In this episode of Gardening Unplugged, recorded July 24th, 2022 during our Open Nursery and Garden Days, our Research Supervisor Bill Reynolds tries to identify as many sounds as he can while walking the garden. His knowledge of insect noises is so good he can tell when serious life drama is happening in the canopy.
I'd like to welcome all of you to Juniper Level Botanic Garden and we are going to take a little excursion, kind of walk through the gardens. Today we're going to be using our ears and try to use our eyes to see if we can locate and see what some of the sounds are in the garden.
One of the things that is really important with gardens to consider... we always want to try to accommodate some aspect of wildlife. There are certain sounds for summer, kind of signature for summer, among those are crickets, katydids, cicadas, even frogs. Of course, birds. And birds are dependent on - What do birds eat? They eat plant seeds, but they also eat... insects. So, we always want to make sure that there is a balance in our gardens.
How many of you, when you're working in your yard or in your garden, you hear things? You hear things in the trees, you hear sounds. Do you often know what those sounds are though and who and what's making them? Some of them you know? Not all of them? Well, we're going to, that's good about 50 percent, and we're going to talk about some of the groups of the animals and the insects that are making these sounds and we're going to talk about some of the specifics because, believe it or not, each different species has a different call and a different time of day, often times, that they're active. With that said, we're going to start this way. We're going to gravitate toward the 41 garden, which is the oldest and, in many respects, probably the more established garden.
Cicadas are active during the hottest part of the day
And as we walk, as we make our way, you'll hear in the distance some of the cicadas. And the one that you're, let's take a second and listen. You hear that kind of high-pitched oscillation? That is one of the earliest cicadas that we hear here in North Carolina. That is called Neocicada hieroglyphica. About mid-July, end of July, they become less common. So that is kind of, he's one of the last ones that you're going to be hearing this time of year because it’s more of a late May through June, into the first week, first half of July.
Only the males make these sounds. With cicadas, only the males make the sound. And do you know why they make the sounds? Does anyone know why a male cicada would make sounds? To attract the females... exactly. And what's really interesting, cicadas are making that sounds with their ear drums and a resonance chamber. You know the ear drum is a membrane that bounces. They have a resonance chamber. The abdomen of the male is basically hollow, like a drum. And their muscles, they can contract and move, they can generate air flow and pulses that make sound. So, the sounds are potentially, they're using mechanisms that are part of their hearing system to generate the sounds. That's kind of unique and interesting.
Another thing that's cool about cicadas is that, unlike other bugs, just like you, to thermo-regulate they sweat. So, they use evaporative cooling to cool down. And cicadas have very specific temperatures that their active. And most of them are, you're not going to hear them until their body temperatures are upper seventies, maybe low eighties or warmer. So, they have to warm up. They like it kind of hot. Which is why we call them dog day cicadas because these would be the dog days. The hottest time of year. So, we're going to walk over to the 41.
They die. Cicadas are seasonal. They take, most species, several seasons to go from egg to adult. And they only live for maybe a week or two, up to a month. The adults feed on sap. Just like the nymphs, they have a beak, a mouth part where they feed on sap. They rarely occur in numbers that do any kind of damage. And the cicada you're hearing are all native and they're typically on native plants. So, there's no, no real damage done by them. Essentially, they're beneficial because they move nutrients through the forest and they're also a huge part of the food chain as almost everything eats them. Everything from snakes to lizards to birds to squirrels to foxes, raccoons, skunks. There’re really very few things that won't eat them, including humans. Earlier humans used to eat them. And they taste kind of like cashew when they're cooked. Kind of the texture of shrimp with the flavor of cashew. Not that I'm a big bug eater but I have tried them. They're musical. I kind of think, what would summer be without them? They occur in almost all the temperate tropical and sub-tropical parts of the world. In the US we have about 200 species. With crickets and katydids, quite a few more. So, there are many species of crickets and katydids. But what you're hearing during this hottest part of the day, these are cicadas.
Most sounds in the garden happen from sunrise to lunch
Everybody gets quiet. Most of the sounds we're going to hear in the garden, we're going to hear them within 30-45 minutes of sunrise to just before lunch. Then during that hottest part of the day, things are a little less active. Then it begins to pick up again a little later on in the afternoon when the sun intensity is a little less and the temperatures begin to be a little bit more moderate. But a lot also has to do with the sun angle because right now, the sun's straight overhead, or nearly so, so that makes it a little bit hard for a lot of these animals. They do exactly what we do. They find the shade, they find something to drink, and they chill for a little while. So, a lot of the critters that would be making sounds are being quiet. Or being less active right now.
So, we'll walk this way. Isn't that always the case? Things are really active until you try to talk about them or try to find them. Let's stand here for a second. I hear one in the distance. Sounds kind of like a ratchet. It kind of has a cranking sound a zip, zip. You can barely hear it. They were very active a few minutes ago and the second we walk over here, everybody gets quiet. If you put your hand up to your ear, kind of listen that way, it just sounds like if you had a ratchet, a crank. That is... they were loud the other day. A lot of it is timing during the day. They were actually loud about an hour and a half ago.
That one that sounds like a crank, I always think it sounds like a ratchet, that one's called Robinson's Cicada and they will call from late morning all the way into the evening. So, we'll keep on walking.
They are. There's a bunch of closely related ones but each one has a different call and a slightly different time of day that they're most active. Sometimes after we get, after the irrigation system runs, or if you get a rain, you'll hear frogs. And grey tree frogs are one of the common ones that we hear in the garden. We also sometimes hear the green frogs. Green frogs sound like a banjo, kind of a thonk. So sometimes you'll hear the green frogs. We have leopard frogs; we have a number of species of frogs. But usually frog activity is something you're going to hear right before, during, and right after a rain. So, frogs are going to be active when we've had water. And like I said, when we run the irrigation systems, sometimes the frogs get really excited, so you'll hear a lot of frogs. Yeah, they do. The frogs get really excited with the irrigation system.
Water features can add a soothing sound to the garden
Now you can hear them, I think, a little better. Sounds like a ratchet, like a tool. Sounds like a gear or a ratchet. That is a really common cicada around here, Robinson's cicada. I was hoping we would hear a few more different kinds. But you can definitely hear them over there. No, not all the sounds in the garden are animals. Here's a good sounds in the garden. This is the sounds of running water. And so, with water features, like creeks or you know, some people have bird baths that will trickle down and then recycle back up. Sometimes water is a really nice sound in the garden. It's very soothing, it's very calming. So, it adds a lot of dimension to a garden to have a water feature. Not only is it good for certain kinds of plants, but like I said, it also adds a sound element that can be very soothing. It is very cool. I do to. You're not the only one. I kind of want to take my shoes off and walk through it, cool my feet off.
Feels good, doesn't it? It was a little warmer than you thought. Okay, you hear that one? Almost sounds like a, like an air conditioner fan. It's constant. It's got a little bit... that one, lyricen (Neotibicen lyricen). That's another species of cicada. All of these cicadas that you're hearing are... No, it's a lot of different species. Each one is making a different sound. Do you see how that sound is very different than that other sound?
A little bit later in the evening there's one, it's actually the largest cicada in North America. They're common in people's yards that have oak trees. They like oaks. How big are they? They're big. They've got about a 4-inch wingspan. But it's also one of the loudest, very, very loud. And you will only hear those, not only, but they are most active that last 30 to 45 minutes before sunset. But they're really loud. So, this evening when you go home, listen to that last 30, 45 minutes and you'll start hearing them. And you'll recognize them immediately because it's going to be a very loud, almost a roar through the trees. But that's a really cool one. And a lot of people from different areas, when they move here, and even some of my neighbors, they'll say - What is it up in the trees making that sound when it starts getting dark?
Crickets and katydids are active at night
But, like I said, each species will call at different times. And the same thing, like at night. When the sun has set, you sit on your deck, you'll hear different buzzes or sometimes constant buzzing, those are your crickets and your katydids which are active at night. Most of those are going to be more nocturnal. Whereas your cicadas and some of the katydids are going to be diurnal, which means during the daytime. So, either right as the sun is rising or right as the sun is setting. But once it is really dark, you're not as likely to hear those insects, you're going to start hearing the crickets and the katydids. How do you separate the sounds? Well, you know, they do sound similar. Part of it is just kind of familiarity and another part is getting out in the field and when you're hearing these sounds, isolating them, find what's making the sound, and catch it. So, like with cicadas, believe it or not, there are nets that are 30 feet long. And you have to find it on the branch calling, and you have to catch it, get it in the net and get it back down to the ground without it getting out of the net. Which, that isn't always easy.
But you have to isolate a lot of those sounds so a lot of it really is about collecting them when they're out making those sounds. And the same with frogs. I don't know if you've ever noticed, when you hear something, like a frog or an insect, if you have ever tried to find it. It seems like the closer you get then the sound seems to be somewhere else but then you look and the sounds, have you ever noticed that? If you really want to try and triangulate where an animal is, think about you're...how many of you have dogs or cats? What do they do when they're looking at something with their ears? The ears immediately start to... if you take your hands, put your hands behind your ears, aim your ears, even if you aim your ears toward these people talking, that's another sound in the garden, you can begin to isolate and triangulate where a sound is. And if you ever watch a cat's or any other animal's ears, the ears are in constant [motion] because what they’re doing is they’re collecting the sounds waves and their focusing in. Our ears work because they've adapted to human language which is a little more of a broad spectrum. But if you're trying to isolate one little sounds in the garden, you can do what a cat or a dog does. Just take your hands, scoop them behind your ears, and start kind of ... and believe it or not, you'll be able to figure out, kind of isolate where the sound is coming from. So, it's a little trick you can do. You can teach kids to do it. Kids love it. Once they figure that out, finding the cricket or the frog is really easy then.
You have any questions so far about anything? What are those sounds coming from over there? That's water. Let's go over here. You know we were talking about water features.
And as you get closer to the water features, hearing the other things will be a little more difficult. Sometimes you can hear things like dragon flies when they go zipping by. Even the hummingbirds when hummingbirds come to the feeder. Have you ever heard the hummingbirds, there's kind of a whirring to their wings. And of course, we all are familiar with the sounds, the high pitch whine of gnats and mosquitoes, right? We all know that sound. That's another sound of the garden. It's the sound of outside.
Sometimes working in the garden, during open house, we hear sounds that come from the public. There's always that potential when someone has tried to touch a plant that doesn’t particularly like being touched. Those can be interesting sounds. But that’s more of a botanic garden sound rather than a home yard sounds. Or the sound of a mother telling a kid to get out of the water. The way this grotto is designed, to face towards the house, if you sit here with this running water one of the things it really does for a garden. Right on the other side of it, there's a pretty busy road. But if you sit here, anytime of day, and you're listening to just the water running, you will almost never hear a vehicle on Sauls road. So, there are ways also which you can use sound in the garden to shield against other sounds that you don't want to hear. And water is an excellent way to do it.
Do you have any questions? No?
And I'm not hearing many birds, but like I said, when we're in the middle of summer, and it’s the hottest time of day, most of the animals are doing what most of us would do. Kind of avoiding the direct heat. So. they're out and about, they're just not going t be noisy until I quit talking about them and they get back over to the visitor's tent. Then, about 4 o'clock everybody’s going to start making a lot of noise again.
Plants can also make sounds
Plants can also make sounds as the wind rustles through. Depending on, let's step aside here. The automobile passing is also going to make a sound unless it’s a Tesla, they don’t make much sound. Right? I like the sounds a lot of times when we get breezes and the other sounds that you get with plants. Some plants are better at making sounds than others. I like the sound, in my yard, even here in parts of the garden, when the wind is blowing through plants with really big leaves. Like the bananas, or the palms. You get that rustling sound which really to me sounds nice. So, like I said, all kinds of sound elements in the garden. They don’t necessarily have to be made by animals. We'll come around through here, get back in the shade a little bit more.
Now we can really hear them. And those that are zipping back and forth, to me, I always thought it sounds like a ratchet or like she said, a clock, when you're winding a clock. Again, that's Robinson's cicada and they tend to be high up in the tree. Some species are lower, but that one seems to be pretty high. The insect itself, they'll call from a lot of different trees but they like tress that are in the cedar family or the juniper family. They like things in the Cupressaceae family. They don't damage the tree but the adults and the nymphs feed on sap at the roots. But one of the things that they do when they're feeding on the sap, you know we think of insects and things that are feeding on plants as being a bad thing. They're also aerating the soil. They're also, when they're feeding on the roots, it encourages the plant to send out roots even more and further which allows the plant to interact more with the soil. They're activity in the soil increases the presence of a lot of the symbiotes in the soil that the plant needs. So, there's a very strong beneficial relationship between many of the insects and the trees and the plants that they feed on. The plant needs the bug, the bug needs the plant. And if you think about, you’re looking at many, many thousands of years of interactions so it's a really good mutual [relationship].
They don't really go deep into the plant. But they feed on the sugar filled water that the plant is moving. And again, it really has no impact on the plant. They're related to some bugs that are really bad like aphids, but cicadas don’t really occur in those numbers. But even the ones that do, the periodicals, they're natural pruning for the trees. Every 13 to 17 years, that's a great thing for the entire forest. There are some species that come every 13 to 17 years and they come in by the millions. Some cicadas. They’re called periodicals and there is this impression by a lot of people, oh this is terrible. But it’s the single largest dose of fertilizer that the forest will get in a single event. So, it’s really good for the forest. It’s good for all the animals, all the animals have full bellies. There’s a bird. You know, what kind of bird is that? Some birds I know, some of them I don’t. I definitely recognize.
And you know something, I’m really good with the calls of a lot of the bugs, a little less so with the calls of the birds. You know, what’s one of the best ways to find out what the sound is? Let’s go see if we can find it. I do recognize our cat birds, I do recognize our fishing crows, I do recognize the owls and the hawks when I hear them. I recognize some of the more common birds. The blue jays. You see him? But birds are an excellent, they're a great element. It keeps moving over there, did you see it? I did see it but now it’s behind the ...I do see it but I’m not getting a really good at it.
But when you have a garden anything you can do to encourage seed sets, you know a lot of times we want to cut back our flowers. I like to leave my black-eyed Susans, my coneflowers, my sunflowers, even after they flower because my gold finches like them. So, you know, we want to encourage things like birds. But birds are also another good soothing element to have in the garden because of sounds. And I'm beginning to hear more birds. I am woefully deficient when it comes to identifying birds based on their calls. And you would think that I would be better at that but there's so many ornithologist that specialize in birds, I kind of specialize in other sounds that nobody else really thought about. Wish I could answer your question on some of these little birds. There are some with the fluttering of the wings. There are a few species of butterflies that can make clicking sounds with the wings. Which they will do in territorial displays. Some of the brushwood butterflies can kind of click their wings as kind of a thumping of the wings together. The wings themselves are kind of a hard membrane exoskeleton like the rest of the insect and so there are a few species that can make a clicking sound with their wings.
Did you hear that sound? That's the sound of a cicada making an alarm call. And I’m thinking as long as that alarm call was somebody got it. And there’s a big wasp called a cicada killer that will get them. And there's birds that will get them. So that was a long enough squawk I think somebody found that one. So, its dinner now for somebody. You know, it’s part of the food chain. Well walk around this way. You notice how everybody got quiet? Usually, when a cicada makes an alarm call like that, they are all going to get quiet. Because that means that somebody is out there looking for them. And even if it is a different species; they all recognize that call. That call is the scream of yikes. You feel bad? You know, I just look at it as being a kind of necessary evil. It’s probably already done a lot of what he needed to do; he’s probably already mated. And you know, somebody's got to eat.
Do we have any other questions?
The greater the biodiversity in your garden, the fewer pest problems
So, some of the sounds with gardens, birds, crickets, grasshoppers, katydids, cicadas. Sometimes the more integrated that our gardens are, with plants and animals, the greater the biodiversity, the more we can discourage pest problems. Because nature, you know, exists in a really good balance. And unfortunately, with our yards, one of the things we do is we throw that out of balance. And so, when that balance, that equilibrium is off, it tends to open up a niche for animals and even plants that we would consider problems. So, I try to encourage people to maximize your diversity of what you plant. Don't plant all the same thing in one place. Spread it out. There are ways that critters can be discouraged from being in the garden and doing things that we don’t like them to do. I’ve got a dog and she’s a great deterrent. I let her out in the yard, and she does the perimeter, sniffs it, marks it. The deer don’t particularly want to go anywhere the dog has marked because technically a dog is a wolf. And to a deer it really doesn’t think any differently. It smells that and it’s like, Okay. Same for rabbits? That’s a little different. I don’t really know how to answer all those questions, ethically anyway. I just say, it’s something that we really have to learn to live with. You know, we are ourselves part of nature and it’s an inevitability and there’s always going to be something that gets in our yard and does something that we're not going to like. We just have to try to strike that balance and find out what we can and can’t live with. Do we have any other questions?