MR. KOJO NNAMDIFrom WAMU 88.5, at American University in Washington, welcome to "The Kojo Nnamdi Show," connecting your neighborhood with the world. If you don't get the big picture, you can't see the forest for the trees. Well, what is going on in our local forests and with those trees we're so keen on anyway? If you think the tree cover is thinning in your local park, you're probably right.

MR. KOJO NNAMDIAnd if you've noticed more deer than ever, it's because there are more, as many as 300 deer per square mile in D.C. proper, not suburban Maryland or Virginia -- D.C. That's more than 10 times the number considered normal. So how do we strike a normal balance of flora and fauna in our local ecosystems? Joining us to have this conversation is Bill McShea.

MR. KOJO NNAMDIHe is a research ecologist with the Smithsonian Conservation Biology Institute, part of the National Zoo. Bill McShea, thank you for joining us.

MR. BILL MCSHEAThank you, Kojo.

NNAMDINevin Dawson is an associate agent of agriculture and natural resources and forestry stewardship with the University of Maryland Extension's Wye Research and Education Center. Nevin Dawson, thank you for joining us.

MR. NEVIN DAWSONThank you. My pleasure.

NNAMDIAlso with us is Kevin Sullivan. He is a wildlife biologist and the state director of wildlife services in Maryland, Delaware and D.C. for the U.S. Department of Agriculture. Kevin, thank you for joining us.

MR. KEVIN SULLIVANThank you for the invite.

NNAMDIYou, too, can join the conversation at 800-433-8850. You can send us a tweet, @kojoshow, email to kojo@wamu.org. Or simply go to our website, kojoshow.org. Join the conversations there. If you have questions about the flora and fauna in your backyard, just give us a call, 800-433-8850. Nevin, I have driven or run through Rock Creek Park most every day for decades, and I've noticed that the trees there have thinned.

NNAMDIIt's my understanding that this isn't an issue that is unique to this park. What's going on?

DAWSONWell, you mentioned the increase in the deer population. And they eat in a way we call browsing, which means that they kind of nimble here and there, different parts of different plants, much like you'd shop in a grocery store. In our current state of affairs when deer populations are so high, they tend to eat more vegetation than the natural environment can sustain in a way.

DAWSONSo that understory that used to be there -- and that's the natural home of a lot of bird species and other critters -- is actually thinning out because of the high amount of food it takes to feed these huge deer herds.

NNAMDIBill McShea, having no deer is not natural either. But you've set up some deer-free exclosures. What do these plots of land look like? And how are they different from the acreage around them?

MCSHEAWell, we started this over 20 years ago. And what we wanted to do was see, how would the forest change if we started changing the species' composition in those forests? And the first species we wanted to look at was deer. So we built these 10-acre exclosures, and we put them in the Shenandoah Park and at the Smithsonian's Conservation Biology Institute in Front Royal. And we put some at the George Washington Forest.

MCSHEAAnd we fenced out the deer back in 1990. And since then, we've been looking at how that world is different. And it's very different. It would be great to be able to show your viewers what it looks like. And we did put some pictures on your website. But it's more dynamic. It's more -- transitions a lot more. There are more places with shrubs, more birds, different mammals, different salamanders. The whole world looks a little different with less deer.

NNAMDIAnd, of course, as he mentioned, you can see those pictures at our website, kojoshow.org. People are probably dying to know how you keep the deer out of these spaces. How do you do it? And are deer the only wildlife that are kept out?

MCSHEAYeah, these fences are very clever. They're -- it's an American farm fencing that we flipped upside-down, so the bigger openings are at the bottom of the fence. So all the raccoons and possums and small things can come and go through those openings. But the deer can't jump over the fence. The fence is about eight feet tall. And that's not deer-proof, but it's deer-proof enough for us. If something gets in there, we can always chase it back out again.

NNAMDIKevin, controlling the deer population is a big challenge a lot of local communities are grappling with. Beyond the damage they're causing to the forest, why is it important to control the population?

SULLIVANIt's about striking a balance. The scientists have come up with figures, general numbers of deer, as you mentioned, you know, maybe 30 per square mile. And that's what makes it best for the ecosystem, the other species that live there, but then there's other threats. There's human health and safety threats. There's threats for deer-vehicle collisions. So it's really about striking a balance and trying to get that population to a suitable level.

NNAMDIIt's my understanding that Maryland has a new option when it comes to deer population control.

SULLIVANThey do. USDA Wildlife Services has developed an amino contraceptive or a contraceptive for deer. It's an injectable contraceptive. So you have to actually capture the animal, the female doe -- deer and give it an injection. And that injection can be a multiyear injection, and that's a nonlethal way to try to control the deer population.

NNAMDIWe're talking about our local forest ecology and inviting your calls at 800-433-8850. Are you suddenly seeing creatures that you've never noticed before? Tell us what you're seeing and where you're seeing it, 800-433-8850. Or go to our website, kojoshow.org, and join the population there. Bill McShea, deer aren't the only threat to our local forest ecosystems. What else is upsetting the balance?

MCSHEAInvasive plants and animals would be a place to start. We've brought in a lot of animals and plants as part of our moving products around the world that something can go from China to Bethesda in 48 hours. And when things can move that fast, then the animals and the seeds can come along with them. And as a result, we've got a lot of plants out there that didn't use to be there before.

MCSHEAWe have a lot of insect pests that didn't use to be there before. And those issues are in addition -- are on top of the deer situation. So, sometimes, solving a deer situation doesn't make that forest work well. It still has other problems that have to be dealt with.

NNAMDIIn some suburban urban communities, feral cats are also a problem, are they not?

MCSHEAA big problem. And that's a problem that is very difficult to deal with because everyone loves their cats. And these cats, when they're not sitting on your lap or out there eating birds and small mammals and -- dealing with that and making people more aware of the damage that these cats are causing is a major effort for a lot of state and federal agencies.

NNAMDIAnd, Kevin, I know people have been calling your office when they're seeing some kind of damage or some kind of negative interaction between themselves and wildlife. Have you been noticing a significant increase in those calls?

SULLIVANThe calls stay pretty steady. We have about 9- to 10,000 calls a year. We have a 1-800. It's a toll-free line. We partner with the Maryland Department of Natural Resources. And anybody from the D.C. metro area and Maryland can call that and get technical assistance. But we're not seeing a big upswing in calls. It stays pretty steady.

NNAMDIOkay. Gentlemen, please, don your headphones. We're about to go to the telephone. 800-433-8850 is the number to call. If you have questions about the flora and fauna in your backyard, give us a call, 800-433-8850. Here is Brian in Fredericksburg, Va. Brian, you're on the air. Go ahead, please.

BRIANYes, sir. Fredericksburg, Va. has taken on an urban archery season. It allows hunters, licensed hunters to take animals within inside the city limits with bows and arrows and crossbows. I'm curious if any other jurisdictions are considering this or similar manners to bring the numbers of deer down.

NNAMDIKevin Sullivan?

SULLIVANYeah, the state jurisdictions, Virginia and Maryland, both manage their deer populations many times with managed hunting. And Maryland has an effort to do that as well, to open up different urban areas and different opportunities where it's safe to allow hunters to go in and try to help manage the deer population.

NNAMDIOkay. Brian, thank you very much for your call. Kevin, we know deer populations are high. What other animals are we seeing more of? And how are they affecting the environment?

SULLIVANWe're seeing a real increase in vulture populations, a lot of the raptors. A lot of the birds are doing very well, eagles, ospreys. The birds are really doing well and rebounded quite a bit. As far as damage to the forest ecosystem, I don't think it's terribly high. But we do get calls with people with concerns about vultures. They're different animals. And we try to provide them technical assistance.

NNAMDIBeavers, et cetera. Are the bird populations at historic highs because, it's my understanding, of the elimination of harmful pesticides?

SULLIVANYeah, with the elimination of some of the harmful pesticides, DDT, you see a real rebound in the birds of prey or the raptors, the cormorant populations. We're really seeing a nice recovery of bird populations.

NNAMDIWhat's the problem with Canada geese?

SULLIVANThe Canada geese, there's -- they're a migratory bird. And they don't distinguish between the ones that migrate and the ones that don't, but there's resident Canada geese. So in Maryland, there may be 100,000 -- 80- to 100,000 resident Canada geese that don't migrate anymore, so what used to be there just in the fall and the winter is now there March through September.

SULLIVANAnd just their grazing and their defecation and some of those things are damaging and concerning to people.

NNAMDINevin Dawson, animals and people are not the only threats to forests. Plants can cause big problems, too. Talk a little about that.

DAWSONSure. Yeah, that's exactly right. Invasive plant species can actually crowd out native plant species. Japanese stiltgrass is an example of that. Just like it sounds, it's from Asia, and it can create what's actually a very beautiful green lush carpet on the forest floor. And it's -- it has a very attractive look to it. Folks who don't know any better might really enjoy walking through a forest that looks like that.

DAWSONBut the fact is that, because there's such a thick carpet of this invasive plant species on the ground, the native plant species are unable to capture the light resources they need to grow and thrive. And, again, that means that, in addition to the deer browsing the native species that would create that forest understory, this plant species is now also limiting the native species that can create that forest understory.

NNAMDIAnd I understand we need to make a distinction between invasive species and exotic species. What's the distinction?

DAWSONYeah, they're used together and interchangeably a lot of times, probably more often than they should be. Exotic species, technically, are anything that are not native, so anything that's been brought from another part of the country, or another country altogether, that did not naturally evolve in our ecosystem.

DAWSONIt happens that a fairly small set of those exotic species become problems because they're so good at growing quickly, and they're so good at reproducing that they -- something like Japanese stiltgrass ends up crowding out a native species. The invasive term refers more to those specific characteristics. And there are even native species that can, in some situations, be considered invasive as well.

DAWSONAnd the invasive term is more of a human subjective definition of a certain plant species, just depending on whether it's infringing on humans' preferred use of the land and preferred state of the land.

NNAMDIAnd Japanese stiltgrass, it's my understanding, is not simply invasive, but it takes a lot of resources from native species and chokes them out, resources like light, for instance.

DAWSONThat's right. Of course, plants need light to grow. That's how they get their energy. And that's usually the limiting factor in plant growth. And if native species, like an oak, for example -- if that acorn lands on the forest floor, has the moisture it needs to sprout, that little oak sprout can't get the light it needs to kind of go past the leaves of the Japanese stiltgrass.

NNAMDIGot to take a short break. When we come back, we will continue this conversation on local forest ecology and take your calls, 800-433-8850. Have you struggled to keep an invasive plant or tree out of your neck of the woods? How's that working out for you? Call us at 800-433-8850. I'm Kojo Nnamdi.

NNAMDIWelcome back to our conversation on local fauna and flora. We're talking with Nevin Dawson. He is an associate agent of agriculture, natural resources and forestry stewardship with the University of Maryland Extension's Wye Research and Education Center. Kevin Sullivan is a wildlife biologist and the state director of Wildlife Services in Maryland, Delaware and D.C. for the U.S. Department of Agriculture.

NNAMDIAnd Bill McShea is a research ecologist with the Smithsonian Conservation Biology Institute, which is part of the National Zoo. We go directly to the telephones where Mike in Mount Airy, Md., awaits us. Mike, you're on the air. Go ahead, please.

MIKEGood afternoon, gentlemen. I have a concern about the amount of hormones that was in the deer because I know hunting is a big issue in Frederick County, where I live. And it's one of the only types of meat that you can get that don't have any hormones in them at all from the contraception -- contraceptives, sorry.

NNAMDIWhat do you say to that, Nevin or Kevin?

SULLIVANThe contraceptive use will be strictly managed by the state agencies. The deer will be marked. And any hormonal effects -- there'll be no effects to the meat or anybody consuming the meat. It's healthy, and they're actually naturally already existing hormones that are in the product.

NNAMDIMike -- go ahead. Go ahead, Mike.

MIKEThat answers my question. Thank you very much.

NNAMDIOkay. Good. Thank you very much for your call. We go on then to John in Washington, D.C. John, you're on the air. Go ahead, please.

JOHNHi, Kojo. I love your work. They -- back to the topic of invasive species, I thought, when you brought up the Japanese stiltgrass, you touched on kudzu, which -- perhaps it's my imagination, but it seems to be proliferated more and more in the area. And it doesn't look particularly bad in the summertime when it's green, but it looks pretty awful in the wintertime.

JOHNAnd, I guess, the question is, is there anything we can do about that? I mean, it seems like places like Atlanta and others are completely overrun now with kudzu. Are we destined for the same future here in D.C.? Thanks very much.

NNAMDINevin.

DAWSONYeah, we're lucky enough so far to not be overwhelmed with kudzu like they are in southern states. It can create vast wastelands. They look like something from another planet almost, where kudzu has overgrown trees, cars, sometimes even people standing in the way.

DAWSONBut, personally, I have been hearing maybe a few more instances of kudzu in Maryland. And there are methods of control, luckily. But, unfortunately, they -- it takes a lot of effort. It's a very tough and fast-growing plant. They can develop tap roots with, you know, up to 100 pounds in weight. And those tap roots supply energy to the sprouts. So even if you kill the sprouts manually, over and over, they still keep coming back.

DAWSONIn terms of, will it be a bigger problem in the future? I certainly hope not in Maryland. I haven't seen any scientific projections of its growth, so I don't have a firm answer.

NNAMDIJohn, thank you very much for your call.

JOHNThanks.

NNAMDIHere now is Jude in Silver Spring, Md. Jude, your turn.

JUDEYes. Good afternoon. How does the -- I live at Leisure World in Silver Spring, which is a gated, fenced community, a very large one. We have a resident herd of deer, that are, you know, very destructive and also dangerous. In my case, a doe, a large one, charged towards me in June and would not give way.

JUDESeveral weeks ago, a pair of fawns came running at me while I was on the sidewalk, stopped short, then turned and ran to their mother. I want to know how a community can go about, you know, killing them off. What permission do we have to get and how do we do it, if the powers that be agree to such a thing? You have many people that say, oh, no, we're on their property. You know, they were here first. I don't agree with that at all.

NNAMDIKevin Sullivan, are Jude's experiences unusual?

SULLIVANThey're not unusual at all. The first thing I would say is just treat all wildlife as it's wild. It is wild. So, although it looks cute and cuddly, just keep a safe distance from it. But to answer your specific question, what to do, your first step would be to call the state agency. And, in your case, it would be the Maryland Department of Natural Resources. They have two excellent deer biologists that will help your community.

SULLIVANThey do community-based deer management and programs, but I would suggest your first call be to the Maryland Department of Natural Resources.

JUDEAll right, thank you. They have become so tame. They do not move. I can be within a yard of them, and they will not move. And I think, to me, that's very dangerous and very objectionable, so thank you very much.

NNAMDIJude, thank you very much for your call. On the other hand, Bill McShea, many city dwellers and suburbanites idealize nature. But when confronted with the reality of spending time in the woods, all those bugs and thorns -- we could get lost out there -- and they shy away. How do we get past that? And why is it important to get past that?

MCSHEAIt is important, Kojo. I think that we need our woods. They serve -- all our forests serve a very important function in the state for cleaning the air, cleaning the water, providing stability to our ecosystems. And if we don't use those woods, we're going to value them less. It'll be hard to put the tax dollars and the government staff behind managing those woods, so people should use them more.

MCSHEAAnd, I think, there is a lot fear out there right now for disease transmission or angry deer or things like that. And I think it's generally unwarranted that a lot of what is now older generations spent a lot of time in the woods and got their love of nature from just hanging out and seeing what went by. And that really doesn't happen too much anymore.

MCSHEAAnd I think there is not -- we hear a lot about, oh, something happened in Kansas, or something terrible happened in California. And, in reality, the woods are a relatively safe place, and we should be enjoying them and appreciating them a lot more.

DAWSONYeah, and the reason that -- I, personally, ended up...

NNAMDIThis is Nevin Dawson.

DAWSON...in the career that I am now, is that, as a child, I spent time in the woods, and I grew to appreciate them, eventually, love being in the woods. And, you know, some of that was my parents saying, stop playing the video games, go outside and play. And that was pretty effective. I only had an acre lot that I grew up on, but there was enough woods there that, you know, I got very comfortable in them -- bugs don't bother me -- and just grew from that.

DAWSONAnd I think it's very important to start the appreciation in the childhood stage. That's -- you know, that's where people, a lot of times, develop their likes and dislikes. And kids can spend time in nature. There's all kinds of studies on the benefits that come from that, and there are campaigns like No Child Left Inside that I think are very valuable. And it's just a very important part of growing up to me.

NNAMDIIf you'd like to join the conversation, call us at 800-433-8850. How do you cope when wildlife creeps into your life? 800-433-8850, or go to our website, kojoshow.org. Join the conversation there. Send us a tweet, @kojoshow, or email to kojo@wamu.org. Here is Trish in Washington, D.C. Trish, you are on the air. Go ahead, please.

TRISHOh, good morning. I love your show. Thank you for having me. My question is -- I'm a native of Washington, D.C. I used to come downtown a lot and enjoy all nature, Hains Point. I'd go up the Potomac. I lived down -- at Georgetown now. And my question is, where are the birds? I walk the path -- the present trail. I walk up the Potomac, go over Memorial Bridge, come down the other way and across up on Sea Bridge. There aren't any birds.

TRISHWhat is our environment like now that we no longer have the native birds that were there when I was growing up? It's very (word?) to me.

NNAMDII don't know. Nevin Dawson, do you know? There seemed to be thousands in a tree in front of my house just a couple of days ago.

DAWSONYeah, I don't know the numbers or haven't seen any scientific studies. But there are a suite of birds that do very well in urban environments, and I think those are probably doing pretty well. But there is another suite of birds that require forest habitat for nesting, and these are things like -- Baltimore Orioles, for example, need a tropical -- migrants that come through and spend time in Maryland on their way, north and south.

DAWSONAnd the suite of birds requires not just a forest setting but interior forest setting, which means that there has to be a good chunk of forest that's more than 300 feet from the edge, so from the nearest lawn or the nearest sidewalk, for example. And that kind of habitat is very limited in Maryland and in the D.C. area, and that, perhaps, could be contributing to what you've noticed.

NNAMDIAnd here's Bill McShea.

MCSHEAYeah, I just wanted to point out that birds have a very complex lifecycle, especially the migratory birds that they're summering -- we think of them as our birds. But they summer here in Virginia, and then they are migrating down to Central, South America. And they're spending just as much time down there. And all the pieces of that life cycle have to work. If they lose an acre of land in Mexico, that affects birds up here in Virginia.

MCSHEAIf a migratory stop in Mississippi disappears, that affects birds here in Virginia. So it's something we take for granted. But there's a lot of moving parts. And if one of those moving parts starts to fail, then the result is you don't see the birds that you used to see. And that woods may -- in Virginia, may look the same to you. But the parts along the way have changed, and that results in less wildlife for you.

NNAMDITrish, thank you so much for your call. We move on to John in Arlington, Va. John, you're on the air. Go ahead, please.

JOHNYes, thank you very much. Our problem is a couple of cats, I guess, feral cats that have taken up residence at our house. And my kind-hearted wife has been feeding them for quite some time. And I -- apparently, they must be former house pets because they don't seem to be reproducing. And I called the Arlington Animal Control people.

JOHNAnd they said they'd be happy to give me traps and go and spay and neuter these cats and then return them to us to be released again. But that wasn't exactly the issue. The issue is that these lovable little creatures seem to be doing away with the local bird and rodent population. And I don't want to be a bad guy. But what do I do about these cats?

NNAMDIAny suggestions, Kevin Sullivan?

SULLIVANIt's a real concern nationwide, not just in this area. One of the conventional ways of dealing with that is just as you suggested, by trapping them, spay and neutering, and releasing them. But the wildlife community, the scientists and the biologists, really recommend against that. The best mode for that would be to capture them, give them to the animal control, or bring them inside with you, get them socialized, get them adopted out.

SULLIVANBut cats in the wild that aren't being taken care of, even if they're being taken care of with food supplements, they're always going to be a threat to our native birds and mammals.

NNAMDIJohn, thank you very much for your call, and good luck to you. I'll start with you, Bill McShea, but this question is really for all of you. When most of us picture a forest, we envision a vast expanse land with trees stretching as far as the eye can see. But it's my understanding that another issue's that most of our forest are simply not large enough to support complete ecosystems within their boundaries?

MCSHEAYeah, I think there's a feeling out there that if we let nature take its course, it'll manage itself. And, in reality, most of our forests are too small for that. We don't have complete ecosystems. And we've already jettisoned a lot of species that used to be there, and we've brought in a lot that didn't. So the idea that a forest can take care of itself is not proving out to be true, that if we want to have a healthy forest, we have to manage that forest.

MCSHEAWe have to bring some species down or bring some other species up. And the problem is we don't always know exactly what to do. We don't always know exactly how to deal with invasive species or how to manage the deer numbers. But doing something is better than doing nothing because doing nothing is not really working at this point in time.

NNAMDINevin Dawson, your take, same question.

DAWSONYeah, some of this question comes down to the definition of the word natural. You know, a lot of times, people will equate that word natural with the hands-off approach, the do-nothing approach. And that may seem like a good thing to do, but, really, by keeping your hands off a piece of land, you're letting other people in surrounding areas do some of that management for you.

DAWSONEven if it's someone in Baltimore opening up a shipping crate at the port and releasing a new pest, that pest may eventually make its way to your land. And if you don't do anything, if you don't take any action, that pest is going to change that forest land away from the state that you might like or consider to be natural. And there's similar issues with fire control.

DAWSONFire used to be a bigger part of our landscape and because we -- you know, fire is a threat to our infrastructure and our way of life, we manage that and minimize fire as much as possible. But that means that forest land is not getting that cycle of wildfire that it once had, you know, prehistorically.

NNAMDIKevin Sullivan.

SULLIVANYeah, as people look around in the D.C. Metro area, nothing looks the way it used to look. So we've already had quite an impact on the natural environment. And, as Bill and Nevin said, it's up to man to help manage, in an integrated approach, but we have to manage this forest now.

NNAMDIOn to the telephone again with Molly in Baltimore, Md. Hi, Molly.

MOLLYHi. I wanted to make one quick comment about the deer population 'cause that's been a big topic. But then I had a question about Tree-of-Heaven. The -- I've heard of a policy, and I don't know if it's instituted anywhere in the Baltimore, D.C. Metro areas, where they do targeted killing or hunting of deer and then donate the meat from the animals to homeless shelters. And I didn't know if that was something that we had around here.

NNAMDIKevin Sullivan, are you aware of that?

SULLIVANYeah, there are programs like that. They're, again, managed by the Maryland Department of Natural Resources. They are called Managed Hunts, and they can be with either bow and arrow or firearm hunts. And then even sportsmen that hunt on their time, recreationally, there's mechanisms that they can donate the meat to food and charitable organizations.

NNAMDIAnd, Molly, you had another part of your question.

MOLLYYeah, I noticed along the highways and actually in my own yard a tree -- I think it's called Tree-of-Heaven -- but I understand it to be invasive. And I was told not to cut it down or try to pull it out because that just encourages it to reproduce from its root system. And I wanted to find out if that was the case. And, you know, what's the best way would be to manage that particular plant?

NNAMDINevin.

DAWSONYeah, Tree-of-Heaven, also called Ailanthus, is definitely an invasive species. It is very quick growing and reproduces very well. And just like you said, if you just cut it down, that root system is still healthy and strong and will send many new sprouts up to take its place. For that reason, chemical control is usually the best way to control a Tree-of-Heaven. And there's a bunch of different ways to do that, like hack and squirt and a few other things.

DAWSONSo, yeah, and just notes on how you know it's a tree of heaven. The easiest way is, if you crush its leaves, it has a horrible kind of burnt peanut butter smell. That's one of the best ways to identify it, and it has a large compound leaf with many small leaflets.

NNAMDIWhy, therefore, is it called Tree-of-Heaven?

DAWSONThat's a good question. I'm not sure exactly where that name came from. Again, I believe the species was -- made its way here from Asia, so that may have something to do with its...

NNAMDIMolly, thank you so much for your call.

MOLLYThank you for your help.

NNAMDIWe're going to take a short break. When we come back, more of your calls at 800-433-8850 for this conversation about local forest and fauna. Do you regularly spend time in local woods and forests? What draws you to the great outdoors? Call us at 800-433-8850 or send us a tweet, @kojoshow, email to kojo@wamu.org, or go to our website, kojoshow.org. Ask a question or make a comment there. I'm Kojo Nnamdi.

NNAMDIWe're discussing local forest ecology with Nevin Dawson. He is an associate agent of Agriculture & Natural Resources and Forestry Stewardship with the University of Maryland Extension's Wye Research and Education Center. Bill McShea is a research ecologist with the Smithsonian Conservation Biology Institute, which is part of the National Zoo, and Kevin Sullivan is a wildlife biologist and the state director of Wildlife Services in Maryland, Delaware and D.C. for the U.S. Department of Agriculture.

NNAMDIWe got a Facebook comment from Paul in Sharpsburg. "People out here in Maryland complain about the deer in their yard. I say you're in their yard. They were here long before us." And, Bill McShea, we hear that a lot, but apparently, the explosion, expansion of the deer population has a little bit to do with our presence here, correct?

MCSHEAYeah, we're the one that made the world the way it is right now. This used to be all forest, for the most part, with just scattered openings. And deer are an edge species, and we made this world into one big edge. And then we populated it with corn fields and vegetable gardens and azalea bushes, so if you were going to come back in the next life as a deer, Virginia would be the place to do it.

MCSHEASo we can't really blame them for being so abundant because we've made a world that is perfectly suited for them.

NNAMDIHere is the other side of the comment. We got an email comment from Bailey, who says, "My son's North Berkeley, Calif. neighbor noticed that the herds of deer in their area had disappeared. They now have a mountain lion problem." That's not a problem we want to have, is it?

MCSHEAI'm skeptical. The more likely they have a problem with feral dogs or coyotes or -- I'm skeptical that they have a mountain lion problem. Deer...

NNAMDI'Cause deer don't have a lot of predators, do they?

MCSHEAVolvos...

MCSHEA...people, that's about it.

MCSHEAWe've gotten rid of most of the predators for deer because those were also predators on livestock. And, intentionally, they were removed from this ecosystem. And deer do come and go because of disease or habitat changes, and that's more likely than the mountain lion problem.

NNAMDIFacebook question from Leslie. "There seems to be a tremendous population explosion of rabbits in my suburban neighborhood. Could these cause problems?" Kevin Sullivan?

SULLIVANNot likely. I would say just enjoy them while they're there, but you may have to do some exclusion in and around some of your vegetable gardens. But if they're just sitting out in your front yard and eating dandelions, maybe they're doing you some help.

NNAMDIAnd this email question from Patricia in Reston. "Can you talk more about controls of Japanese stiltgrass in forest areas? My lawn is invaded every year from the stiltgrass in the protected forest area next to my property. The only method that I know about is crabgrass preventer applied early in April and again in July.

NNAMDI"While I can use these products on my own property, it would not be practical or allowed to treat the forest land." What do you say to Patricia, Nevin Dawson?

DAWSONYeah, that's right. That sort of product wouldn't work on a large scale. Usually, on a large-scale invasion of Japanese stiltgrass, you'd need to resort to some sort of herbicide spray. And there's a few options for that.

NNAMDIAnd, Kevin, you responded to the rabbit question earlier. Here -- as traditional habits for wildlife shrink or disappear, animals are finding new homes. So if I call you in a panic because I saw a fox in my backyard, as I did see riding up Nebraska Avenue one day, a fox -- red fox in somebody's front yard -- and I'd never seen one there before -- you would say what?

SULLIVANAgain, like the rabbits, I'd say enjoy it. Enjoy the wildlife. Keep your distance from it, but not every animal that you see during the day, a fox, a raccoon, is rabid. Not everyone is going to attack you. Those are very, very, very infrequent circumstances. So I would say enjoy the wildlife.

NNAMDIDeborah in Springfield, Va., you're on the air. Go ahead, please.

DEBORAHYeah, hi. I am presently a student in the Virginia State Master Gardener's program, and I've always been an avid gardener. We've come to find out that almost 95 percent of the invasive species that we and other gardeners have been planting, which affect all facets of wildlife, including the birdlife, are available at our local nurseries. They're not labeled invasive, and they don't give as much information to the average person out there.

NNAMDII'm seeing a lot of nodding around this table, Deborah. But go ahead, please.

DEBORAHWell, the basic question I have, in relation to the -- what I thought were just beautiful plants that are now, I know, invasive species, as well as plants that can take care of the erosion issues we have, especially now with all the flooding, what is up with the labeling at our nurseries? Is there a legislation, God forbid, or any information coming out to the consumer to support this good knowledge you're spreading now?

NNAMDIBill McShea?

MCSHEAWell, there's things you could do. One is make the company aware that this is an interest to you. You want to know if that plant is invasive or not. And if you start requesting about that, then they'll start labeling their plants that way. Secondly, there are websites that you can go to if you do your due diligence before you purchase these plants. There are websites of, these are the invasive species. This is what we're worried about.

MCSHEAAnd you can go to that nursery with a list in hand of species you want to stay away from. But I think pushing on the landscaper would be the best way to go, to let them know that this is a concern for you.

NNAMDIHere's Nevin Dawson.

DAWSONAnd I'm happy to report that legislation, I believe, has been passed in Maryland just recently to do exactly what you suggest, to label invasive species as such. It doesn't prevent most of them from being sold, but at least the educational factor is there. And I think there is also a shorter list of species that will be prohibited.

DEBORAHWell, I -- no. I really appreciate that. I seem to never hear Virginia's name on any of these to-dos for going forward, but I can hope, I guess.

NNAMDIDeborah, thank you so much for your call. And if we find out any more about what's being planned in Virginia, we'll be sure to let you know. Here is Alex in Fairfax, Va. Alex, you're on the air. Go ahead, please.

ALEXHi, Kojo. Thanks for a really great show, and your guests seem very knowledgeable. I just have a quick question. I've -- well, I've seen coyotes a couple times near my home in Fairfax, Va. and I know that they've been -- the population has been increasing in the area. But I was wondering whether coyotes originally or naturally live in the mountains of Virginia.

ALEXI mean, obviously, not so common in the suburbs, but I was wondering whether they were natural to our area.

NNAMDIKevin Sullivan.

SULLIVANCoyotes are native to the Northeast. They're native to Virginia, Maryland and D.C. and, to my knowledge, every county in Virginia, Maryland, and even right here in D.C., do have coyote populations.

NNAMDIAlex, thank you so much for your call.

ALEXThanks.

NNAMDINevin, a lot of people think the best thing to do is to take a hands-off approach and let nature run its course. They wouldn't dream of cutting down a tree or encouraging animals to gather in their backyard. But that isn't always best. How do people know when to take an active role in shaping their environment? And where do they start?

DAWSONRight. Well, the first step in that process is figuring out what your goals for the land are. They may not involve profit or income. They may not involve hunting. But you own the land for a reason. Even if it's because it came with the -- you know, it came on the property that your dream house was located on, you know, you can still get a lot of out that land. So let's take a wildlife habitat, for example. A lot of folks like to see wildlife on their land.

DAWSONThere are pretty small simple projects you can work on to help that along, brush piles, for example, in these areas where the understory has been removed through deer browse or invasive species, you can help restore the cover element that wildlife species require by building brush piles from branches and stumps. And even tires and old cinder blocks can be the bases for a brush pile.

DAWSONAnd then you can also plant tree species that provide food for wildlife, things like oaks and hickory or berry bushes. These are all things that can help encourage wildlife to visit your land. And the same goes for other goals, like just making your property look better, just the health of your forest and so forth. So that goal-setting process and then working towards the goal is really what we like to encourage.

NNAMDIAny suggestions, Bill McShea?

MCSHEAJust an addition to that is there are state programs for people who own grasslands or pastures. So converting to native grasses -- switchgrass, big bluestem, little bluestem, Indian grass -- those grasses that were native to this area, you can get involved with various state programs that help you do that conversion.

MCSHEAAnd those native grasses do much better with birds and pollinators than the European grasses that a lot of people have associated with their livestock production.

DAWSONYeah, and building on that, what a lot of people don't realize is that grassland and early successional forests -- so, basically, young trees -- are one of the limiting factors for a lot of native species. And, you know, our forests in Maryland, at least, are aging. They continue to age. And part of that is because folks aren't harvesting their forests as much anymore. There's a lot of reasons for that.

DAWSONBut if you have the opportunity to harvest a forest and create that meadowland or that early successional forest, that's a great opportunity to provide a habitat that is very infrequent and limited in our area.

NNAMDIHere is Lydda (sp?) in Great Falls, Va. Lydda, your turn.

LYDDAYes. Hi. I have a question. I live in Great Falls, Va. And about three, four months ago, at night, I saw -- you know, my sensors came on in the front yard, and I saw this animal. It's anteater with a long nose that -- it eats ants. It sticks its nose in the soil and eats ants. I just thought that was just unbelievable. I didn't think that we would have that in our neighborhood.

LYDDASo I want to know how common they are in Virginia, in our area, Great Falls-Reston area.

NNAMDIKevin, I just saw an article this morning indicating that we might be seeing more of those in this area.

SULLIVANTo my knowledge, those would be escapees, or those are someone that -- someone had them, and they were released. But you could call your animal control. But anteaters are not native to that area or anywhere in the area.

NNAMDILydda? Lydda, are you there? Oh, I guess, Lydda has taken our advice and is in the process of calling. Here we go now to Rosslyn (sp?) in Laurel, Del. Rosslyn, you're on the air. Go ahead, please.

ROSSLYNHey. I have noticed a lot of English ivy, and I see it's proliferating along the roads and kind of spreading towards state park. Lots of tree trunks are covered, and I just didn't know if you had any -- outside of pulling it up, is there anything else that you can do to get rid of it?

NNAMDINevin?

DAWSONYeah, pulling it up might work. It is able to damage mature trees, so I'd say the priority is probably to sever the vines on those trees. And you don't need necessarily to pull the vines off the tree, but just to kill the vines as they're climbing. And it's best to actually make two cuts so you can remove a chunk and be sure that you've gotten it all. Again, for large areas on the forest floor, an herbicide spray is usually the most effective thing.

DAWSONAnother technique that I've been working more with in the recent past is actually using goats for invasive species control. And they will eat English ivy. You know, it won't work in a lot of situations. Goats...

NNAMDIIs there anything they won't eat?

DAWSONThat's a good question.

MCSHEAThey haven't found it.

NNAMDII haven't found one. I haven't found it yet.

DAWSONThere are a few things. And you do have to be careful if you are going to use goats, that the site is really a good place for them 'cause they will eat native species just as much as invasive ones. So you want to make sure that it's mostly invasive species.

NNAMDIThank you very much for your call, and good luck to -- go ahead, please, Rosslyn.

ROSSLYNMy question is, do you have any documentation anywhere that says anything about getting goats or not? That might help.

DAWSONThere is a website, and I'm trying to remember the address. I think it's sheepandgoat.info, perhaps. It's a Maryland-based website, and it has a directory of sheep and goat producers. So you might try looking through that for someone in your area, contacting that person and seeing if they're interested working with you.

DAWSONThe great part is that while the goats are grazing and doing the work for you, they are still, you know, putting on meat and ideally helping the goat owners achieve their objectives at the same time.

NNAMDIWe're almost out of time, but time just enough for Cindy in Columbia, Md., to tell us what she and her husband saw. Cindy, you're on the air. Go ahead, please.

CINDYHi. I almost didn't call 'cause I know you guys are going to say I'm crazy. But when you had the other mountain lion call, I decided to do it. My husband and I live in Howard County, frequently walk in McKeldin Area of Patapsco State Park, and in July of 2008, at 7:30 in the evening, we did see a full-grown mountain lion in the park.

NNAMDIAnd, Kevin Sullivan, what do you say to that in 10 seconds or less?

SULLIVANI would say when you ever see anything like that, I would call your state agency, the Department of Natural Resources, so they can get out there and investigate it.

NNAMDIKevin Sullivan is a wildlife biologist and the state director for Wildlife Services in Maryland, Delaware and D.C. for the U.S. Department of Agriculture. Nevin Dawson is an associate agent of Agriculture & Natural Resources and Forestry stewardship with the University of Maryland Extension Wye Research and Education Center. And Bill McShea is a research ecologist with the Smithsonian Conservation Biology Institute. I'm Kojo Nnamdi.