It is scary and especially things like that with climate change. You hope that nature can mend itself like it's done so many times over again. It's always worrisome especially with invasive pests and stuff like that, invasive species of fungi, anything, it's all just scary. It seems like we can't really learn from ourselves, our past mistakes. We keep making the same ones you and that's also scary.

Things you can do though to prevent so much worry from certain diseases or pests don't plant the same tree, don't do a monoculture. That's something so big that we can take away from this. If you're planting a few different trees, plant four different species. If you're planting just one tree on your block, if your block's filled with a bunch of sycamore, then plant something else. Just don't have that monoculture. Therefore, if there is something rolling through that's affecting your one tree, hopefully, it's not going to affect yours. You only lose 1 tree as opposed to all 20. That's a huge thing to remember.

Doug: Well, that's great advice. Let's finish on a positive note. Tell me what you get out of your job. What the best thing is.

Chrissy: I love just making people excited to learn about trees and fungi, just getting them aware of how important they are but just getting them excited. I'm a pretty bubbly person. Again, I learned to love trees and fungi because of the teachers I had. They were so excited about it so I just love when my energy goes off on someone else and I see myself through them and their excitement of trees and fungi and I know that I brought that to them. I love that I can teach about it all day. It's really great.

Doug: Well, when I come back to visit in Cleveland, I expect to see that neighborhood that you're living in filled with tress down the entire street, okay?

[music]

Chrissy: I'm trying.

Doug: All right. Thanks so much, Chrissy.

Chrissy: Thank you. Have a great day.

Doug: Tune in every Thursday to the Talking Trees podcast from The Davey Tree Expert Company. I'm your host Doug Oster. Next week, we'll continue our month-long celebration of Arbor Day with some great stories, fun interviews, and how about a little forest bathing too? Don't forget to email podcasts@davey.com. That's P-O-D-C-A-S-T-S@davey D-A-V-E-Y, .com for your free tree seeds as part of the Davey Planting Project, a celebration of Arbor Day as I said. You've got untill April 30th to get those requests in. As always on the Talking Trees podcast, we know the trees are the answer.

[00:20:16] [END OF AUDIO]