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0:00
Good morning. My name is Tasker Alfred. I'm a associate professor of department landscape architecture here in Mississippi State, and it's wonderful to see a forum. I see a lot of people you saw last night. We had a great crowd out last night. I do want to go ahead and bring some people again, just so you know where
0:19
you've been helping what's been going on. But this is the Michael and Rebecca Boganlecture series. We got a very generous gift from them to help foster a little lecture series. Here. We're very appreciative of that. I want to thank the Far Department who have been very supportive and
0:39
our lecture community Corey Gallo these here this morning or not.
0:45
Tim, Schowalker and Peter, someone with your own committee with me Bob. Bob Dusek who is
0:53
here, someone who helped tremendously getting word out to provide you guys that this will be going on
1:00
here Karen Brasher to help us get people set up here for reporting for our website that you like to see this as well. And we'll get back information after this. And the state of chapter ASLA a bunch of you guys are here. Thank you for all your hard work. You do the word out and they're going to have to have some some lunch for quite a while and talk with them for a few minutes after. This will be in our gallery across the way. So I'm very thankful for them to put this all downtown.
1:35
New to Baker, professor of entomology and wildlife ecology, and he's a professor of art science department in Berkeley as
1:45
he's the author of Nature's Best Hope and Nature. Love to bring you a culinary perspective on the main plant
1:54
this morning. The lecture is going to be coming for you. A little things that run the world. We'll go ahead and get started to help you in welcoming Dr. Phil Collins a pleasure to be here this morning. I will point out that the chairman of our Entomology Wildlife Ecology Department is Jake Bowman, who graduated from this this school and wildlife. He he worked on black bears and he came to Delaware. And we said not too many black bears here,
2:21
although one did run through campus a couple of years ago. And I called up Jake. I said, Jake, this is your chance. He switched to box turtles. But
2:31
okay, so last night we talked about, you know, my idea of nature's best hope you and I are at nature's best hope. And we talked about some generalities in terms of of the future of conservation. It's really everybody's responsibility to say we're going to we're going to drill down a little bit more in terms of the role of insects in rebuilding functional ecosystems and human dominated landscapes. So in order to do that, I've got to do a little bit of overlap with what we talked about last night.
3:00
And one of the overlapping features would be E.O. Wilson, because that is his expression right there, the little things that run the world and of course, he is a Harvard emeritus at the university at Harvard University.
3:18
His entire career And he died the day after Christmas. So it's a tremendous, tremendous loss to conservation. We have to I mean, he wrote an awful lot. We should read every single word of it, because I never knew him to actually be wrong. So one of the things he wrote early on this in 1987 was this paper, the little things that run the world and it sets the stage for for this talk His message in that paper was that life as we know it on planet Earth depends on insects.
3:46
And that's because they do so many critically important things Most flowering plants depend on the pollination from insects if insects disappeared so at our flowering plants. So in 90% of our flowering plants and that would so drastically change energy flow through our terrestrial ecosystems that the food webs that support our animals or amphibians are reptiles are birds or mammals freshwater fishes. This would birds with collapse and all those animals would disappear.
4:12
The biosphere, the living portion of the earth would rot because we would have lost insect decomposers that that rapidly turn over nutrients and all we would have is as bacteria and fungi. And of course the important thing is that humans wouldn't survive any of those drastic changes. So it was a sober, somber message, but this was 1987 and nobody was afraid of insects disappearing. As a matter of fact, we spent a whole lot more time trying to kill them all everywhere.
4:40
And besides, if we're worried about insects, why do we have National Insect Killing Week?
4:45
Now this was 1929, so it was a while ago, but it was a campaign to boost the sales of all brands of chemicals to rid the community of insects, not pests, all insects. We're just going to kill them all
4:58
So we don't have national insect killing week anymore, but it's still very much part of our culture. Let's face it, every time we see an insect, in most cases we do go out of our way to kill them. And even if we kill them all in agriculture and we understand they're competing with our food there and even if we kill them all at home, just because we have intimate phobia and we don't like them,
5:18
we still think they're they're doing well because they're doing fine in our natural areas. There's two reasons why that's not true anymore. One of them is we don't have enough natural areas anymore. We have turned those natural areas that supported insects into our cities, and they're not designed to support insects into our suburbs. And they're not designed to support anything
5:39
into our rural areas. You know, you drive through the, quote, rural areas. They're still not designed to support insects. Then, of course, we have agriculture got a lot of agriculture. 770 million acres of rangeland in the US. That's four and a half times the size of Texas. It's dedicated to cattle, and most of it, unfortunately, is overgrazed, and it certainly is not designed to support insects. As a matter of fact, food production on planet Earth now occupies almost half of terrestrial earth,
6:08
and that's not designed to support insects. The second reason that our natural areas are not supporting insects, the way they used to is that just about everywhere and I mean just about everywhere. They're heavily invaded with plants from other continents. We call them invasive species. This is what a natural area near me looks like. This is White Clay Creek State Park. And this is what it looks like in.
6:31
Well, right about now, in March, when plants from Asia leaf out before plants from North America. So every bit of green you see there is a non-native plant in this protected area.
6:42
When when we have measured, it's about a third of the vegetation in this entire protected area is is from Asia. And these plants are not designed to support insects and with North American insects. We'll talk about why that is in a few minutes. So non-native plants wherever they're spreading or where they're we putting them intentionally are very poor at supporting insects and they're replacing the native species that are good at doing that. We have 3300 species of non-native plants
7:11
that are considered invasive in this this country. That's a lot. Now, when I was young, sites like this were commonplace. And you hear about this all the time. Nobody measured it so we can't give you any any numbers. But when you drove, you had insects splattered on your windshield. I remember my grandmother having grill guards. She lived in Florida to protect the grill from all the insects that get splattered. We don't see that anymore when you look up at it at a streetlight.
7:41
I don't see that anywhere. Maybe you do in Mississippi. I hope you do. But there's nothing flying around this, the streetlight. So it's anecdotal, but it really does make people feel, at least as old timers, that insects have been disappearing. So there's lots of evidence now that we are winning our war against insects, our undeclared war against insects. And now we're seeing headlines that support that the insect apocalypse is here. What does it mean for the rest of life on earth
8:05
talking about global insect decline that people are starting to measure? You know, we noticed that there were problems with honeybees several years ago with colony collapse disorder. The colonies were not making it through the winter anymore, and everybody wondered why. So people started to look at bees at least in this country. Here's some stats from from bumblebees. 50% of our well, 50% are native bees. All the species have disappeared from their historic ranges.
8:32
In the last century, there are four species of bumblebees that have declined 96% in the last 20 years. Now, that means they're not extinct yet. So they're not in any list that's part of definition, where you take common insects and you make them uncommon,
8:47
but they're functionally extinct. They are no longer performing their role in their ecosystems. And there are three species of bumblebees that may actually already be extinct. 25% of our bumblebee species at risk of extinction. So, you know, they're not they're not doing well in Europe. Insects are doing poorly. 30% of Europe's worth options the grasshoppers, the katydids and the crickets are facing extinction. Right now.
9:12
Great Britain, they love their their Lepidoptera, their models and butterflies. They measure it all the time. So there's lots of statistics about declines in Britain. Three quarters of their butterflies are in steep decline. The V moth is decline. 99%. Well, that's a list of things that are that are in trouble. This is a study that really kicked it off several years ago.
9:34
A long term study started in 1989 and Germany documented a 79% loss of flying insects since 1989. There are 46 species of moss and butterflies that have already disappeared from from Germany. And then invertebrate abundance and we're really talking about insects here has declined 45% on planet Earth since 1974 and that's a 2014 statistic so it hasn't gotten any better since then. We really do have an awful lot of data that the little things that run the world are disappearing
10:12
And of course as insects decline, the things that require them, the things that depend on them are declining as well. And we measure birds better than anything else because people like birds But I want to, I want to stress as a whole lot of other things that depend on insects as well. We got 432 species of North American birds that are now threatened with extinction according to the State of the Birds Report. What does that mean? It doesn't mean there's only five left of each one of them.
10:36
It means that the the trajectory of their populations over time is is decreasing so rapidly. That's exactly what the passenger pigeon did. Passenger pigeon used to be the most common bird on the planet and gone entirely. So we recognize now that steep declines are just the signal of impending extinction, even if they're still a number of them left. We've lost 3 billion breeding birds in North America in the last 50 years. That's that's from Rosenberg at all.
11:07
And I mentioned this last night, but it's worth going over. We we went to the dataset of that 3 billion bird that's a Smithsonian study
11:15
using the breeding bird atlas data and divided the terrestrial bird species into two groups. There's the bird species that depend on insects, particularly when they're breeding, and the bird species that really don't depend on insects. They're seed eaters and they can rear their young on seeds. So things like finches and doves, and they didn't decline at all in the last 50 years. The demands that can make it on seeds are doing fine. But the birds that require insects
11:41
have lost, on average, 10 million individuals per species. So it doesn't prove cause and effect, but it certainly does suggest that as you take away bird food, the birds aren't doing very well.
11:52
You know, we have English sparrow and we have starling. Serious invasive species not just in this country, but all over the world, came from from England, came from Europe. Really. We brought them over. We didn't come. Well, now in England, English has sterilize their landscapes so much that both these species are red listed. You can't find them anymore because there's nothing for them to eat over there. So these are just indications that things are not doing well.
12:17
And that's why we see this statistic. 1 million species are facing extinction, according to the U.N., and they're predicting they're probably going to disappear in the next 20 years. Most of the species will be insects, by the way.
12:31
And as I said last night, that's a statistic that we've got to turn around.
12:36
We can't tolerate a million species disappearing because these are the little things that run the world and support us. So if we want to be happy, we've got to start protecting them. And that's the question. Does all of this matter? Well, the creatures that that keep us alive are disappearing. So it does matter. But how do we convince people of that? That's hard. You know, we humans do not react to long term. What we consider to be long term risks. And long term is two or three days from now.
13:04
You know, if it's not happening right now, we tend to ignore it. But we're pretty good at feeling paternal, maternal, empathetic towards other species. We want to take care of them. So I'm trying to take advantage of that. That feeling by looking at insect decline through the eyes of a bird. I want you to be this bird now. This is a Magnolia Warbler. I want you to pretend you are this Magnolia Warbler. And right now you are undergoing the most dangerous thing
13:34
you're going to do in your entire life. And that is migrating you have just over wintered in the Talon making mountains of Costa Rica, and it is time for you to fly north so you can reproduce people as they fly home. Well, actually, they only spent a few months north to spend most of their time in the tropics. So our North American birds really are South American birds.
13:53
But it is a dangerous undertaking. There are lots of of predators that depend on migrants. They've got to fly across the Gulf. Somebody looked in the stomachs of tiger sharks during spring migration a couple of years ago. They're filled with migrating birds that don't make it. They just fall into the ocean. So there's a lot of risk there. It's it's energetically expand they lose 35% of their body weight with that single, single flight across the ocean.
14:21
And once they hit the land, they continue to fly. They do stopover points but every time they fly, they can go up to 300 miles and they lose a lot of a lot of body weight. 35 to 50% of their body weight, which means when they stop, when they come down to rest. It's not about resting. It's about eating. It's about putting that body weight back on. So they have energy to continue their migration. Many of these birds, particularly the Warblers, are going all the way to Canada
14:51
and they don't fly around us humans anymore. They don't fly around our cities, they go right straight up the way they always used to. And when they come down, they have got to eat. They've got to put that body weight back on or that's the end of the migration. So migration is tough. If it's tough, why did it evolve? That's a good question. But migration evolved for the same reason that anything evolves. The advantages outweighed the costs.
15:18
The costs are steep, but the advantages were even better. What are the benefits of migrating? Well, of course, in the temperate zone, throughout the temperate zone, all our deciduous plants leave out and following that big flush of vegetation comes the flush of the caterpillars that eat that vegetation. And that is what supports the migrating birds. It's what supports breeding once they get here. And that flush of food doesn't happen in most areas of the tropics,
15:47
the tropics are much more constant. There's a tremendous amount of competition down there. So you have this this bonanza of resources just north of the tropics. And some birds figured out that if I fly north, I've got more to eat.
16:02
And if I've got more to eat, I can make more babies. If I stay in the tropics, I can I can make two to four offspring per year. If I fly north, on average, I can make three to six. And these are vast averages over hundreds of species. But that advantage in reproduction was enough to counter the disadvantages in
16:23
migration. Its increased reproduction. So bird migration was adaptive, but only because there were so many insects available in the temperate zone. It would never have happened if there if there hadn't been. How many insects are we talking about? Somebody actually measured that in 20. 18. I have no idea how they measured it, but they estimated that birds eat 500 million tons of insects on planet Earth each year.
16:50
And they, they this was a paper in, I think it was in science and they, they use the same approach that we always have. That means birds are good at eating all of our pests. Remember all insects or pests. We got to kill them. So the birds are helping us do that. Let's rephrase that and say birds require 500 million tons of insects just to be birds. And if you reduce that amount of insect food you're going to reduce the amount of birds that are available.
17:17
So when migration evolved, there were plenty of insects in the temperate zone. Is that still true? Do we have enough insects to support this very dangerous behavior that is now ingrained in birds? They're going to migrate whether they don't know there's not enough insects up here anymore. And the answer is, every time we we go to measure it, no, there's not enough insects anymore. So let's just focus on the impact of introducing plants on on the insect populations.
17:43
That the birds are depending on. So here I've got great myrtle. Y'all know, crape myrtle drove by a bunch of I'm coming into the university here. I think it's the the state
17:53
tree in South Carolina. And I don't think it really is, but there's a lot of them. So I'm not just you know, I'm not just talking about ornamentals here. I'm talking about the non-native invasives, too. And by the way, 85% of our woody invasive plants are escapees from from our garden. So they're often the same plants. We've actually we've been measuring this, I don't know, less 15 years. So we got a lot of studies. But this is this is why it was published just recently just went out
18:23
with an undergrad to hedgerows that were heavily invaded with the invasives near University of Delaware. So that's Autumn Olive and multi Flora Rose. And are you on a bittersweet and and bush honeysuckle and Japanese honeysuckle and on and on and that's what most hedgerows look like. And we measured caterpillars in a standardized way in those hedgerows and compared the hedgerows that were not invaded with with none is the real trick was finding uninvited hedgerows
18:48
that was that was tough but we did find a couple and we found there was a 68% reduction in the number of species of caterpillars in those those hedgerows
18:59
a 91% reduction in the abundance of those caterpillars. And here's the big one a 96% reduction in the biomass the actual amount of energy available for the birds to eat in those invaded hedgerows. So when we have a plant invasion, you're taking away bird food. You're taking away almost all of the bird food. And you know what happens to the birds in your backyard? When you don't feel your bird feeder? They go away. Birds need food. They're not going to reproduce.
19:28
And all of these areas that are that are totally invaded and that means they're not going to be able to migrate through them either.
19:35
We're not talking about just a few birds here. We're talking about 386 species of neotropical migrants. That may no longer have enough insects to justify their migration. The stats, the swallows and the swifts are Orioles. Our hummingbirds are various by the way. Hummingbirds say, well, they feed sugar water.
19:54
They do eat sugar water. But what is it? 80 to 90% of a hummingbird diet when they're reproducing is insects and spiders. You don't make a bird out of sugar water. You need you need protein, varios, ten injuries. They all reproduce on insects, bunting, is flycatchers. Our thrushes are warblers. All the species of warblers are depending on insects. And again, as I said last night, it's mostly caterpillars that they're depending on, not just any old insect.
20:22
And of course, our resident birds that don't migrate also depend on these these insects. Yes, they're eating seeds during the winter. Time in part. But when they're reproducing, they take thousands of caterpillars to actually pull off a nest. This is data from chickadees. 6009 thousand caterpillars to get the birds to the point where they fledge. Parents continue to feed them caterpillars. Another 21 days after that, you're talking about tens of thousands of caterpillars to make a bird.
20:50
That's a third of an ounce, but that's not an exception. There's data from seven or eight species where people have sat there and counted all the caterpillars coming in, both here and in Europe. Thousands to make out are birds.
21:04
So what if I said introduce plants are reducing your bank account by 96%.
21:09
You would immediately get the significance of that
21:13
because we had this idea that we live off of our our bank accounts but really the it's the insects that are the currency and our ecological bank account. So if we've lost 96% of them under certain circumstances, this is something we need to be alarmed about. It is our ecological bank account that keeps us alive in the long run.
21:34
So I think our only viable option is to is to learn how to live in harmony with the natural world that sustains us or learn how to live sustainably. We use that word all the time. What's the option? The other option, unsustainable. That doesn't last very long. So this is really it's you know, I often say I specialize in the obvious. I mean, these these things are so obvious, I don't even know why we're talking about them. And all right. How are we going to do that?
22:07
I've also been talking about focusing on private property. We have parks and we have preserves. The two small the two isolated from each other. We now have to do conservation on private property. Well, how much property is privately owned? Most of it, 85.6% of the land east of the Mississippi is privately owned. 78% of the entire country. 98% of Texas 95% of Maine. A lot of private property out there. We have to do conservation on it. And this is what a lot of it looks like.
22:34
Took that picture from a helicopter here, not not far from where I live. It's a beautiful lawn. Here's a guy mowing it. But all the plants there are non-natives. This is our this is our baseline. Here. This is what we're starting with. How are we going to save insects in a landscape like that? Well, first, let's look at the causes of insect declines. David Wagner wrote a Now, it's actually quite a famous paper talking about the causes of insect decline.
23:00
And his his summary is it's death by a thousand cuts. There's so many things that are clobbering them
23:06
but these are the big ones, the misuse and overuse of pesticides. Notice, I'm not saying all pesticides, pesticides are appropriate at appropriate times, but we tend to go crazy with them. Habitat loss, whatever that means. You know, what you're taking away with? The habitat, by the way, is not just a place to live. It's not just a place to hide. That's what most people think. It's the food you need to eat to. That's habitat.
23:31
And when we decrease the amount of food, that's habitat loss and it's plant choice. It's our choices of plants and our landscapes that are hitting that habitat, creating a habitat loss quite a bit, and also creating the invasive species that we're talking about. Now, I'm talking about invasive plants, but we also have invasive insects. I recognize that we don't want them either. Light pollution is turning out to be a huge cause of insect decline. And of course, climate change is a big one,
23:58
mostly in terms of the highly erratic climate we're having, the terrible droughts in the West, the California, New Mexico, Arizona region is I heard the other day people say it's it's the worst drought since the thirties. It's the worst drought in the last 13,000 years.
24:17
It's a big one and it's clobbering the plants and the insects out there. But good news here all of these are easily addressed by each one of us in this room. We can go home and we can we can stop using our pesticides. We can start fixing our habitats. We can choose the right plants. We can we can turn out our lights at night and we can get rid of the invasive species on our property. Those are things we can all do and really help this. I'm not going to assign fixing climate change
24:46
yet. But, you know, this is a this is a policy thing. You actually can influence that by how you vote. But we we're not going to go there. All right. So we have to raise the bar about about what we expect our landscapes to do. This is another house down the street for me. This guy has a nice lawn he really does.
25:05
But in the past, we have asked our landscapes to be pretty. That's all been about esthetics. So we go to the nursery, we buy something. It's that's a decoration Maybe it could be a screen or anchor, a focal point, but it's all been about how pretty we can make our landscapes look. And we're good at that. No thought about the ecological role that these plants need to be playing on private properties. It is it is a new idea.
25:29
But when plants are just decorations and we use them, that way, we make beautiful landscapes. But that's ecological destruction. That is not a functioning ecosystem. We could make pretty plants that are creating ecosystem services that support food webs. That's a huge one. Without the pants plants passing on their energy, you don't have any animals or protecting our watersheds. They're doing lots of things, supporting the natural enemies, helping pollinators.
25:55
And when we include ecological function in the criteria that we're basing our plant choice on, then landscaping equals ecosystem restoration.
26:07
This is 21st century landscaping, folks. We've done 20th century landscaping and we're in the sixth grade extinction. So let's give 21st century landscaping a chance and see what happens.
26:19
All right. What does this have to do with insect declines or restoring insects? We can't restore ecosystems without restoring insect populations. It's it's that simple. So how are we going to do that? Which insects should we be making
26:34
There are a lot of insects out there. There are three to four species, million species of insects worldwide. Three to four. We're not sure because we've only described a little bit more than 1 million species. So most of the insects that are out there are still undescribed and there are many species that will disappear before they ever get described
26:53
We've got 164,000 described species in the US, but I can still regularly collect moss in my yard that are not described yet. We call them new species, no name on them. So there's still a lot of work to do, but it's, it's a lot of species. We're not going to, we're not going to protect all of those in each one of our our yards. So which one should we focus on?
27:16
I think there's two main groups that we really need to do focus on the insects that maintain plant diversity plants are the first trophic level. That means they are capturing the energy from the sun and turning it into food. And all of life on terrestrial earth depends on that food. Well, the plants that maintain are the insects that maintain those plants have got to be important. Then we have to to to support the insects that are helping move the energy from those plants to animals.
27:46
Those are the two most important groups. And we're talking about the pollinators, of course, but we're also talking about caterpillars.
27:53
So who says these are the two most important groups? I do. And I'm giving this talk
28:00
somebody is going to argue with me somewhere, but we'll have that argument later.
28:04
Okay, let's let's talk about pollinators. I'm not going to spend a lot of time on pollinators. There's been an awful lot of talk about finally, we're recognizing the importance of pollinators. And this is only an hour talk, so we can't spend a lot of time on it this. But it should be recognized that flower
28:22
call it out. That's Virginia Creeper. There's small, inconspicuous flowers, but they are magnets for the native bees. Okay. Just some basics here. Why do we need pollinators? You can hear everywhere every day that we need pollinators because they pollinate a third of our crops. May Berenbaum, the chairman of the entomology department at Illinois, she is so E.O. is dead, but May's not. And she's got to be the next best entomologist in the country. Maybe the world.
28:54
She looked at that figure, trying to figure out where it came from. And she can't find where it came from. It's one of these urban legends. Her best calculation is that it are the bees support one seventh of our diets. If we have a healthy diet. But our typical diet, which is depending on wheat and corn, both wind pollinated it's really about one 12th of our diet is is supported by pollinators. So the the agriculture argument for having pollinators around doesn't
29:28
hold up very well for me, and it doesn't hold up for a lot of people if they don't live next to a farm. They say, well, I don't live next to France, so I don't need any pollinators. And if that's the only reason we talk about pollinators, being important, I don't blame them. But of course, that's not true. We need pollinators because they're pollinating 80% of all our plants and 90% of all flowering plants. If we lost our pollinators, we'd lose 80 to 90% of the plants on our planet,
29:51
including our crops. But there are other important plants out there that really are. So losing our pollinators is simply not an option. We talk about good land stewardship. How about talking about essential land stewardship? It is not an option to lose the pollinators so we have to do it. All right. That's it. So we're talking about pollinators. Now let's talk about caterpillars there. They're fun. Yeah. And most of the caterpillars we're talking about are our moths.
30:19
For every species of butterfly, there are 19 species of moss. And, you know, the group that's doing the best work with moths it's the month photographer's group right here in this campus. If you don't know them, go say hi there.
30:33
They're leading the way. All right, caterpillars. They are the bread and butter of terrestrial food webs. Again, little, little appreciated fact, but they are eating the plants and then other things eat them. And that's why we have other things. If we don't have caterpillars, we we have failed food webs.
30:51
And then Jansson way back in 1988 says caterpillars transfer more energy from plants to other animals than any other type of insects. Landscapes without a lot of caterpillars are dead landscapes. It's that simple.
31:03
So how do we increase the number of caterpillars in our yards? Well, you add caterpillars to your landscapes by adding the plants that make them, which which seems easy. But there is a catch and that is that most plants don't make a lot of caterpillars. This is elderberry. It's a wonderful pollinator plant. Makes wonderful berries for the birds. It makes zero or one caterpillar. I mean, almost no species of caterpillars. Eat our elderberry doesn't make it a bad plant.
31:27
But you can't build a landscape out of elderberry only if you want to have enough caterpillars to support breeding birds. So we have to be fussy about our plant trees, and we have to be fussy about it because the caterpillars themselves are fussy and they're fussy because plants have made them fussy. Plants don't want to be eaten they want to capture the energy from the sun and and use it for their own growth and reproduction. So they loaded the leaves with nasty tasting chemicals
31:52
that makes these plants either bitter or downright toxic. And it's true for all the plants that are out there, not our agricultural plants, not our lettuce. Why not? Because we've bred it out. We've read out those defenses which is why many of our egg crops have so many insect pests. They don't have their defenses anymore. They're highly transform plants.
32:12
But it's a defense that works really well. And it keeps most of the insects of the world from eating most of the plants of the world. And that's why it's green in the summertime. It's because not because there's no insects out there. They want to eat those plants. It's because most of the insects that are out there cannot eat most of the plants. They are too well-protected. But we do know that insect plants. So how do they do that? How do they get around this chemical defenses?
32:35
Well, this is where specialization comes in. 90% of the insects eat plants are what we call host plant specialists. They can only eat the particular plants that they have developed ways of getting around, of circumventing those plants defenses. They develop specialized enzymes that store and excrete and detoxify. This compounds specialized behavioral adaptations and life history adaptations that allow them to avoid contact with this compound. Compounds.
33:03
You know, monarch butterflies are specialists on milkweeds. Milkweeds are toxic plants. And we know that they can eat those plants without being poisoned by the cardiac glycosides in there. But what about the milky latex sap that's in there? It gums up caterpillar mouthparts, glues them shot. So how does a monarch eat it? That's another talk. But they snipped the mid rib of the of the vein of the leaf before they they start to eat. It cuts off the flow of the latex sap.
33:31
So then they can go down and eat the rest of the of the leaf. That's a behavioral adaptation that protects them from a very effective defense. It keeps most of the other insects off of milkweeds.
33:43
So that's what allows these insects to eat these plants. But since every plant is protecting itself with a different cocktail of chemicals, fences, the insect can only adapt to a couple of them, maybe even one. And that means they're locked into eating those particular plants so monarchs can eat milkweeds any of the milkweeds. But if you take milkweeds out of your yard, the monarch can't eat your hosta. You can't switch over to something else. It's locked in to what it specialized on.
34:13
So plant choice matters. If I want to have the beautiful Pandora space at my house, I need Virginia Creeper. If I want the tulip tree moss to the trees, silk moss I need tulip tree. I mean, that makes sense. Linamar is now looms as their 25 genera of plants recorded as host plants for lunar Mars. But locally at my house they eat one sweet gum. Locally, they're specialists
34:38
zebra swallowtail everywhere. It's only a specialist on pop. If you don't have papa, you don't have any zebra swallowtail. I think that's the prettiest swallowtail in the country. Grapes, native grapes are really productive plants. They support things like the spotted forest or moss and many others. The Green Marvel on by Burnham who wouldn't want the green marvel
34:57
brown hooded outlet on Golden Rod go there and supports 110 species of caterpillars at my house. At my house. I don't know how many here, but a lot a lot even things like poison ivy beautiful you Tilly is a specialist on poison ivy.
35:12
You know when you get poison ivy, when you try to take it out, leave it alone. It won't chase you down the driveway. The best defense against poison ivy is to learn what it looks like and just. Just don't touch it. So it supports the beautiful utility of every other. Several other miles makes a very valuable berries for the birds in the fall. High and fat. That's what they need. But there's. There's specialization everywhere. Persimmons support the sculptured moss, black gum,
35:39
the Hebrew are pure ashes. You guys don't have the word yet, do you?
35:45
We do. And there's a number of big Sphinx moths that depend on ash I think that's art in the garden, by the way. Rosy maple moth on maple. Beautiful moth. This is the royal walnut moth and walnut and hickory it's already extirpated from New England. That's the largest by weight loss in the country. So these things are disappearing. We can't allow that to happen w.th prominent on on even witch Hazel has specialists like the Witch Hazel Dagger Moth, Imperial Moth and Pine Native Clematis supports
36:20
the spotted cypress, but the non-native doesn't
36:24
ironwood it supports it to turn and sell us button. Bush gives us the last outlet, the Herald is on native Willis Snow Berry Clearing on coral honeysuckle. The evening primrose moth, believe it or not, is an evening primrose and it spends a day with its head stuffed in flowers like that. It's very cute. Our prettiest emerald butterfly is on sumac. And I don't mean poison sumac I mean staghorn. Sumac are smooth sumac, wonderful landscape plants
36:49
every time I hear what we had to bring in Guatemala destabilized the soil. We had to plant kudzu, destabilize the soil, sumac stabilizes the soil really, really well. And it gives us this in many other important insects. And we get some real powerhouses, things like the our native prune us. So where I am, it's it's black cherry, but American plum Chickasaw plum
37:11
will give us things like the the white circular, the crocus geometry of the US. The Secretary emboss the colorful easily the tufted bird dropping moth boy talk about the green marble. Who wouldn't want the tufted bird dropping moth
37:25
the paddle dagger moth petal caterpillar? This is a learning event for your kids. Tell your kids to go out in the yard and find a paddle caterpillar and figure out what those paddles are for. They're not decorations. They have a function it's the same function that the filament geometry has these expandable filaments. They go out and they go in and don't tell them the answer. Let them figure it out themselves. And I'm not going to tell you the answer either. I want you to think about it.
37:52
The small lights, banks, all these guys are in black. Cherry Harris is three spot. It has an umbrella of its shed head capsules over its head. And when you come by it, it'll a wacky with it. It doesn't want you there
38:04
then. Oh, so you're still the most productive plant we have in this country. Will give us things like the hag moss, the red washed prominent, the white dotted prominent, the spiny caterpillar, the Swiss moss, the white blotch head, or a camp of the oak skeletonized to the solitary oak leaf miner, the orange patch, smoky wing half oval, and still as the crown slug. These guys are called slugs because their head is tucked underneath, not because they're really slugs.
38:29
The pink striped bookworm, my favorite, the spun glass slug and hundreds more. We talked about this last night, the concept of keystone plants how just a few plants are making most of that caterpillar food that drives our food webs and lead the way. Remember what a keystone is? It's a stone in the middle of an arch. The Roman arch. If you take that stone out of the arch, the arch collapses. Well, if you take Keystone plants out of your local food webs, the food webs collapse.
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Just 5% of our native plants are making 75% of the caterpillar food that drives us food webs. 14% of our native plants are making 90% of the caterpillar food that drives our food webs.
39:06
So in what county are we in? Is this Harrison County
39:14
It's close. I'm sure it's close to 400 species of caterpillars on oaks in Harrison County. And it's very they're very typical for all the counties next to each other, very similar. 950 species of caterpillars nationwide on an oak oaks are the top keystone plant in 84% of the counties in which they they occur
39:36
what again goes to produce. We've seen some gringos today walking around zero caterpillars and Kinko's. It's a beautiful plant. But if it's the only plant in your landscape, when those birds migrate through, they will come down and look for food and there won't be any.
39:51
And if it's really at the end of its rope, it's physiological rope that could be the end of the of the migration for that that bird. So think of the Keystone plants as the two by forests in the ecological house that you're building. They're essential to build to hold up that house. You can't build a house out of wallpaper. And that's what we've been trying to do for for the last hundred years. You're not through building your house
40:13
once you have these Keystone plants but they're an essential component of it. So what do you how do you find out what the Keystone plants are for where you live? You go to Native Plant Finder, her National Wildlife Federation website, and this is the one I did it just right. These these so you get a rank list of the woody and non-native of the woody and herbaceous plants plant genera in your county that are producing the most caterpillars and the list much bigger than this I just
40:37
ran out of room.
40:39
So now you have a very good feel for which plants you should be focusing on where where you live,
40:45
where to take all the pictures I just showed you, I took them at my house and that's what our house looked like when we moved in. It was part of a farm that was broken up into a ten acre lot, mowed for hay before we moved in. So what really came back were all invasive species and very few woody plants at at all. But I put many of the plants back, not all of them. I've been counting the number of species of Mars. Those, those those runners have food webs and I'm up to 1000, 140 species so far.
41:16
But every time I get serious about it, I add more species. So I don't know what the total is. And this is just moss having gotten the butterflies yet. And they are there because we put the plants back, we put witch hazel and oaks and persimmons and everything on that list and many more. And we tolerated these guys. They come in on their own black cherry. People say, Black here is a weed. Why is it a weed? Because it grew on its own.
41:40
It's a it's a top keystone plant. Ferns and wonderful grand covers, native grapes, you know, really, really high tulip trees, just native plants, very a lot oaks, hundreds of species, about two or three support. 21. It's a good native plant, but it's not a keystone plant. Anyway, we tolerated all these guys, including poison ivy, including green Bayer, including Dodder and other things that I haven't thought of. And that's why we have all those mines and because we have all those mothers
42:09
and all those caterpillars. We've got breeding birds that can now make a living at our house. We've got wood thrush. Remember that bare ground with us is a forest bird, la trees, the acorns I planted 20 years ago and now 60 feet tall. Wood thrush says this is a good forest and it didn't take that long. And it's there because it can feed its babies. The Lettered Spanks which is produced by Virginia Creeper. We've got Indigo Bunnies because we've got older making Ruby
42:36
Quakers, we've got shipping spares because we have black walnut making the gray edge Boma Loka
42:41
we have field sparrows because we have folks making red line pan of pot as we get tested tip base because we got black cherries making daddy pinions. We've got CVS with a nest right over my lamp on my front porch because we got a lot of native grasses making skippers. We have robins. Yes, they eat words, but they eat the white lines thanks to and that is a well that lives in this area and other weeds. Our chickadees are eating tulip tree beauty that produced on those
43:07
those tulip trees, wide eyed is getting the spice pushed swallowtail because we got space bush and sassafras to close relatives believe it or not got house wrens because a hickory is making copper under wings bluebirds because we have sycamores making drab prominence. We've got 60 species of birds that have bred on our ten acres because we've got the food that supports them. And I guarantee they're not 60 species of birds breeding on my neighbor's yard who also has ten acres.
43:33
But 100% of the plants on his yard are non-native
43:38
I'm telling you all this because this is a headline we see frequently. Two thirds of Earth's wildlife has vanished since 1970. But not at my house because you put the plants back, you can turn this around by putting the plants back. So don't give up when you see scary headlines like this
43:56
point is by choosing the right plants using more of them. We could restore insects everywhere. This could be the backyard landscaping paradigm.
44:05
It's beautiful. We could do it. There's nine things I want to leave you with that you can, you can focus on to restoring ecosystem function in your yard by returning insects to your yard. And the first one is reducing the area of lawn. And we talked about this last night. We've got an area the size of New England and lawn a status symbol which is dedicated to to
44:31
well, it's an ecological dedicate, dedicated to nothing, is dedicated to telling everybody how neat we are. So I'm suggesting we cut that area lawn. You know, this is a church I drive by and Holly Springs, people go to worship God's creations on Sunday and the rest of the day they kill them all on the outside.
44:51
We're not thinking about about about our impact on local landscapes,
44:57
but we could reduce the area of lawn for sure. We want to plant for specialist bees. Let me talk a little bit about this. Sam Draghi is a guy at the Patuxent Wildlife Research Center. He's Mr. Native Bee these days, these days. And he says we need to plant for our specialist bees because the general bees can use those plants as well.
45:18
So we have about 4000 species of
45:21
native bees in this country. Over a third of them can only reproduce in the pollen of particular plants. How do you know what those plants are? This is a new website from the National Wildlife Federation.
45:33
It's part of their their website called Keystone Plants for Specialist Pollinators. And it's arranged by ecoregion, not by county anymore. So you figure out what ecoregion you're in and it will give you the list of the best plants that are supporting the most specialist bees, and then the general list use them as well. So, for example, goldenrod is often way up at the top there. My house, 12 species of bees that reproduce and goldenrod they wouldn't be there if I didn't have goldenrod.
45:57
But if you look at goldenrod, the honey bee and the bumble bee, they're all over it too. So we're not losing any generalists by using these plants.
46:04
Okay, remove invasive species from your property. We know about invasive species. I mean, these are common. One saw a lot of Callery pear flying in here where I come from. Porcelain berry is the kudzu of the north. I'm glad you don't have it, but you do have kudzu. The
46:20
Chinese elm. I heard somebody say today, not another bad plant. Invasive white boy up north. It's. It's terrible. It just replaces everything. Let's put some American Elm back. I've got American homes that are 20 years old now. They're 80 feet tall. They look great. Not sick. At all if they die. I've gotten 20 great years of productivity at a much more than we get out of Chinese. And you know, this list is much, much bigger than that.
46:43
Most people believe it or not, have invasive plants on their property that they haven't even thought about. You know, you're burning bush, you barberry, all of those things. So let's start by removing those use keystone plants. We've talked about that landscape for caterpillars. I mentioned this last night, but I'm going to go over it quickly. We have the landscape under our trees in a ways that allows caterpillars to complete their development. So I live in Chester County,
47:08
Pennsylvania, where Oak supports 511 species of caterpillars. A few of them, like the Polyphemus Moth, complete their development on the tree by the caterpillars eating the leaves. Then they spin a cocoon and hang from the tree. Then they emerge as an adult, and then they do it all over again. Everything happens on the tree, but most species don't do that. Most species. 480 of them finished growing as caterpillars on the tree, and then they drop from the tree.
47:33
And they will go their way beneath the soil. If it's loose enough to do that and put paint underground, or they spin a cocoon in the leaf litter that's under the tree. And that's the problem. There is no leaf litter under the tree. We don't tolerate it. We rake it all away. And it's a very uninhabitable place for this caterpillars. We mow and come back. The soil so that it's impossible for them to get underneath the ground. And and when we landscaped like this,
47:58
even if these are the correct trees, we've created ecological traps and it's another major cause of insect decline around the country. This is what most people do. They've got a tree in the yard. We're going to measure what happens to caterpillars this summer. I've got a new student coming in to do that. But I guarantee this caterpillars survivorship is going to be higher in a landscape like this where you've got a layered landscape, you've got your tree,
48:20
maybe a dogwood here and then native azalea and ferns and groundcover. It gives the caterpillars a soft landing. They can get down there, they can get underground easily because it's not compacted nobody's going to mow them. Nobody's going to step on them. Survivorship would be much higher. This is where you could do your your spring, ephemeral gardening. You put beds around your trees this is how you shrink the lawn. Everything comes together, put more plants in your in your landscape
48:46
and you'll help the caterpillars and you'll get rid of the line. It'll be great. Use your native ground covers liberally. Things like wild ginger and maple and foam, flower and ferns. All of those guys are protecting those caterpillars and reducing the area that's in line.
49:02
Reduce your light. Pollution studies all over the world are telling us that the lights we have on at night are another major cause of insect decline. This is all the ways that they're killing our insects, particularly those moors that create the caterpillars that run our our our food webs.
49:21
This is actually good news to me, folks, because we have to turn around insect decline. That's what we're talking about here. We've already lost 45% of our insects. If we can help by just flicking a switch, that's easy.
49:33
We're getting off easy by doing that. But a lot of people will say, Well, I can't turn off the the bulb over my bathroom. My garage or my front porch because the bad man will come.
49:43
All right, put a motion sensor on it. So it only turns on when the bad man does come
49:48
and the bad medicine come very often. I know that. Or take the white bulb out of your your security bulb and put in a yellow bell. But yellow led is the
50:01
it's the best because it uses the less energy than the reason yellow is better is that nocturnal insects are less attractive to yellow wavelengths. So simply by switching out the bulb, we can reduce an awful lot of insect mortality. Just take those white bulbs, make them yellow. We'll save millions of insects every night and we'll save millions of dollars if they're LEDs,
50:25
oppose mosquito spraying. I don't know how much mosquito spraying you do down here, but
50:30
mosquito spraying kills not just mosquitoes. It kills everything that it comes in contact with and it comes in contact with an awful lot of things. You can work really hard on your your landscape and transform it. But then if you have a mosquito farmer come, it would kill everything on it. We have a retired faculty member who's got a wonderful landscape. He's got every native plant in there, and he says, I have no monarchs at all. I said, does your does your neighbor fogged yes.
50:55
It doesn't stay on the properties that are that are fogging. It also doesn't control mosquitoes. Unfortunately, you've got to you don't control mosquitoes in the adult stage. You control them in the larval stage. In order to control mosquitoes in the adult stage, you have to kill 90% of the adult mosquito. Joe kills between ten and 50%, which is why he has to keep coming back and you have to keep paying him to not control your mosquitoes.
51:18
If you really want to control mosquitoes, do it in the larval stage. Get a bucket, fill a full of water, put in a handful of straw or hey, let it build up colonies of algae and
51:29
diatoms. That's what mosquito larvae eat. The female mosquitoes love that brew. They will lay their eggs in there. Then you go to the hardware store and you get a sheet of mosquito dunks, but one mosquito dunk in their course. $9
51:43
and that's bacillus thuringiensis. It kills aquatic it. And the only aquatic dip there in your bucket is a mosquito larvae. So if the dragonfly gets in there, doesn't hurt it at all. If your dog likes it, if a bird drinks it, no problem, put a screen over it so your chipmunk doesn't drown himself. But this is a cheap, effective and directed way to control mosquitoes, particularly if everybody does it.
52:08
As a matter of fact, minimize insecticide use overall. You know, you go to the hardware store and there are shelves lined with all the ways we can kill our insects. And except for term control, which which is serious stuff, we have to control them. Almost all of it is totally unnecessary. It just it supports our intimate phobia. You see something crawling, you got to kill it. No, you don't. You really don't. Especially the spiders that are eating the mosquitoes
52:34
that you just hired, mosquito Joe, to poison everything for
52:39
but here's here's. All right. Bug zappers. We did a study back in 1996 looking at the percentage of insects killed at bug zappers that were actually mosquitoes or biting flies of any any kind. It was 0.02% of the kill mountains of mosquitoes of dead insects there. But they're not mosquitoes. So people get thrilled when they hear a zap. But it's just another another cause. But here's a new product. I don't know if you know about this. It's called the mosquito racket. Same. I tried one of these
53:09
I haven't either, but I'm anxious to do it. You I guess you push a button so when you're laying in bed, the mosquitoes circling around, it drives you crazy. You can hit them with that. And it electrifies him, but only him. Not all the other miles and everything around there or sitting at your back, back porch, you could you know, you could take out your mosquitoes real fast with the So I'm anxious to try that.
53:30
Okay. You know, a lot of people say we can't do any of this as important as is. We can't do any of this because my size, I'm not allowed to. And it's true. Nature is home. And associations, civic associations can have very strict rules about how you landscape. You know, your grass can only be a quarter inch tall. And every every plant has to be a chameleon and all the other rules that they have. But who made those rules? We did. People made those rules back in the seventies
53:58
when they didn't want rusty cars in the front yard. They said, we're a high class neighborhood. We're going to make rules. Okay. And then they went crazy with landscaping rules so that everybody was identical we made the rules. We can change the rules, infiltrate your way,
54:14
educate them from within, become their friend. If you go in and say, you know, you're bad, I'm good, and you have to do it my way, it's not going to work, but educate them that those you know, we have ecological challenges these days and these rules aren't helping much. I am hearing from people who have done this saying, hey, it works my ways changing their rules.
54:40
So I'm encouraged, but it takes action on our part. Okay. We are wrapping up here. I'm going to return the way I started. E.O. Wilson wrote Health Earth in 2016. It was kind of a culmination of his lifetime study of biodiversity and how to save it on our planet. And his message, just like the little things around the world, his message was very clear. If we're going to save life anywhere on planet Earth, we have to save nature. We have to save functioning ecosystems.
55:10
The stuff that keeps species around on half of the Earth
55:16
and he spent most of the book talking about the science that supports that statement. And then he ended the book. He didn't tell us how we're going to support life on half of the Earth, how we're going to support nature and half of planet Earth. Remember, half a planet Earth is already in some form of agriculture, and we're in the other half. All 8 billion of us with all of our roads and airports and infrastructure and detritus. And we don't have a third half to put aside for for nature.
55:40
So how are we going to do this? That's basically what I talked about last night. It's the concept that we need a new approach to conservation. We need to now live together. We've got to give up the nature, the notion that humans in nature can't coexist
55:57
and we've got to find ways to live with nature everywhere, not just in parks and preserves.
56:03
And again, I'm going to emphasize this. I said it last night, but it doesn't mean you have to save insects or save nature for a living, but you can save them where you live. And if you do, it empowers you. So many people feel totally powerless these days because our our Earth's problems are so huge. And what can one person do or one person can do? All the things I just listed, you can shrink your lawn or use Keystone plants and turn out your lights, stop with your insecticides,
56:30
do all the things we do every day without thinking about it. And really turn it around. How do I know that? Because that's what we did at home kind of fell into it. But all we really did was put the plants back. We never did have our lights on, and we didn't use any any pesticides and it comes back in spades. So so it works. And it also shrinks the problem down to something. It's manageable for each one of us.
56:54
If you think about the entire Earth's problems, you do get depressed. Just worry about the peace of the earth that you can influence. That's where you live. If you own property, that's obvious. That's where you focus. If you don't own property, help somebody who does help a land conservancy, help a park, help a preserve, help a university, turn things around so insect decline is a global problem, but it's got a grass roots solution
57:19
and its aggressive root solution, I believe, really is going to work. We created this problem, but we can solve it.
57:26
Thanks very much
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