Fungi, you multitasker you; with Mark Dixon

Originally published on Running with Mushrooms in January 2024

Did you know that a forest can’t exist without fungi? In this chat, we go beyond the basics and into the (many!) crazy cool roles that fungi play in an ecosystem—guided by nature lover, scientist and educator Mark Dixon, while enjoying a forest stroll in South Africa’s stunning Garden Route.

Support & follow Mark’s awesome work here:

Reach out to Mark on LinkedIn | Follow on Instagram | Book a walk on Garden Route Trails | Garden Route Hiking Trails YouTube channel for a virtual tour of some of the outdoor hiking and adventure activities available in South Africa's Garden Route

Transcript:

(00:00:00):

Hi, Jess here. It's been a while since our last podcast.

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We were away on a mushroom tour in Uganda where we met some amazing people working with mushrooms and then on to Kenya where I was in and out of hospital with severe malaria.

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It was quite a ride. If you're curious about that part of my trip, you can check out runningwithmushrooms.com for a diary account of my experience.

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But now we're back in London. I'm feeling much, much better. So it's back to work and you can expect a new episode every couple of weeks.

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Here's an interview I did in South Africa recently.

I hope you enjoy it.

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Yeah.

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So, oh, there's a lack of photo over there.

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Okay.

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Yeah.

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I mean, yeah, just passing here, there's like another six or seven species just on this.

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Oopsie.

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I don't know if this is such a good idea.

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That was Mark Dixon being his usual inquisitive self, climbing a fallen tree that was really slippery, risking his life and limbs to get a photograph of some really cool mushrooms.

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I met Mark when a friend and I wanted to learn more about the fungal of the Garden Root.

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The Garden Root is an area that stretches along the southeastern coast of South Africa.

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It's known for its incredible natural beauty and it's an amazing holiday destination.

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You'll find a lot of outdoor activities from scuba diving to safari, but for my trip we wanted to focus on the forest, looking for our fungal friends.

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Hi, so I'm Mark Dixon living in the Garden Route here and I have Garden Route Trails which conducts a whole lot of guided nature walks and birding tours and also cycling tours.

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But in essence the concept of our guided tours is simply to get everybody to learn about the environment.

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My background, I've also done a huge amount of

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field research in three different disciplines, so ornithology, doing bird studies for wind farms and then marine biology and then my latest one is echnology, which is a study of fossilized footprints.

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What was the third thing?

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Ichnology.

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So it's fossil footprints.

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So we've got... Talking about niches of niches, eh?

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No, no, so it is.

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Whoa!

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OK, so this is what I was looking for early on.

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This is the business end of chemical processing and transformation into soil.

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The chemistry of breaking down rock and soil and that to get phosphorus out is the job of the mycelium and that then goes to the tree or the plant's roots and that's how they get their nutrients.

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So, you know, a lot of plant life wouldn't occur if it wasn't for that integration with the fungus.

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Research has shown that over 90% of all plants, their roots are integrated with fungus for the supply of both moisture and minerals.

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When you walk through a forest you have to say, okay, which is more productive in terms of biomass per annum, the forest or the savanna?

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Everybody looks at this and they say it's got to be the forest because you're looking at a in this case of this forest a 30 meter high canopy and you've got all this three-dimensional biomass whereas on the savannah it's just grass that's that tall and that but you don't get the herds of animals here.

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So savannah produces more biomass, vegetative biomass

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per year.

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What you're looking at is accumulation here of centuries.

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But you are also in some of the poorest soils here and this is why the forests are so rich with fungi.

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It's the recycling, so it's the nutrients.

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So this is probably one of the best closed system examples and sustainable systems in the world is a forest because you don't have a lot coming in other than sunlight and rain and the rest is just recycling

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for centuries, millennia in fact, just because of the fungus.

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So you can extract humans, you can extract a whole lot of things, you need a couple of animals for seed distribution and they will just sustain themselves and carry on.

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And it's not this expansion process, it's just keep going.

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All driven by fungus.

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When I first met Mark for this guided forest walk, I was planning to make video content, but later I decided to change to a podcast format.

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So I reached out to him again.

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Mark has many scientific accolades and interests and is really, really generous with his knowledge about ecosystems.

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So we had a great conversation diving deep into the roles of fungi in the forest.

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Really excited today to be chatting with Mark Dixon.

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So Mark, would you like to introduce yourself and please share a little bit more about who you are and all of the interests that you hold in environmental education and sciences?

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Hi Jess, great to chat to you again and thank you very much for that intro.

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Yeah, so living in the Garden Roots, it really is a fantastic natural environment.

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So we're in the watershed

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of the Otonikwa Mountains and the Titsikama Mountains leading down to the Indian Ocean.

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We've got lakes, rivers, forests, spainboss, mountains and obviously some exquisite coastline and some great reefs.

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So it's something that just talks to my inquiring mind and I always want to know more about the ecological systems that are occurring.

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So I've always going investigating, checking them out.

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And this has sort of taken me into a path to complement my academic career.

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It's taken me into a path of actually having a business, taking people on guided nature walks and birding tours in the region and expanding through Southern Africa.

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So yes, one of the fascinations that this has led me to is just looking at fungi in the forest environment in particular, but in other habitats as well.

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I've just got to declare I'm not big on identifying them, but I like to know how they fit into the ecosystem and what ecological services that they perform for the, particularly the Afri-Montane forest, but other habitat systems as well.

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Yeah, those ecological services are specifically why I was excited to chat with you today, because I think in understanding how fungi work within an ecosystem, I think the more we can work towards public education and understanding fungi, interest in it, and ultimately that leads to more conservation or awareness or interest in the conservation

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of not only forest systems but also the fungi within them.

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So I'm very excited to learn about the ecological surfaces of fungi.

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We're going to talk a lot about that.

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But before we do, how did you get into all of this?

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What's your story?

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Well, into ecology, I mean, that all started at school.

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I wasn't a very sociable person and, you know, my escapism was getting into nature.

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So I would always be out and I'd, I'd see things and I'd, and I would want to know what it was, if there was a footprint, what had walked past and left that track behind and where plants fitted in, what role they had.

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You know, always interested.

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If I had a chance to get out into nature, I'd always take that, whether it was mountain biking, cycling or snorkeling or diving.

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And I just love travel as well.

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So I've been fortunate enough to travel extensively.

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And I always go into the natural environments and I look and I try to assess why a tree has a certain shape, what the function of that is or what the function is in the environment.

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You know, what's eating it, what it's eating, if it's, you know, animals and what it does to not get eaten, how it replicates itself and all that sort of thing.

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So, so those have always been the basis of my travels and my time in nature.

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Amazing.

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So it started off just with a sort of natural curiosity and has snowballed into projects and field research in marine sciences in projects such as your Strunt Looper project, which I believe researches the impact of lost and discarded fishing tackle on the reefs along the Garden Route, which is very, very interesting.

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Yes.

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and then also training and facilitation that you do or education in forest ecology, marine ecology, etc.

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It seems like you've got lots going on, lots of projects and all of them at the intersection of how everything works together.

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Is that right?

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You know, we've had too many specialists in the world and we've started to work in silos, so we're not connecting.

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And I'd like to have this broad overview of how everything is integrated.

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So, you know, in our Strontium project, the paradigm is ridge to reef.

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So what happens from the top of the watershed down to the reef?

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How does cutting down a section of forest have an impact on the reef ecology or a certain species of fish?

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I think we're very fortunate living here in that we've got a lot of archaeological evidence of changing sea levels and so the other project, the fossil footprints that I'm involved in

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looks at the Pleistocene era.

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So that's pretty much the last 500,000 years to narrow it down.

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And we've got the richest collection of Pleistocene fossil footprints in the world.

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But what is fascinating is that gives you an insight into the changing environments that we've had and the glacial time

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and how that has had an impact on the fauna and flora of the region.

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So some species going extinct, some species, their ranges changing and all temperature related.

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I know for a lot of my listeners who are interested in fungi, we are going to be thinking, wow, this has had an impact on the flora and the fauna.

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What about the fungi?

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So two questions for you.

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Do you know if there are any studies being done on the impact that all of this has had on the fungi of the region?

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And also, do fungi even show up in fossils?

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The answer is yes, there is someone doing research and yes, there is evidence of fungi in the past.

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you know, the iKnowledgee project that I'm involved in as a field researcher.

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We started with the obvious, so elephant tracks, human tracks, lion tracks, and all the megafaunas, both extant and extinct.

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But we are now moving into invertebrates.

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So now we know what the small animals are.

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You know, I think for me, if you look at forest ecology and the mycelium, which we'll get into, you know, that plays a major role and it gives you a concept of just the sheer timeframe that it took.

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you know, vegetation prior to the evolution of trees were very short because there was nothing to sustain and support anything over a certain height.

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And once you got cellulose and lignin, trees then could reach the massive heights that they do nowadays.

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The problem was that when they died and fell over, there was nothing that could decompose them.

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So they just then stacked up and over time trees just fell on top of trees and trees and you had this big layer of dead trees

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and then getting covered up by sediment and sand, and then fossilizing, giving us our coal seams.

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So that's where all our coal comes from, is all the trees that never decayed.

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And then after 60 million years, and this is quite a significant one to contemplate, after 60 million years, microorganisms evolved that could break down cellulose and lignin.

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And that was then the turning of the ecological system in that we would never have any coal formed ever again.

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and you had the reprocessing and the release of the minerals captured in the growth of the trees occurring from that.

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So, you know, the fungi have been there, microorganisms have always existed before any multicellular organisms.

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They're incredibly important.

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I think that the role that fungi play as a decayer or to break down plant matter is so, so interesting.

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And as you say, that's like a crucial role that it plays in an ecosystem.

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Could you describe how that plays out in a forest?

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So maybe using your local garden roots as an example.

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You know, to help put it in context, we've got to step back a little bit.

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So in the garden route here, we have 139 species of trees.

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Now, if we had to then quickly slingshot over to Canada and go to the boreal forest, there's only nine species of trees.

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So, and I'll give this as a context because you've got to understand this in terms of the fungi, because there's different roles that different fungi play in different regions on the planet.

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So the reason that you've got

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The smaller number of trees in Canada in the boreal forest compared to just this little pocket of forest we got here, which is 180,000 hectares, is that latitude is one of them and disease is the other driving factor.

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the high latitudes that the boreal forests of Canada and other forests at those latitudes have.

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You get this cold winter, comes through a sanitiser, so any microorganism or a pest will be sanitised as a population.

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So you've got to think of this in biological context.

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So in summer again, when things heat up, everything can carry on growing and there's not this species concern for an epidemic breaking out.

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and having a major impact on a population in a region.

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So what that allows is trees to grow super close together.

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So you might get one or two getting sick or infected or invaded by pests but it's not going to have a major impact on the population.

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As soon as you get closer to the equator though that changes.

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because you don't have that sanitation.

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So a pathogen or a pest population, depending on the temperature, can just continually grain until they get into an epidemic proportion.

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And so the world, since 2020 up till early 2022, was in lockdown and advocating social distancing.

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Forests have had social distancing for 60 million years.

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and it's part of their survival strategy, especially in the equatorial regions and the subtropics, because you want to be far enough from another member of your species so that if one of you was infected, not everybody got infected as a tree species.

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Okay, so the importance of this in terms of fungi is that the different ways that they interact with the trees.

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So you have this integrated mycelium of fungi in the forest and they're part of the process of breaking down and decomposing trees.

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So when you look at a tree dying, there's two processes that break it down.

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to recycle the nutrients that are captured in that.

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And so you've got a mechanical process which are things like earthworms, crickets, beetles and centipedes and they all will eat and chew their way through the wood and then their gut will inoculate whatever they've eaten and the fecal pellets that they pass with microorganisms which will carry on the process.

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So that's a mechanical breakdown.

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The chemical breakdown

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is a combination of microorganisms and fungi.

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And so the mycelium will envelop any organic material that falls down.

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So in this case, the trees and the vegetation.

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And it will then chemically process and break that down.

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And it's quite a slow process, especially when it comes to the trunks of the trees, the plants and the fruits and the leaves and all the smaller stuff goes a lot quicker.

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And that then contributes to building up the humus.

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And this is where it really gets exciting.

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That mycelium is integrated through the entire forest floor and

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you have intra and inter species connections.

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And within a species, you have a maternal to progeny connection.

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So any seedling that comes from a mother tree is connected by mycelium.

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And this is where the different latitudes play a major role.

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So if we go back to our Canadian forest as an example, the maternal tree will support and share resources with progeny.

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But as soon as you get close to the equator, the maternal tree will suppress the growth rate of a progeny.

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And for a very simple role, because if that seed, and this is in proximity to the maternal tree, so the further away from the maternal tree in the tropics, the less suppression there will be.

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But if it's very close,

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They have to suppress because you cannot have your progeny growing up right next to you and the potential of disease happening because then your genetic material will be eliminated.

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So you want to suppress until you die your progeny, seedlings, and then once you've died they can grow.

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If you're a short-lived species, if you're a long-lived species like our Podocarpus latifolius or Podocarpus folcatus, which are yellowwoods, they are long-lived, they can go up to a thousand years.

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Every tree, to be sustainable, this has to replicate itself once before it dies.

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Wow, like many others I'm sure you've heard of the term the wood wide web which has been popularized and unfortunately is also a little bit misleading but as it refers to trees sort of sharing resources via these intra and inter

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species connections and via mycelium.

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So I've seen mycelium described as the wood wide web in a lot of literature and I think a lot of that original literature was based on research work done in forests in the northern hemisphere, particularly in Europe.

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I don't know about the species diversity of those forests but how would the wood wide web work in South African climates?

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If you have a look at it, obviously there's the intra and interspecies connection.

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And then you've got some species that just don't connect at all.

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They're the loners.

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I mean, they'll connect to their own species, but they won't integrate with other species.

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So you have this collaboration within a forest through the wood wide web.

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And it is a term I like to use because obviously everybody's got the World Wide Web.

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And we do have a transmission rate, which is about four centimeters per second.

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So it is a system that will convey resources.

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So whether it's mineral resources, carbohydrates or water.

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So to give you an example, the trees lower down in the valley, closer to the streams and in the shaded areas will have access to more groundwater than the trees at the top of the slope.

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But the trees at the top of the slope will have more access to sunlight.

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So what you see is more photosynthesis occurring at the top of the slope, but there's not enough water.

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So through the mycelium, the resources are conveyed by the mycelium up to the top of the slope and carbohydrates are then conveyed down by the mycelium down to the trees lower down.

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So you have this sharing of resources and minerals and you get this

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relocation of minerals.

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And this is where it also gets fascinating is that as resources are extracted with the roots and the mycelium in an area that's got high concentration of certain minerals, that will then get transferred to area with low availability of minerals.

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You know, that's the benefit of that is that you've got mineral resource distribution and you've got recycling of a lot of organic material, whether it's a fecal content from an animal, a carcass of an animal or a tree that's fallen down or leaf litter or anything like that.

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And those resources are distributed through the forest, through the mycelium.

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I'd like to come back to something you said earlier about was it the yellowwoods who are actually limiting the amount of resources that they share with a neighboring seedling or tree of the same species.

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Are there other examples that you have relevant to your region that you can share of the role that fungi plays between trees or with plants?

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The role that fungi play within trees and plants.

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So you've got to remember that the mycelium is the communication systems between trees.

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You know, you've always got to bear in mind that trees don't have a central nervous system.

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They don't have a nervous system.

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and yet they seem to be able to function almost as if they're doing something cognitively.

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I think let's start off with a caterpillar chewing a leaf.

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This will give you context.

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It's a long way around, but you'll understand it better.

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So a caterpillar comes and chews a leaf.

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Okay.

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Trials have shown that a tree can identify the caterpillar from the saliva.

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So it's got a number of things that it can do.

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Has it ever been eaten by this caterpillar?

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If it has been, does it have a chemical

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that will repel this caterpillar.

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And it's not one individual caterpillar, you'll normally have a whole swarm of caterpillars coming in and attacking a particular plant.

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And we see a lot of that in this area.

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and for a reason.

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So what happens is, let's say it has had this species of caterpillar attack it in the past, it sends out pheromones.

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Okay, the pheromones have two functions.

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It then warns surrounding plants through pheromones that these caterpillars are in the region.

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They then start getting their chemical defenses against the caterpillars into place.

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What it also does is those pheromones waft through the forest and convey to predators of those caterpillars that there's

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caterpillars on this tree.

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So you will get a bird party coming and descending on that tree and then attacking the caterpillar.

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So they're now employing some assistance other than the chemical means of trying to repel it.

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That was the scenario that the plant has had that attack and it's got the chemical.

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If it doesn't have the chemical, it still sends out the pheromones, still attracts the predators.

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and sends the message down to the roots.

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And the request this time is, is there a chemical that will repel these caterpillar?

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And that will go out at four centimeters per second until it reaches a tree, whether it's a roost species or another species.

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So you've got this defense against pests, but it also happens with disease.

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Okay.

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So if we look at another species in the Afromontane forest down here in the garden root,

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it's the black witch hazel.

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So it's one of the understory species.

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Now they don't have spatial distancing, but what is interesting, they do frequently get a viral infection on their leaves.

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So you'll see leaves and they get these little noticeable markings on them, which is the viral infection.

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And they'll go through the whole process.

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Have they been infected before?

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Do they have the chemical to eliminate the viral infection?

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And the pheromones going out, down to the roots, out into the mycelium, and all of that.

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But what is fascinating is the next growth.

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So you only get it in one band of growth.

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And as it grows after that infection, all the new growth is healthy.

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Mark this is fascinating and I'm not a scientist so please excuse my absolute butchering of any of these concepts that you're sharing today.

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You've touched on three or four really crucial roles of fungi in the ecosystem from breaking down and decaying to create that layer of humus

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You've talked about mineral and resource distribution and sort of the sharing of resources.

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You've talked about the transmission of data, which is so cool.

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It's like trees talking to each other, you know, in service of protection, pruning, defense against pests and diseases.

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So, like, mushrooms are really cool.

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This is cool stuff.

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What role do fungi in insects play in the ecology?

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Okay, so the termites are interesting in that they can't digest and process cellulose and they are one of the few species that employ fungi to do that role for them.

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So they will have their fungal gardens in their termite mounds and they bring all their plant material down and they feed it into that and they then eat the fruiting bodies and the mycelium which have now got the nutrients and the carbohydrates from the process

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So they will inoculate their fungal garden and then they will maintain that.

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And that's an integral part of a termite mound's survival.

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Not only are fungi breaking down plants and all the other things as we mentioned, but they play this crucial role for certain insects.

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Are there macro fungi like mushrooms that pop up that are large and are crucial parts of the diet of maybe slugs or other animals?

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Well, I have seen slugs and snails eating mushrooms.

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I do harvest mushrooms and mainly the parasol mushrooms, just a bit of butter and garlic and they're really great.

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But if you've ever gone to harvest parasol mushrooms in particular, if you leave them too late, they have got a lot of little organisms, you know, invertebrates in there.

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I've never identified which invertebrates they are.

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You go and it looks like a lovely mushroom and you

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picket

(00:27:02):

Okay, fair enough, fair enough.

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And I totally relate to that experience of finding a beautiful like bolete somewhere in the forest and then you get all excited but you find that somebody else got there first and it might have been a squirrel or a baboon or a slug.

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But it's nice to know that we can share food with other animals and invertebrates.

(00:27:27):

Mark, we've covered a lot today and I'm so grateful because this is really helping to expand my personal knowledge on the role that fungi play and hopefully is educational for anyone listening to this.

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Let's talk very quickly about conservation as we start to wrap up the conversation.

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What are some of the challenges facing conservation of the garden roots natural ecosystems?

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I think population explosion is probably the biggest threat.

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So, you know, I, without giving my age away, in my lifetime, human population on this planet has more than trebled.

(00:28:07):

And in South Africa, we have more than tripled in the last 25 years.

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We've got a huge amount of regional migration, or as we call it in South Africa, semi-gration coming down to the coastal areas.

(00:28:21):

And so your natural resources with our high unemployment rates in South Africa, a lot of our natural resources are being exploited as a food resource.

(00:28:32):

And in the last five years,

(00:28:34):

We've monitored, particularly in the marine resources, a major impact on certain populations of certain species, which is of concern.

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When it comes to the forest side, there is a huge traditional medicine component in South Africa, and I think the whole of Africa.

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And we've seen, particularly the Western Cape, which has a massive influx of

(00:29:00):

African or indigenous populations coming from further north, down into the Western Cape, and certain resources being utilized for traditional medicine.

(00:29:09):

So using plants, herbs, geophytes, and those sort of things.

(00:29:13):

And I'm getting more and more inquiries to take people on nature walks to learn how to forage mushrooms in the forest.

(00:29:23):

And

(00:29:24):

it is something of concern in that the environment won't be able to sustain the demand if it's not done correctly.

(00:29:31):

And

(00:29:31):

You know, nature's phenomenal.

(00:29:33):

It will respond and reproduce exceptionally quickly.

(00:29:36):

The whole strategy, you look at things, sardines produce millions of eggs, abalone produce millions of eggs, spores, you know, prolific amount of spores from fungi and those sort of things.

(00:29:50):

But if you don't leave enough fruiting bodies out, if you don't do things in a ethical and sustainable manner,

(00:29:58):

If you're just harvesting and you think, well, I'm going to fill up this basket instead of this is what I'm going to eat tonight, we're going to get to a point where there's a decimation of a resource in an area.

(00:30:09):

And the consequences, if we take what the role of fungi are in a forested environment, the consequences of over-exploitation of fungi have major ramifications in the long-term in forest environments.

(00:30:23):

And you've got to look at what ecological services forests provide and water filtration is a huge component of that.

(00:30:31):

So if you start taking away

(00:30:34):

the health of a forest by eliminating or reducing the fungal, you've got a major problem with your water resources going forward, not only in the purification of the water resources, but just the water cycle in an area.

(00:30:48):

But I always remember there's an author, Lawrence van der Post, and he wrote extensively about the sand bushmen from the Kalahari and the Nama.

(00:30:57):

And he relates how traditionally, whatever resource it was,

(00:31:03):

and tubers, so they're hunter-gatherers traditionally, and they would only harvest and collect three out of every ten, so that there was always something left behind.

(00:31:14):

So the example I'd like to give is if there were 30 mushrooms, they would only take nine of them.

(00:31:20):

The next person that came along, there would be 21 mushrooms, they would only take the correct amount.

(00:31:26):

And so that you get to a point where you've got to leave mushrooms behind because you don't have the numbers.

(00:31:32):

So it's that leaving or only utilizing 30% of the resource that's there and leaving the rest for its natural processes.

(00:31:41):

That's the important thing.

(00:31:43):

I think that's really important and thank you for sharing.

(00:31:46):

Just to probe a little bit more on that, so if we're talking about harvesting fungi, of course there are thousands, millions of species within a forest and there will be a handful that are known as edible or medicinal and popular.

(00:32:01):

There are going to be lots and lots and lots of mushrooms.

(00:32:04):

Do you think it's ever possible to realistically actually exploit all of those

(00:32:10):

Fruiting Bodies in Such a Huge Forested Region.

(00:32:28):

a dry summer after a wet spring.

(00:32:32):

And it's fascinating, but all the Ganodermas in the forest died.

(00:32:36):

We're starting to get new Ganodermas now, but very few of the ones that died show any forms of re-grain or something like that.

(00:32:44):

I give that as an example because we have to be in context.

(00:32:47):

You know, in that year, for whatever reason that they all died, if it was climate change and that sort of thing,

(00:32:54):

excessively hot summer could have had an impact on some of these fruiting bodies and they're not re-emerging.

(00:33:02):

So if there was harvesting coincided with a factor, and I can't tell you what the factor was, I can only surmise that it was just the out of sync rainfall and the very hot summer period that we had.

(00:33:19):

So we're not going to get rid of it because the spores are always going to be there, but

(00:33:23):

We've got to be observant and cognizant of where we're harvesting and can the environment yield what we want for ourselves.

(00:33:32):

And we've got to say, are we doing this commercially or are we doing this for sustainable consumption?

(00:33:37):

And that's the most important thing.

(00:33:39):

And sustainable consumption is not to take back and fill up your fridge and then only eat one third and throw the rest away.

(00:33:45):

Sustainable consumption is to say, this is how much I'm going to eat.

(00:33:48):

Let me harvest that.

(00:33:49):

And I'll come back at another stage.

(00:33:52):

and

(00:34:07):

but you have to go out with that paradigm is that you're doing this sustainably.

(00:34:13):

I think we as particularly Western culture have got into the trap of you can go and buy a tomato every day of the year, you can buy a fresh lettuce every day of the year, you can buy a fresh strawberry, things that were seasonal you can buy any day of the year irrespective of where you live in Western society.

(00:34:34):

So we've got used to this concept of, if I like that, I want it every single day.

(00:34:39):

And so if we're going to be foraging, we've got to be seasonal, we've got to be sustainable and you've got to make sure that it's going to carry on.

(00:34:47):

I think the very nature is that there are a lot of spores, but remember the spores are saprophytic and as are the fungi, they need a resource to grow on.

(00:34:57):

So once again, you've then got to conserve to make sure you've got your mushrooms in your forest, you've got to have a forest.

(00:35:03):

You've just got to think in the broader context of everything.

(00:35:06):

Think again of the salmon going down the river, going out to the ocean and bringing the minerals back to get spread 250 kilometers into the forest.

(00:35:14):

So you've got to think, what is the consequence of me harvesting this down the line?

(00:35:18):

What are the trophy cascades that are being compromised, if they are going to be compromised, but impacted by my foraging activities?

(00:35:27):

I think it's super important because, you know, there is a lot of conversation and debate about foraging in the UK and in South Africa.

(00:35:36):

These are two of the areas that I've been looking at quite closely and of course I'm sure these debates are happening in other parts of the world as well.

(00:35:43):

And I think it's really important that we understand how to do it, as you say, responsibly and sustainably and with conservation in mind, with the future in mind.

(00:35:53):

And with that question in mind, I really liked how you phrased it when you said, can the environment actually yield what we want for ourselves?

(00:36:02):

So yeah, there may be a billion spores of this mushroom floating about, but if we continue harvesting without considering those impacts, maybe the environment won't be able to yield what we want for ourselves.

(00:36:17):

Sorry, just to add to that, so what we've got to look at, so we've been talking about beneficial fungi.

(00:36:24):

You've also got pathogenic fungi.

(00:36:27):

nature abhors a vacuum.

(00:36:29):

Okay.

(00:36:30):

So if you exclude certain saprophytic mushrooms, which are palatable and edible, the negative can come in and they, and you see that in cultivation, you may have to go and destroy a whole crop because it's just got infected with the wrong spores through your cleaning process and all of that.

(00:36:49):

So we've got to be careful of that circumstance and you know, that potential situation.

(00:36:56):

And that's why that sustainable harvesting of fruiting bodies and that is important.

(00:37:02):

I know when I go to get paracels I'll take my three out of every ten mushrooms out of the fairy ring.

(00:37:08):

I want to know that I'm going to be able to harvest and there's lots of fairy rings where I live so I'm very fortunate.

(00:37:15):

In the South African context, there's very few people that 1. want to forage and 2. have the courage to forage.

(00:37:22):

Everyone's petrified of misidentification and picking the poisonous mushroom.

(00:37:30):

You know, as I say, there's more and more people wanting to do foraging, do something, you know, the medicinal components, the nutritional components, and I'm talking in South African context.

(00:37:42):

Traditionally, we've just gone for, you know, the cultivated mushrooms and just the stock standard button mushrooms.

(00:37:49):

but more and more we're getting your saprophytics, your exotic mushrooms as they market it here and people are learning that well you can go and forage these as well and you know that's very difficult to over harvest but it's not impossible depending on how many of the population decide that that's what they're going to do.

(00:38:10):

Thank you.

(00:38:11):

One more question on conservation.

(00:38:14):

We've touched on how important it is to have a mindset of conservation and particularly when you are foraging, whether plants or fungi.

(00:38:22):

I love that kind of rule of three out of ten.

(00:38:26):

I think that's lovely and it's easy to remember and something that people can easily adopt into their habits.

(00:38:32):

What about the conservation of non-edible fungi, all the other types of fungi in the forest that are pretty to look at, or sometimes we can't even see with the naked eye, that are providing all these beneficial roles?

(00:38:46):

Does that come down to the actual conservation of the forest itself?

(00:38:51):

Yeah, it comes down to the conservation of the forest and it comes down to conserving the environmental factors that are favorable to those organisms.

(00:39:01):

The irony is they could probably expand if there's over-utilization of the edible mushrooms.

(00:39:08):

You know, habitat destruction is the biggest threat.

(00:39:11):

Running with Mushrooms

(00:39:28):

But it comes down to environment and everything's got a reproductive strategy and some need a particular critical mass to function as a species in terms of reproduction.

(00:39:41):

And in terms of fungi, they need a resource.

(00:39:44):

Thank you so much.

(00:39:45):

It's been fascinating learning about the role of fungi and how we can think about protecting fungi and its habitats and as it plays such an important role in larger ecosystems.

(00:39:56):

So Mark, thank you so much for sharing all of your knowledge today and it's been wonderful chatting with you.

(00:40:03):

No, it's a pleasure, Jess.

(00:40:04):

And I mean, it's great catching up with you again.

(00:40:06):

And I mean, you've done some wonderful things on the realm of mushrooms.

(00:40:10):

And yeah, I think I've got to really commend you on your exploration on what you've done here.

(00:40:16):

And, you know, just raising the awareness of the spectrum of what fungi are in the context of the planet, really, because that's what you're doing.

(00:40:26):

You know, you're looking at the human content, you're looking at the ecological aspects

(00:40:30):

And that's, yeah, well done and glad I could be part of that and share a little bit of knowledge that I have.

(00:40:36):

Thank you.

(00:40:37):

Thank you.

(00:40:38):

To wrap up, if listeners to this podcast would like to find you and your work online, where's the best place to go?

(00:40:45):

Well, I've got two points of contact.

(00:40:48):

So for marine research, there's strontloperproject.org.

(00:40:54):

For the nature guided tours, there's gardenroutetrail.co.za.

(00:40:59):

Wonderful.

(00:40:59):

And it was through gardenroottrail.co.za that I found you and had a wonderful walk.

(00:41:04):

So I would encourage anyone listening to sign up.

(00:41:07):

It's a great day out and you can learn not only about fungi, but about lots of other parts of the garden root.

(00:41:14):

Great.

(00:41:15):

Mark, chat to you soon.

(00:41:16):

Thank you so much.

(00:41:17):

Okay.

(00:41:18):

Cheers.

(00:41:21):

Running with Mushrooms is an independent research project.

(00:41:25):

Our producer, research director and host is Jess Jorgensen.

(00:41:29):

Check out runningwithmushrooms.com for more episodes, as well as blog posts about the tour and articles diving into my micro cultural insights.

(00:41:38):

In the show notes, you'll find links to reach out, subscribe and support my guests.

(00:41:42):

I hope that you're inspired to geek out about mushrooms with me and thank you for joining the mushroom tour.