Homegrown National Park

Lukas: Where did you like to play as a child? I ask this question a lot because childhood memories shape us into the people we become. Welcome to Play It Forward, a Wearthy podcast. I'm your host Lukas Ritson. Thanks so much for joining me. I talk a lot about play — I'm a dad, I'm a husband, I'm an educator, and I'm a playground designer. So I want to gather some of my favorite people who are advocates of children and nature and create a space to have an honest conversation about getting more kids outside. The power of play is very often underestimated, and I think we all need a little more play in our lives.

Our next guest wants you to create a Homegrown National Park, and it's not as daunting as it sounds. Our philosophy at Wearthy is creating environments for children to thrive, so who better to have on the show than someone that researches thriving environments as a profession.

My next guest is a professor at the Department of Entomology and Wildlife Ecology at the University of Delaware. He has authored around 100 research papers and has taught insect-related courses for 40 years. His book Nature's Best Hope was a New York Times bestseller. So a big warm welcome, all the way from Delaware, 6pm at night, dedicated to the cause — Doug Tallamy. Thanks so much for joining us.

Doug: Well, thanks for the invitation. Pleasure to be here.

Lukas: I'm so excited to chat to you and break down the roles and just bringing the awareness to ecology for our listeners, be it if they're educators trying to convey the importance of environment to children. And also I love the fact that you're promoting people to just take action on this topic that seems so daunting for so many. And you can get less lost in this politicalization of ecosystems and environment. So I love the fact that it's like, "Hey, you do you, you bring it home — literally." How did you land on that as an action point?

Doug: Well, you know, we have a global biodiversity crisis which gets worse every day. But it's a global crisis with a grassroots solution. It's going to take good earth stewardship by everybody. But you know, that makes sense — everybody on the planet requires a healthy ecosystem. So why wouldn't everybody have the responsibility of good earth stewardship?

You know, right now we have a few specialists, a few ecologists, a few conservation biologists, and they're supposed to take care of the earth. Everybody else has a green light to destroy it. That makes no sense.

Lukas: Yeah, so the ratio is a touch out on that one. Because we're framing up as a bit of an introductory deduction to ecology, can you give that definition to our listeners? Like, okay, what are these guys on about? What is ecology?

Doug: Ecology is the study of how plants and animals interact with their physical environment. Anything with an "ology" in the end is the study of. And entomology — same thing, the study of insects.

Lukas: Excellent. And when you say — what was the other phrase just then thrown in? Biodiversity. Some people might not know what biodiversity is as well.

Doug: It's all of the life forms on the planet. Now you can divide that in many different ways. Typically we're talking about species — the number of species that are out there. But you can talk about genetic diversity, you can talk about ecosystem diversity. But it's the diversity of life forms, and again, typically we measure that in terms of the number of species that are there.

Lukas: And this is an example of how keen I am to get into this topic — I haven't even asked you the question that we ask all guests and how we start: where did you like to play as a child? It's a question we start with, but I was just so keen to get going on this topic we skipped over it.

Doug: Yeah, somebody asked me that this morning too. How did I get interested in this? I was born interested in other living things. I tell the story of moving into a new house in third grade, and there was a little pond next door. I used to go visit that every day, see what was happening in the pond. And you know, there were toads there breeding and all the little pollywogs swimming around. And I was there the day those pollywogs matured — they were hatching, they were hopping out onto the land. But that was the day the bulldozer came and buried the whole pond. I don't think he even saw me sitting there, so he didn't bury me. But you know, right then that made an impression on me — we need to work on our relationship with the living things on planet Earth. But I was always attracted to nature right from the start.

Lukas: And you touched on it there — do you think children are born natural environmentalists, if you will? This innate response to care for the thing that we're a part of, and it's just bred out of us? Or what's happened?

Doug: You know, I have a brother and a sister. They were in the exact same environment as me, and they're just not into this. They — I'll say they don't really care. It's not that they don't care, but it's not a passionate response to the environment the way I have. So I would say you are kind of born that way. It's not that they lost it — they never had it. And I think that's pretty typical.

Most people — I mean, E.O. Wilson talks about biophilia, how we all naturally like nature. And on some level we do. But boy, we spend an awful lot of time destroying it for a species that loves it. So not sure I buy into that.

Lukas: And how have we got here? Because we lived synergistically within environment at some point, and we were a part of it. And now we consider nature as the thing over there and us. So what happened to create that divide?

Doug: We are products of nature. We've always depended on it. But it also was our enemy. You know, the predators were out there hunting us, the drought was killing our crops, and we would drown in floods. And the people that controlled nature were the ones that survived. So that has been part of our background. And we're, of course, very good at controlling nature — we're controlling it to the point where we've eliminated it.

But it has led to this idea that humans are here and nature is someplace else. Yeah, which, you know, if there's just a few humans on the planet, that'll work. But with 7.9 billion people, I guess it doesn't work at all. There is no someplace else for nature. And what we are not appreciating is the extent to which we need functioning ecosystems — not just in parks and preserves, but everywhere. And so that's why we're in the sixth great extinction, because we don't have functioning ecosystems everywhere. We've pushed them out to the corners of the planet, and it's not enough.

Lukas: And you mentioned there the sixth extinction. It really frames up how urgent this situation is. So do you want to break that down — what's the sixth extinction?

Doug: Well, Earth has experienced five mass extinctions prior to this, when asteroids hit and we have massive volcanic action. And they still debate what causes these things. But you know, right from the start we've had these giant extinction events where it eliminates 80 to 90 percent of the life on the planet. The last big one was when the asteroid hit 66 million years ago.

But now we're doing the same thing. And this is the first extinction event caused by a living being, a species — and that's us. Why is that a problem? People say, "Well, extinction is normal." Yeah, it is. But not at the rate at which we're causing it. When we had those mass extinctions, it took millions of years to rebuild the diversity that created a healthy functioning planet.

And by functioning, I'm talking about creating the life support systems that we humans demand, that everything demands — not just us. We call them ecosystem services. And we know from lots of research that the more species in an ecosystem, the more stable it is and the more productive it is. So with 7.8 billion people on the planet, we need more ecosystem services now than ever before. But we're taking species out of ecosystems, we're degrading them, so we're actually getting fewer and fewer all the time.

And that's just from a selfish perspective — that's why extinction is just not such a good idea. And it doesn't have to be global extinction. Local extinction still ruins the ecosystem that you are depending on locally. So we need vibrant ecosystems everywhere.

Lukas: And then it actually impacts our lives as well. Although we can manhandle it — for example, near me there's beautiful bushland, kangaroos, sunrise and sunset driving down the road I'd always look for the roos there. Bulldozers come in, bulldoze the whole thing down. And then the people that live there that have just destroyed all the biodiversity, that ecosystem that was there — they've just clear-cut this whole environment. So I just imagine when the houses go in and the lawn goes in, it's just going to be these barren wastelands of environment which are actually just going to impact our health. Like the temperature — just a slight change in temperature is going to impact the bodies and then impact health due to those temperature changes. The lack of the microbiome, of that diversity, of those beneficial interactions with nature — okay, avoid those, and then we wonder why we get sick and tired and frustrated and anxious. It's just perplexing to me.

Doug: And the reason you can live in an environment like that, at least temporarily, is because we're bringing in resources from places where we haven't wrecked the ecosystem. But when we do that everywhere, you know, we're talking about colonizing Mars. Good luck. Take everything. We can't look after this one. The Earth — we know this one works. But boy, yeah.

Lukas: A frightening statistic in your book was that 54% of America — and you consider America having this great expanse of nature — 54% is what is called an urban matrix. It was classified as within an urban, suburban matrix.

Doug: Yeah, I mean you can drive down the road, there are little patches of woods here and there, but they are far too small to sustain the species that actually run an ecosystem. Yeah, you can appreciate that when you get up in a plane and you fly — then you get to see how chopped up the environment really is.

So we've got 48% of the country is in agriculture, and the other 54% is in this suburban urban matrix. And then you get 5% that's relatively pristine. That's not enough. And those are typically the mountaintops and places that are — you know, the only reason we left them is because we can't live there.

Lukas: The other positive thing which I like about America's practice is you've got public land for national parks, which is great. Can you break that down — what that means?

Doug: We do have these national parks and preserves and monuments. And you know, this was largely Teddy Roosevelt's idea a hundred years ago — we want to preserve these places because they're magnificent, and we want future generations to be able to appreciate them. And they are magnificent, and it's been great.

But there's two problems. One is it suggests that nature is there just for entertainment — we want to go see them and be entertained. It is entertaining, but we need nature so that we have future generations, not just so that we can be entertained.

And it's very obvious that these parks and preserves are not working as intended, because we are in the sixth great extinction. We're losing species. In North America, we've lost 3 billion birds in the last 50 years. That's a third of our breeding bird population. If our parks and preserves were enough to sustain the species that we need to run our ecosystems, that wouldn't be happening.

So these are great places, but we now need to practice conservation outside of parks and preserves. And that's where this Homegrown National Park idea comes in. It's got to happen in your yard, it's got to happen in your corporate landscape, it's got to happen in agriculture.

Lukas: And I love what you kind of just mentioned in passing then, but it was a really big aha moment for me — that nature's being used for entertainment, not seen as a place for... And I'm guilty of it. I'm thinking about, "Oh yeah, I've just gone and done all this entertainment recently going up to the Daintree Rainforest." And yeah, that's a big mind shift. It's like, why are we considering entertainment when it's integral for our overall wellbeing and existence?

Doug: There's nothing wrong with being entertained by nature and appreciating it. But if you think that's all it's there for, that makes it not essential. And if it's not essential, when resources are in short supply and push comes to shove, then nature takes a back seat. And that, of course, is what happens all the time. Resources are always in short supply.

And you know, the budget — the national budget to run the national park system is under a line item called "non-essential items." Wow. So if we run out of money, we just — it doesn't matter. Nature is essential. It's not optional. And that's the missing link here.

Lukas: Yeah, absolutely. And so we've spoken about this — the urgency around it from a really big scale of like impact on a whole country and from a world standpoint. How do you get that to your backyard or your playground in your front yard? Don't forget.

Doug: Yeah, no. Well, there are four things that every landscape has to accomplish. It's got to support a viable food web so that there are other species around, because that's what's running our ecosystems. It's got to support pollinators, because they're pollinating 80% of all plants and 90% of all flowering plants. So people say, "Well, you need them for agriculture." You need them to pollinate all those plants or we lose them.

It's got to sequester carbon — these days we got to pull carbon out of the atmosphere and pump it into the ground and build plant tissues. That's what plants are doing. And every landscape has to be landscaped in a way that manages the watershed in which it lies. That has to happen everywhere.

And if you look at your yard and say, "Am I supporting pollinators? Am I supporting a food web? Am I managing the watershed properly?" — if you have acres of lawn, you are not. And "Am I using plants to sequester carbon the best?" And again, lawn's the worst choice in that regard.

So that's what brings it home to the personal landowner. Because if you're going to have the audacity to say, "I own part of the Earth," there's a responsibility that comes with that. You have to be a good steward of that piece of the Earth. Don't worry about the whole planet — just your piece. And that requires a lot of things. It requires shrinking the lawn, getting rid of your invasive species, putting in pollinators, and using keystone plants. Lots of very important things.

Lukas: There's so many avenues I want to go down right now. Let's start with this one. You've mentioned food web. Traditionally in schools, we're talking about the food chain — it's all about the food chain. But I love the fact that getting to know ecology in your work specifically and the reference of a food web, as opposed to a food chain, just that perception that things are non-lineal, things go out or things go sideways as well as up and down. Can you break down what's the main difference between a food web and a food chain?

Doug: If anything is linear and it's very simplified, where you have a plant, one thing eats it, then one thing eats that, and one thing eats that — that would be a linear chain. That's not the way life is.

So for example, in my yard I have oak trees. Well, I also have 511 species of caterpillars that eat those oak trees in my yard. So that's one tree, one genus, that has 511 lines coming out of it. And then all the predators and parasitoids of each one of those caterpillars — that's why it builds this spiderweb type of interactions. It's just a more accurate way of describing it. But it's the same principle as a food chain — it's just that it's more accurate to what's really happening.

So when you take out that oak from your yard, you've destroyed an entire web of life, not just one thing that's going to eat it.

Lukas: Yeah. And that's what you're talking about — a keystone species?

Doug: That's a keystone species. People have compared native plants to non-native plants for a long time now. And on average, native plants certainly support more life than the non-natives. But we've discovered that just 5% of our native plants are supporting 75% of the energy that supports those food webs. 14% of our native plants are supporting 90% of the energy that supports that food web.

Which means 85% of the native plant species that are out there are contributing, but not all that much. So I talk about keystone plants. You remember the Roman arch — the keystone is the stone at the top of the arch, and if you take that stone out, the arch falls down. So if you take these really important, hyperproductive species out of the food web, the food web collapses — even if you have dozens of other species, they're not those really productive ones.

So I talk to people and say, you know, you're building an ecological house in your yard. The keystone plants are the two-by-fours of the house — they're holding it up. They're not the only thing your house is built out of, but they're essential or your house is going to fall down. You don't build a house out of wallpaper.

Lukas: Yep. So that's the role of keystone plants — there's something that's got to be there, and then you can diversify around there.

Doug: Something I think comes to mind is like we've got keystone behaviors — like certain people, you're saying only such a small percentage contribute 80%. You've got such a small percentage of people having keystone behaviors that are so integral to their environments and communities and habits, going out and doing the community gardens and all of that stuff. That's awesome.

Lukas: Awesome. So where do people start? Like, we talk about ecology and keystone species — what's the first step for people? Just imagine they've got a — they're trying to teach a child about environment and ecology, because our default is to say, "Hey, we're going to go compost, hey, we're going to go recycle. I'll teach you about environment — you've got to recycle." And that's great. But how should people ignite this passion for children to understand environment?

Doug: Children seem to inherently like animals. But you can start by explaining, well, what do those animals eat? And they can say, "Well, they eat food." Where's the food come from? And what builds the food? And you're going to get back to plants.

Most kids don't inherently like plants very much. But they are that first trophic level that's essential, because they're the only things capturing energy from the sun and turning it into food. So all the animals that the kids like depend on plants at one level or another. Either they eat the plant directly, or they eat something that ate the plant, or they eat something that ate the something that ate the plant. But it all started with the plant.

And so the real learning moment here for the kids is that not all plants pass on their energy equally. If the plant captures the energy but doesn't let anybody else use it, what good is it? It's not going to help us. So this is where plant choice comes in.

You know, your Australians have given us eucalyptus. Boy, do we use that all around the planet. It's great in Australia, but it's terrible every place else because it doesn't support the life that it does in Australia.

Lukas: Yeah, it was remarkable going — where was I? San Diego. And even San Diego, I was like, "What are all these gum trees doing here?" They just seem so out of place.

Doug: You're near the Baja Peninsula and you've got a gum tree. You're like, what is it? Yeah.

Lukas: And that brings us to another point — people might not understand the importance of native species versus non-native species. So can you break that down? Because we at Wearthy really prioritize natives. We pride ourselves on building play environments with completely native species. And Dan, our landscape architect, and Nikki, his assistant, they come up with plant tiles to create diversity in ecology within like a meter by meter square, and then they can roll those out across environments. And they've got different tiles for different environments, which is super exciting. But why is that important from an ecology standpoint to have natives?

Doug: Because natives are willing to pass on their energy. And by willing, I mean — most vertebrates don't eat plants directly. They eat an invertebrate that ate the plant. So we're talking about really the interaction between the plant and the insects that are eating that plant. The insects gather the energy from the plant and then other things eat those insects.

Well, plants don't want to be eaten. So they protect their tissues in a number of ways, but typically with nasty-tasting chemicals. So the only insects that can eat a particular plant are the ones that have adapted to those particular nasty chemicals. And in order to do that, it specialized — they get really good at getting around particular groups of chemicals. But that locks them into eating the plants that make those chemicals. And when you're locked into eating this plant, you can't eat this one over here. That's called host plant specialization.

But that period of adaptation happens when the plant and the insect are interacting with each other over long periods of time. So that's why the native plants are supporting the native insects far better than the non-native plants, where our native insects have never seen them before and they haven't had that period of adaptation. And if you think adaptation happens in a few years, it doesn't. It's thousands of years, if then.

And what happens in the meantime? So we have the monarch butterfly — everybody wants to save the monarch butterfly. Well, it's a specialist on milkweed. If you take milkweed away, it doesn't start to adapt to crepe myrtle — it dies. And then it's gone. And that's that.

So that's why native plants are so important — they're the plants that have supported these co-evolutionary interactions over long periods of time.

Lukas: Yeah. Do you think we've forgotten what normal is? Like, normal as a child was walking through the grass or walking just through your lawn and having grasshoppers jump and hit your legs. And being outside and catching heaps of grasshoppers from everywhere. Now I go to do it with my children and it's like — nothing.

Doug: Yeah, where are they? That's a prime example of what we're talking about.

We — my stepson got married, well, it's been a while now, in Tennessee. We went to the wedding in Tennessee, and the day before the wedding, we went and took a hike in a natural area. And one of the people in the wedding party there is from Tennessee. The entire understory was Amur honeysuckle, bush honeysuckle from China. And it was in bloom. And she's walking around, she said, "Isn't it beautiful?"

I said, "Well, yeah, but these are non-native plants and they're not supporting anything."

She said, "What do you mean non-native? They've been here the whole time I've been alive on planet Earth."

So yeah, they have been. But you know, that was only 25 years. And that's not very long. And so to her, that was normal. But it wasn't normal. It wasn't even yesterday. She had never experienced normal.

Lukas: It's frightening to think. And another statistic — and I'm probably wrong, my retention on data — 90-95% of vegetation in America is present with non-native species?

Doug: No, we measured the plants that are used in suburban habitats — three states. And it was, first of all, 92% lawn, which is a non-native plant. But it was 80% non-native ornamental plants that were used in these habitats. We've got 3,300 species of introduced plants that are considered invasive. An invasive plant is one that's displacing native plant communities. 3,300 species — that's a lot of species.

Lukas: Yeah. And that has a trickle-on effect that people always need to remind themselves of. That — yeah, it's not supporting a host plant of an insect. You might not care about the insect, but you're going to start caring when it's impacting your food supply.

Doug: Well, you know, a lot of people do care about birds. The charismatic megafauna of these days. So think of the insects as bird food. It takes thousands of caterpillars — 6,000 to 9,000 caterpillars to make one clutch of chickadees, which is a little bird, a third of an ounce. 6,000 to 9,000 caterpillars just to get them to the point where they leave the nest.

So if you load the environment with non-native plants that aren't making any caterpillars, you've devastated the ability of that chickadee — that single pair — to reproduce. It's one of the major reasons we've had the loss of 3 billion birds in the last 50 years.

Lukas: Yeah. It's frightening. So where do we go from this point? Like, we've got — we're coming up against this machine in modern times about climate change and it being politicized. And it's like kind of a policy that's adopted by certain political parties. So, you know, you're out. How do we get around that to get people connected and see it as their own choice?

Doug: You know, I've been talking about this for close to 15 years now. And fortunately, this particular environmental issue has not been politicized. So people from both sides of the aisle are upset that we're losing our birds. They're upset that we're losing our insects, which surprised me — I didn't think they'd care.

And what I'm saying is you can do something about this. And that makes them happy. They want a solution here. When I say you fix the piece of land that you own, or if you don't own land, help somebody who does, help a park or preserve — then you're contributing to the solution. And they get into that, they like that.

So there's nothing — you know, everybody on the planet requires a healthy environment regardless of your political parties. You really have to stretch. Of course, you could say the same thing for climate change. But yeah, this is an issue that is going on regardless of climate change, which is why — climate change is very serious, a lot of people talking about it. I try to stay away from it a little bit because this is a problem independent of climate change.

Lukas: Yeah, due to our impact and our own habits over time. Not so much that biggest scale. Over the last 40 years of studying this topic, what's the standard observations you've made about community perception and uptake in that time?

Doug: Well, I actually haven't been working on this for — I started around year 2000. So let's call it 20 years. I have been pleasantly surprised at the response. I thought the horticultural trade was going to clobber me. And, you know, I wrote "Bringing Nature Home" but I didn't think anybody would read it. But they did. And they're interested in solving these issues.

So the change has happened a lot faster than I thought it would. We are talking about changing culture. We're talking about changing our relationship with the natural world from an adversarial one to a collaborative one. And changing culture is hard — it doesn't happen overnight. But it is happening. And I've been very pleased with the rate at which it's happening.

Lukas: So do you think we can regain that status of identifying as environment, as opposed to it being over there and us being us?

Doug: I think we're better. You know, we do better. You know, we have one planet and we humans take over the entire planet and expect the natural world that supports us to be someplace else. That's not going to work. The logic is so obvious. I really do — it's hard for me to believe that we're not going to catch on here.

Of course, the real challenge that nobody talks about is the number of people. We cannot continue to increase our population forever and expect any of this to work. The planet is not growing. So we can increase our population at the same rate the planet's growing, which is not very fast.

Lukas: There's talk about the population plateauing at 10 billion. Is there any reason in your understanding that's realistic or not?

Doug: I don't think it is. We are already three times over the carrying capacity for humans. So now you're talking about adding another 3 billion on top of that and expecting everything to be fine. We've got this extinction crisis because we're taking all the resources that support the life forms that support us.

So saying, "Well, with no other outside effects, we'll stabilize at 10 billion" — there are outside effects. We call it war, disease, famine — all the things that are at least passively associated with environmental degradation. And that's just going to get worse at an alarming rate as we add more and more people to the planet. We're not adding — see, the more people that are there, the more we degrade the carrying capacity, the ability of the Earth to support us.

Lukas: Yeah, it's kind of like — we talk about invasive species, and it's kind of like we've taken the role of invasive species.

Doug: We are the biggest invasive species, for sure.

Lukas: Oh, it's a sad state of affairs. How do you stay optimistic? You start talking about extinction crisis and percentages of nature not present — these are hard things to talk about. So how do you stay optimistic?

Doug: You know, I get emails every day from people who are doing what I'm suggesting — working on their property. They send me pictures. I've seen it on my own property. You know, we moved into a piece of a farm that had been mowed for hay. It was just about nothing here.

Four years ago, I decided to take a picture of every species of moth that is now making a living on our property because we put the plants back. And I'm up to 1,123 species of just moths — haven't gotten to the butterflies yet.

So this all tells me it works. You know, we're not making it up here. You really can put life back. When the World Wildlife Fund says we've lost two-thirds of our wildlife, I say not at my house. So if I can say that, so can you. So can everybody else. And that's what makes me optimistic.

Lukas: Yeah. I'm excited because we've recently acquired a block of land in a rural area — 5,000 square meters with a creek. It's half grass at the moment. So I'm really excited about creating that ecosystem. There's platypus in the creek.

Doug: Really!

Lukas: So yeah. So it's going to — yeah, I'm super excited about creating that and bringing it up into the property and even creating more diversity. Because I go around and explore that creek and it seems pretty — there is a lot of native species because there's an environmental protection covenant. So invasive species, you have to remove them, which is great. But there's still not much there. So I'd like to improve on that.

Doug: Yeah, absolutely. It's going to be a life's work, I think. And I have something to aspire to — I've got to hit the 1,000 moths mark.

Lukas: An integral part of how this food web works is these relationships. And it once again paints a picture for us to understand a very complex idea — that we have producers and consumers within that web. And it doesn't mean you have to be one or the other, because at some stage you're both, as my understanding — my very novice understanding — is we can — we are both at some stage of our life. Some species are, yeah?

Doug: Yeah. So how do we — I think my observation is humans have become a primary consumer role in this web. So how do we get to that producer role?

Yeah, we certainly have. We eat very high on the food chain, on the food web. We love our meat. The number of cattle on the planet is a major environmental issue in terms of producing greenhouse gases, in terms of the amount of water that it takes. And that's because we insist on eating beef. So if we ate lower on the food chain, then that would help very much.

We're never going to be producers because the real producers are plants. But we get to choose which plants and how many we put around us. So we can boost the productivity of the land that we control with proper plant choice and proper plant maintenance.

Lukas: Yeah. And also our own waste distribution is — I see that as one of the things we can manage as well. Not only our bodily waste management, but the impact we're having with our microplastics and things like that. So we're not — the only thing we're producing a lot of the time is damage, unfortunately.

Doug: Unfortunately, yeah. You know, it's hard because each one of us sees a very small part of the planet each day. And it's very difficult for us to imagine that times 7.9 billion. So we look — you know, we use our plastic bags and we eat our steak, and it doesn't seem that bad for us as an individual. But when you multiply that — that's what's hard for us to envision. And that's where the problem lies.

Lukas: Yeah. And to get a bit morbid, for all of the consuming we do throughout our lives, once we end up in the ground, we're contributing very little from a nutrient standpoint to that ecosystem.

Doug: Yeah, especially the way we do it — we embalm ourselves to make sure nothing returns.

Lukas: Yeah, absolutely. So where to next for you in your mission? Within publication, research — what books next?

Doug: Well, I get email — email is my nemesis. I get emails all day long, and most of them are questions. And a lot of them are repeated questions. And I could ignore them, but, you know, the public is interested in learning how to do this stuff. So I'm really seriously considering a book where I answered these questions. And I said, here's the major questions on different topics, and this is the answer. Don't email me anymore.

The next big piece of research, though — the reason we discovered the best difference between keystone plants and the rest was that we ranked their ability to support caterpillars across every county in the country. And that was based on the literature of the last hundred years. It was a big job. We've done it for North America.

But it turned out to be a really powerful tool. I want to do that for all the countries in the world where the literature exists. It's going to be tough in parts of South America and Africa. But certainly through Europe, Australia — you've got great records of what eats what. And I can say, here's a list — these are the best plants that you should be putting in different parts of where you live. And then nobody has an excuse. They don't have to —

I mean, Portugal, most of Portugal's forests is eucalyptus. And they can say, "Well, we didn't know this wasn't a forest." Well, now you know. Here's a list telling you what eucalyptus is supporting in Portugal — which is nothing.

Lukas: So that's a big piece of ignorance that I'd like to solve before I retire. Apologies on behalf of Australia for the rest of the world with eucalyptus. Because it's pointless.

And the audiobook has the back chapter of the Q&A, which I really love about your book as well. One question that stood out to me was someone asking, you know, "If one invasive species in a whole ecosystem, could it be really that bad for it?" And to which your response was something along the lines of, "Well, if you've only got one tumor in your body, is that bad for it?"

Doug: That's right. These species are tumors. They grow all the time. It doesn't stay one. And that's the insidious nature of an invasive species. And it's not — this vegetation in our natural areas is from China right now. Wow. Because they've escaped our gardens. And they continue to spread. You know, another 10 years, they'll be a quarter — or half — who knows what.

Lukas: Yeah. It's like in my reticular activation system to see invasive species now. I think my wife is tired of me driving along the road and pointing something out. I was like, "This!" Oh, Singapore — we went to actually look at a property to buy, and it was half-covered in Singapore daisy. And I was like, "No way."

Doug: Beautiful property. But that gives you a goal. You can say, "I'm going to fix this."

Lukas: Perhaps. Yeah, that's one way to look at it. But then I just thought, I have no family time. I would spend my life doing this. Singapore daisy — it was like through a valley. There was so much of it. And I'm just like, "That's daunting."

And to extend on that point, like — I like how you say the one plant, one invasive species isn't the problem. It's the growth of that species. And the existing ecosystem can't keep up with that rate of evolution to be competitive anymore.

Doug: When you look at some of the major invasive species we have — like kudzu, I think it covers 20 million acres. It's measured in millions. Privet, millions more acres. Bush honeysuckle, millions more acres covered in these plants. That's only three species, but they're covering half the United States.

Lukas: And the cause of a lot of the California fires, as my understanding, is — was it creek grass or cheatgrass?

Doug: Cheatgrass. Brought in for cattle. And it's nice and green in the spring, but then it senesces and turns into tinder through most of the season. And these fires start outside of the forest and then they run in through cheatgrass right into the forest. And the smallest thing can set it off — a lightning strike, somebody's cigarette. And the whole West — hundreds of millions of acres are covered with cheatgrass.

Lukas: Yeah. And another disservice we do — through reading your book — is not letting the natural burn-off process happen within these huge big forest areas. Hence they burn — not just do a little grass fire under the understory and burn the grasses off. You were mentioning how it jumps to the canopy then.

Doug: So obviously, two years ago we suffered from some of the worst bushfires in recent memory in New South Wales. So interesting point. Well, then you know what it's like. But yeah, we've had a hundred years of fire suppression. So during that time, fuel has built up. So when you get a fire, it's a huge fire. And it's not a ground fire — it jumps to the canopy, kills the trees. And that's devastating to that particular ecosystem. And most of our fires, particularly in the West now, are canopy fires.

Lukas: And I saw that devastation firsthand. I like going down to those communities and trying to help. And still you can see the severity. Everyone sees so many of the trees sprouting new growth and saying, "Look, it just bounces back." But that's in certain areas. There's some that the burning is so severe and so hot, there's nothing growing back still — years later. It's just a field of toothpicks. And where's that life going to happen now?

Doug: Which is scary about the koalas. I don't know how many koalas you lost.

Lukas: Yeah. Speak time. So is there going to be a Q&A book next? I would love that. Sign me up.

Doug: Yeah. I say that — I haven't had a second to write any of it. But that's what I'm thinking at this point.

Lukas: And for our listeners, I would love for you to like and share this podcast. And we will run a competition and give away some of your books, because I think it's just so integral. And also, where can people find out more about what you do, and if they want to learn more about ecology and entomology?

Doug: We have our website, homegrownnationalpark.org. And a lot of information on that website about what I've done and about the organization. You know, we have the map — get yourself on the map, become part of Homegrown National Park, and tell us how much area you're going to plant in natives. So that's another thing we'd like to expand — to other countries. We could start in Australia.

Lukas: Absolutely. We'll do it. We'll be planting that playground by playground. We'll log it. We'll get it international.

Doug: Good.

Lukas: Good. Well, thank you so much for joining us today. Thanks for contributing so much for my learning. And sure, my listeners' interests have been sparked in this such an integral topic and field of study. So from me personally, thank you for all the work you do. Thank you for an amazing book as well. I've read one, I'm on to the next two. I'm excited. But thanks so much for joining us today.

Doug: Well, thanks for the opportunity.