Mushrooms and other Fungi in Florida | Coast to Canopy

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The day we recorded this podcast episode, I set a record for the least amount of ground covered in a WFSU Ecology field outing. As one of my guests told me, you don’t burn a lot of calories as a mycologist. We spent two hours looking for mushrooms at Wakulla Springs State Park, and you can see just how many we found in the banner image above. We walked maybe 100-150 feet.

When we think of ecosystems, we think of plants and animals first. Then, during the warm and rainy times of year, mushrooms pop up in a variety of forms, and we notice them. These are reproductive structures, like flowers on plants. When we harvest so many in so small an area, it gives us a glimpse into how much fungi there is hidden in the soil, wood, and other bits of plant matter, like magnolia cones. For all the fungi that produce visible fruitbodies, there are many more helping to drive this ecosystem. They’re there even when we don’t notice them.

Fungi capture the imagination. We get excited when we find chicken of the woods or a large patch of chanterelles. Some folks are a little more adventurous and try to find the edibles with highly toxic lookalikes. Many of us associate mushrooms with toxicity more so than food; toxic for us and undesirable on a lawn. And then there’s that Wood Wide Web that allows trees to talk to each other. Sounds magical, but is that how it really works? We’ll talk about that.

We’ll talk about all of it- edible and poisonous mushrooms, mushroom ID, and the many things fungi do in our lawns and forests.

A few words to know

Here’s a cheat sheet of mycological terms.

• Mycorrhiza: Fungi that form symbiotic relationships with plants, through their roots.
• Ectomycorrhiza: A subclass of mycorrhiza, these fungi connect to plant roots without penetrating the plant tissue.
• Saprotrophic: A term describing the decomposers. These fungi break down wood and other vegetative matter, making it soft enough for insects and birds to nest in, and ultimately driving the process of turning wood into soil.
• Convergent Evolution: Not specific to fungi, this term describes when the same types of features or behaviors evolve independently in different groups of organisms. For example: there are many species called coral mushrooms that look alike, but these distinctive structures evolved in different orders of fungi.
• Coprophilous: Fungi that grow in herbivore dung. In our archeology documentary, Finding the First Floridians, we learned how archeologists used coprophilous fungal spores in sediments to determine when megafauna such as mastodons went extinct. This group also includes magic mushrooms, which I wasn’t going to ask about, but then I did.
• Hyphae: The thread-like structures that make up the mycelium, the body of the fungus.
• Fruitbody: Another word for mushroom. A reproductive structure that releases spores into an area.

Meet our guests

Dr. Matthew Smith is a professor in the University of Florida’s Department of Plant Pathology. As part of his appointment, he is the curator of the Fungal Collection at the Florida Museum of Natural History, and he identifies fungi for the UF/IFAS Extension and the Poison Control Centers.

Alissane Sow is his PhD student. His dissertation focuses on relampago blight, which we saw plenty of at Wakulla Springs.

Coast to Canopy blog posts are curated transcripts, a distilled version of the longer conversation we hear in the embedded episode. My notes appear in italics.

Mushroom Diversity: There’s quite a lot we don’t know

Matt Smith: In the modern era where we’ve used DNA evidence, we know the diversity of fungi is really high. The estimates fall somewhere between two-point-five and four or five million, depending on who you believe, and which study you listen to. But it’s a lot of species.

But there’s only about 150,000 species right now that have a Latin name and are formally recognized. So this huge gap between what we know is out there and what has a Latin name. In comparison, plants, there’s a little over 300,000 species. And so, in comparison, there’s a lot of fungi that we still don’t know what to call them. And they haven’t been officially discovered by science, but we know they’re out there.

DNA sequencing has revealed the surprising evolutionary history of fungi

Matt Smith: Any ecology that you see in fungi, and almost any morphology that you see in fungi, has evolved multiple times. That’s a a common theme among fungi. For example, I study a lot of ectomycorrhizal fungi. These are the fungi that are symbiotic with the roots of trees like pines and oaks.

This is something we know is evolved more than 70 times in different groups of fungi. So, the fundamental way that they get their energy, through this symbiotic association with plants, that shows up a bunch of different times in different groups. Similarly, we looked at coral fungi (on our foraging trip) and we saw three different ones. Two of them were mycorrhizal ones, and one was a saprotrophic one.

And those look quite similar. If you didn’t know already what they were, you’d say, oh, “There’s a bunch of coral fungi. They’re probably related to each other,” But they’re in three different orders. That’s an example of convergent evolution. And certainly, convergent evolution happens in a lot of groups of organisms. But in fungi I think this the soft fruiting bodies, they can change really fast in evolutionary time.

It makes it hard to study fungi because when you look at them, you can’t always tell right away which group you’re dealing with, which order they belong to. So, that makes it a challenge.

Mushroom identification: take a lot of photos

Alassane Sow: It’s having a lot of photos.

Distinguishing features are different for different types of mushrooms. Generally you want to have a photo of the top, the surface. If you’re taking a picture of like a characteristic mushroom, you want the cap. And then you want the pores or the gills or whatever it has, because that can separate a lot of mushrooms.

Alassane Sow: And then you also want a picture of what it’s actually growing on, because it’s very informative. If it’s growing on wood or on the soil, or near water or near the road or in a lawn, that can all be very informative because there’s, as we saw (at Wakulla Springs), there’s a lot of fungi that look very similar that do very different things. And that can be a hint to differentiate some.

Matt Smith: The other thing I’ll add to that is when people are harvesting them… they can learn to see these cues. Sometimes you can see the spore color on that mushroom itself, there’s a place where the spores are being deposited. It’s kind of sticking to the stipe and like, oh, this one has brown spores, not white spores.

That can be really important for because sometimes you have two things: one has brown spores and one has white spores. But otherwise, in the forest they look really similar. The other thing is sometimes when you’re harvesting it, you will touch it and it will change color a little bit or it will release some latex like we saw in the field today.

How much damage do we cause by harvesting mushrooms?

Alassane Sow: Let’s imagine a rotting piece of wood that has mushrooms coming out of it. A vast majority of the fungus itself will be these thin, thread-like cells that are the body of the fungus. And those are the hyphae, and they make up the mycelium, and that’s most of the body of the fungus.

Throughout the whole year, it’ll live in that wood and decompose that wood. And then, when it’s wet enough or humid enough, it’ll fruit and make that mushroom. By picking that mushroom, you’re not killing the fungus that’s in the wood.

Maybe you’re doing a little harm, because it took a lot of energy and time to make that mushroom. But it’s still able to disperse its spores, and it’s still able to make more mushrooms. And oftentimes, there’s a lot of mushrooms that don’t make just one mushroom at a time, they’ll make multiple. And so if you pick some and leave some, I think you’re not doing very much harm at all.

Even toxic mushrooms are safe to touch (at least, in North America)

Matt Smith: There are some mushrooms people get concerned about. There are some that are varying levels of poisonous to people or toxic to people if you consume them. One thing I like to make sure people know is that all of them are nontoxic to touch. In North America, you can handle any mushroom that you get and touch it and you can smell it, get it up close to you, and that’s fine.

Any of the toxins from fungi are only problematic when you consume them, and I only recommend people consume them when they really know 100% what it is. Because as the poison control person in the state of Florida, I don’t really want to hear about you being not careful.

Advice for those who like to eat wild mushrooms

I ask about people who seek advice on edibility from Facebook groups.

Alassane Sow: In Matt’s fungal biology class, he talks about this a lot. You have to just choose a fungus that you really want to eat or you’re interested in, and make sure you know all the lookalikes for that fungus. And you make sure that you know all the distinguishing characteristics for that one fungus before you ever are sure about eating it.

Then also ask a specialist like himself. I think getting multiple lines of evidence that it’s the correct fungus would be the right thing.

Matt Smith: I encourage people to identify a fungus multiple times, until they really feel comfortable with it. They know the environment it’s found, and they are comfortable with things that kind of look like that.

People don’t eat plants that they don’t know what they are, and that’s a good it’s a good way to not be in the hospital and hurt yourself. It’s the same with fungi. I do think with training you can learn, but the problem is sometimes people want the quick answer. They want you to answer for them. And that means they’re probably not ready to be foraging for their own food like that.

Alassane mentions chicken of the woods as an edible mushroom that’s easy to identify. However, some mushroom groups, like amanitas and boletes, have many species that are edible but that look similar to toxic species.

Matt Smith: For example, there are some edibles in the genus Aminata. But many of the largest deadly poisonous mushrooms in the US are amanitas. And so I don’t encourage people to eat from that group.

In the garden, as in the forest, healthy soils have diverse fungi

Matt Smith: In a forest, for example, if you take a handful of soil, there’s hundreds of species potentially in that one handful of soil. So it’s normal. It’s natural. It’s what’s supposed to be happening in soil to have all those organisms there. When we disturb the soil, like, for example, when they do strip mining and they take off the top of the mountain, basically, they’re taking away all of that diversity. And then they’re also leaving very little organic matter in the soil.

The same applies to disturbed soils in urban/ suburban areas.

There’s kind of a succession a lot of times. What has worked when people are trying to re-vegetate, is you bring in a hardy plant that has mycorrhizal fungi, like a pine. You bring in some of those mycorrhizal fungi and they can often get started. Over time, you’ll see new plants coming in, new fungi coming in, and this buildup of soil carbon again.

But it can take a long time for that process to happen if you’ve gotten rid of everything.

Rob Diaz de Villegas: So a lot of it starts with trees? Do a lot of tree species already come with associated fungi?

Matt Smith: There was an experiment that people did where they tried to plant pines and have pine forestry in the southern hemisphere, where pines are not native. South Africa, the tip of southern South America. And lo and behold, the pines did not grow when you brought seeds.

But if you brought seeds in just a handful of soil, you got mycorrhizal fungi. And when you bring that soil, you get the mycorrhizal fungi, and they grow great, and it’s no problem. In fact, they become invasive in some places and pines in the Southern Hemisphere, which is another issue. But, but they’re very successful in pine forestry once you have the mycorrhizal fungi.

Wood rot: the start of decomposition

Alassane Sow: There’s two sort of broad classes of wood decay that we see very often. And the first is brown rot. When you see that the wood, or the log, looks brown. It’s got this brownish/ reddish color. When you break it apart, it breaks apart into cubes. That’s because the fungi that are decomposing that plant are only decomposing cellulose, which is very easy to decompose.

White rot is caused by fungi that can compose the lignin and cellulose. When you look at that wood, it’s white and it’s sort of spongy. You can take it and you can pull apart almost like shredded chicken. There’s very little plant material left in the those types of rotted logs and whatnot.

Fungi help cycle carbon and nutrients in an ecosystem

Matt Smith: They’re critical because otherwise everything would be locked up in all this old organic material from plants. Instead, what’s happening is those fungi are breaking down that material. You can see it really well when we were looking at these brown rotted logs, they hold a lot of moisture.

You get fruiting of all these other fungi later in the succession.

Then we saw, for example, this seedling coming out of right at the edge of one of these [decomposing logs]. So, you can see this soil that’s slowly being created. The fungi are the ones that are sort of running the carbon cycling. At the same time, the other part about why the mycorrhizal fungi are so important.

What does [mycorrhizal] mean? It means they’re basically using their hyphae to go into that organic material. They’re extracting the organic nitrogen, the organic nitrogen is not available to the plants. Plants are pretty good at getting inorganic nitrogen, which is why we give them fertilizer in our garden. But that organic nitrogen is locked up in a way that the plants don’t have access.

Those fungi are growing into that organic material with their hyphae, extracting the nitrogen and trading it to the plant in exchange for sugars. That process is very important to the carbon cycling as well in the forest.

Alassane Sow: They’re important in starting the decomposition process because we saw a lot of logs that were rotting. They also had insect holes and evidence of worms and all kinds of things going in there. And also, speeding along the decomposition.

The Wood Wide Web: are plants really talking to each other?

People are awed by the idea of fungal networks connecting trees, and allowing them to communicate with each other and share resources. Matt paints a picture that sounds less spiritual than some make it out to be, and more transactional.

Matt Smith: People talk a lot about mycorrhizal networks, and it’s a cool idea. I don’t want to say it doesn’t happen, but I… think about things from the fungi perspective. I think about it in the terms of the fungus is going to do that, but it’s only going to do it when it’s good for the fungus.

Sometimes people think about the fungi as sort of these passive tubes that are just transporting things between plants, and they’re happy to be transported between plants if they get something out of it. And then the second they don’t, they’ll be happy to eat the plants.

I guess that I think it’s important to think about them as autonomous actors in this context. They are happy, and many of them, they’re happy, quote unquote, happy to act as symbionts. But that means they are getting something out of it, too, right? And that’s why it works. And as soon as it doesn’t, they won’t do it.

Relampago blight

Alassane Sow: I’m studying a fungus called Parvodontia relampaga, and it causes relampago blight on lots of different types of trees and plants here in Florida. It was described by previous grad student Matt’s lab a few years ago.

It looks like white lightning-like cords on the branches and leaves of these plants, and it’ll colonize the leaves and kill them over time. And so, if you’re on the ground looking for mushrooms, it’s very likely you’ll miss it because it’s in the canopy, in the branches above you.

Rob Diaz de Villegas: How widespread is it?

Alassane Sow: When I first started this research, we only knew it from Central Florida. But now we have collections from across the entire state and a few in Alabama.

Rob Diaz de Villegas: It’s called a blight, which to me, as a gardener, it’s a worrisome sounding thing. How worried do we need to be about blight?

Alassane Sow: Blight generally, I think it depends. I think with this blight, not very much. It doesn’t outright kill any trees, at least from my observations. It does kill the branches and some of the younger leaves, but it’s not going to destroy a forest like chestnut blight, for instance, or something like that.

In closing: be hands-on, and take lots of photos

Matt Smith: I find that many people are scared of fungi, in part because there are these deadly poisonous species that if you eat them, it’s not going to go well. I can appreciate that.

I find that when I meet people and I start talking to them about fungi, and I tell them you can handle any of these fungi, it’s going to be fine. You should smell them. You should pick them up and see them.

I like to encourage people to take the time to look at them. Don’t be afraid of them. And you might start to really think they’re cool and want to look at them more. I found that many people once they’re not scared, they can do that.

Alassane Sow: And I think a good way to get involved is just taking pictures of stuff and putting it on iNaturalist. I think many mycologists I have spoken to have found a collection of some fungus that they didn’t expect to be in one part of the country or another, by using iNaturalist. And they’re able to talk to the person who collected it and try to find out where that was. That’s very helpful.

When we were first doing this research on relampago, we thought it was only in Central Florida. We got someone posting a picture on iNaturalist of it in, I think Fort Myers. And that really was really exciting to us because we didn’t know where to go in South Florida, and we had no idea that it would even be there.