Combating Invasive Species Impacting Michigan Forests

March 9, 2022

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Video Transcript

 - [Interviewer] But we're gonna be talking about forest management and specifically invasive species control and our impact of those species, invasive species, on our Michigan forests. We're gonna have Alex Florian. Did I get closer this time? Florian? - It's Florian, yep. - [Interviewer] Florian, okay. I'll get better at it. Thank you to the GreenStone Farm Credit Service and North Central SER Program and Mark Wolbers from the Alaskan Pioneer Fruit Growers Association that all contributed to helping us present, especially the close captioning, for the videos. So next up Alex is fairly new to his job, but his, has some experience over his years in, in controlling invasive pests here in Southwest Michigan. Alex, tell us what we need to know about invasive plants in our woodlots. - Yeah, so like I said, my name's Alex Florian. I work with the SW x SW Corner CISMA, which works to help with invasive species problems throughout Southwest Michigan in Berrien, Cass, and Van Buren Counties. I'll talk a little bit, a little bit more about CISMAs in a minute, but first I want to give everyone kind of an overview of what I'll be talking about. First, what is a CISMA and also what are invasive species. Then we're gonna spend most of our time talking about common invasive plants that we find in Michigan forests. And then also Michigan's watchlist species, which are invasive plants that aren't very common, but are really important to detect early. And then we'll spend some time on what you can do to help, your different management options, and then we'll take some time for questions. I think Deborah did a really good job covering insects at the beginning so I don't have any content about insects in here, but CISMAs do often work with, you know, insects, fish, anything, any invasive species. So first, what is a CISMA? CISMAs are Michigan's Cooperative Invasive Species Management Areas. So every county in Michigan is part of a CISMA. I'd like everyone to take a minute, look at your county, look at the map till you figure out what CISMA you're part of. CISMAs are really great for providing information about invasive species you might have on your woodlots as well as helping with identification if you're not sure what something is. CISMAs are really designed to address invasive species at the landscape scale by fostering partnerships. So, you know, we work with county and municipal governments, schools, scout groups, homeowners, lake associations. We also collaborate with the DNR EGLE, MDARD, basically trying to work with everyone and get everyone working in the same direction on invasive species. Michigan has 22 different CISMAs and 22 different ways to run a CISMA. So, you know, some CISMAs focus a lot on control. You know, a lot of the ones on the west side of Michigan on the shores of Lake Michigan are focused a lot on HWA. Other CISMAs focus a lot on invasive species in trade, like making sure we're not planting invasive species in, like ornamental gardens, that kind of thing. And it really just depends on what is most needed by their communities. So what services your CISMA offer can vary a lot. And I encourage you to reach out to your CISMA coordinator, figure out what, what they do in your area. Next, I think it's important to start with, like, what is an invasive species before we start talking about 'em? Invasive species are species that aren't from our area and cause harm to the environment, the economy or human health. So something like poison ivy, which is a native plant, even though it can harm human health, is not something that I'm gonna work on just because it's also a native plant. It's really important in the life cycles of some moths. And it is pretty beneficial to the ecosystem, but invasive species can be, yeah, so invasive species can be plants, animals, even fungus. This is a picture of oak wily, may or may not be invasive, but CISMAs will usually have some work involving it. But why should we care about invasive species? Like it's just another plant, right? Well, invasive species tend to displace native species and they don't provide the same ecosystem services. So if we look at this phragmiteous grass, you can all see my mouse, right? Yes, I think so. So if we look at this phragmites here, you can see it's incredibly dense, and there's no native plants that are growing in this stand. It's just phragmites. So what maybe used to be there was probably a really diverse group of native plants, which each does a different thing for the ecosystem and is utilized in different ways by native animals. But instead we just have this one kind of plant that's, according to some research, only used by maybe a dozen insects, well, when it's here in North America, but over in its native range is used by over 100 different insects. So it's really just not as useful to our ecosystem when it's invasive and when it's those big monocultures. Invasive species also tend to threaten agricultural products, infrastructure. There's one insect, spotted lantern fly, it's really prevalent in Pennsylvania, really slowly moving westward. We don't know of it in Michigan yet, but it's a real threat to grape crops and can really decimate those, which we have a lot of in my part of Michigan, but maybe not so much further north. Some invasive species can also seriously injure humans, pets, or livestock. There I'm thinking about stuff like giant hogsweed, which has a chemical on it, which when it gets on your skin and it's exposed to light can cause some pretty severe burns or something like swallow-wort which are a vine where, that is in some parts of the world like Canada called dog-choking weed because dogs or other livestock, they eat it and actually, like, choke and die. So invasive species, you know, that's a really broad range of effects, really broad range of problems. But we, we define them as species that cause problems, so they all cause problems. All right. So let's do some plant identification, the most fun part. So first we're gonna talk about multi-flora rose, which is this plant here on the right. Over on the left, I have some native swamp rose to compare it to cause they do look pretty similar. The best characteristic to tell the difference is if you look at the petiole, which is where the leaf kind of comes back and meets the stem, on the invasive multi-flora rose, it's gonna be fringed like this, where it's gonna be more longer and smooth on our native swamp rose. You can see it there like that. Next, sorry, we have Japanese barberry. This is a shrubby plant. I usually see it about this size on the ground, but in some really bad cases, I've seen it up like eye level. The best way to identify this is if you look at the leaves, they're this very teardrop type shape and all the leaves are different sizes. It also has these red berries on it, and it has these really thin little thorns that go along it, too. At the end of the fall, this will turn a really, like, deep reddish purplish color, which is why you see it planted a lot in, like, landscapes, but please don't plant this in your landscapes 'cause it will escape and it will start to grow up in your forests. Next, we have a autumn olive. The best way to identify this is if you look on the underside of the leaves, it'll be covered in these silver spots, but the whole plant is spotted, here up at the tops of the leaves covered in spots, the berries covered in spots. Again, this is a shrub, little bit taller. It can grow, you know, 10 to 14 feet-ish. It's usually how big I see it. Next there's garlic mustard. Garlic mustard can be tricky to identify because it's a biennial plant. So it has a two year life cycle. The first year, it's this short little leafy stuff just on the ground. But then the second year, it'll shoot up quite a bit taller and you can see the leaf shapes are, I think, fairly different. They'll be a lot rounder the first year and then more pointed on the second year. But the best way to identify it is this kind of leaf shape and the tooth-to-leaf margin. And if you're not sure, you always pick up those leaves, crush it and smell it and it'll smell like mustard. Hence the name garlic mustard. Especially good for the first year 'cause this does look quite a bit like a couple of our native plants. Next, Oriental bittersweet, which is a vine. I usually identify this just by how it grows up the trees. You can see this vine coiling around itself and multiple vines coiling around and you can see this tree ain't doing so hot because of, you know, all this vine matter crawling up over it. You know, you'll see in some really bad areas, the vines will be up all the way over the tree, just drooping over it. And it has these fruits that are covered in a yellow casing that later in the air'll break, open and reveal the red fruit inside. And then it also has this leaf that's pretty broad and comes to a point like that. Next we have tree-of-heaven, which you find in forests because it's a tree. Like most invasive species, you're gonna see this most on the edge of the forest where there's more disturbance. Most invasive species are really well-adapted to very disturbed areas. But tree-of-heaven, specifically, it has these really long leaves that you can see on this picture. They're compound leaves. So this is one leaf covered in these individual leaflets. Best way to identify it is if you look at those little leaflets, at the base of 'em, it'll have two little bumps. Whereas some things that look similar like sumac will be serrated all the way up. Another way to identify this is, again, by smell. If you grab those leaves, crush 'em up and smell 'em, it'll smell like peanut butter. Some people say rotten peanut butter. I think it just smells like peanut butter. Next we have privet. Privet is a genus; there's a number of different species in it. So they don't all look exactly the same. So you really have to be able to look for those key characteristics on it. For this, usually it's, you know, it's always gonna be very opposite so you can see the branches come off directly opposite of each other and then the leaves come off directly opposite of each other. As you go further up on the stem, the leaves will get bigger and then you'll see the berries or flowers or whatever reproductive structures always gonna be out on the ends of those branches. It's got kind of a wavy leaf margin too. It's a little hard to see on these pictures, But it's a little bit wavy. Next, we have Japanese knotweed. I have a coworker who describes Japanese knotweed as just having a general aura of destruction, which I think is pretty accurate. To identify it, you know, look at these leaves. They're pretty shield shaped. You can see the stem kinda zigzags back and forth between the leaves. Depending on the time of year, you might see these white flowers growing up out of it. And, you know, the stalks themselves are kind of bamboo-shaped. They're segmented like this. Japanese knotweeds are really interesting plant because it evolved originally in Japan in really volcanic areas where you get, you know, flows of lava coming down, covering the whole area in solid rock, but then Japanese knotweed just evolved to be the first thing to be able to break up through that rock and grow and get that nice open sunlight. Luckily, we don't have volcanoes here in Michigan, but we do have concrete. So you'll see this jutting up out of parking lots, out of roads, sidewalks, that kinda thing all the time. And so those are really just the plants that I see all the time when I am walking in the woods. But now we're gonna talk about some that you're probably not going to see, but if you do, it's really important that you tell someone. So these are Michigan's invasive species watchlist. So they're either not known in the state or they're only known in a couple of small patches and we wanna detect them early so that we can hopefully eradicate them before they can spread out and become a larger issue. Yep. The first couple of these are gonna be vines. First of all, kudzu. Has anyone here heard of the vine that ate the South? That is kudzu. You'll see pictures of this stuff in the South, just over whole landscapes, just draping all over everything, creeping, nothing but kudzu. Luckily, it hasn't gotten that bad in Michigan, but we do have a couple of patches. The best way to identify it is it'll have these leaves of three, a little bit like poison ivy, except a lot more lobe. So the two back leaves will have these two lobes and then the third middle leaf will have three lobes. It also has these purple flowers which, later in the year, come out to these really hairy beads here. Next we have mile-a-minute weed. Mile-a-minute weed is best identified by having the most triangular leaf you ever did see. You can see just very, very triangle-shaped. It's almost unnatural looking. They also have, you can see, thorns along the stems and where those stems branch off, there's little, you know, smaller circular leaves. But really if you just look at that triangular leaf, you're gonna figure out what it is. Next, we have Chinese yam. Again, we're gonna look at the leaf on this. You can see it's this really long heart-shaped leaf with kinda two chunks taken out the side. It also has these little brown tubercles. They're sometimes called air, air potatoes. Those can be a good identifying characteristic, especially in the winter when the leaves have fallen off. Those will still be there, and you can identify 'em that way. Next, Japanese stiltgrass. This one's pretty hard to identify just because most people don't notice it. It's a little grass growing right on the ground until it starts growing everywhere like you can see here. The best way to identify it is it's got these, this, you know, really thin, silvery mid-vein going down each of the leaves. Next, we have Japanese chaff flower. This one has like a green bottle brush shaped leaf you can see here, or a flower. There's no petals anywhere on this. And you'll see, you know, they'll come out kind of in a branching structure with a number of flowers per plant. Next, we have Himalayan balsam, which is, it's a member of the impatient family. So it's got this really impatient-shaped flower here. Can be anywhere from purple to white. I think the best characteristic on this is this really, really serrated leaf. Depending on the time of year, it might even be darker along that fringe there. And then it has these big wide hollow stems that it grows up in. So those are, you know, again, Michigan's invasive watchlist species. So now let's talk about some things you can do. We're gonna start with what can everyone do, and then I'll talk a little bit more about what land managers and people who have woodlots can do. The most important thing you can do is good decontamination. You know, cleaning your boots with 10% bleach solution before you leave a site makes sure that we're not taking invasive species from one spot and moving it to another one. Even if you didn't see any invasive species while you were walking, it doesn't mean the seeds weren't there. So it's really important to do this every time you're moving between sites. If you have, you know, large, heavy equipment, 'cause you're working on a project, it's also important to remove any dirt and plant material from that equipment. When you get home, take your clothes, throw 'em in the dryer, put it on high. That'll kill any hitchhiker seeds or insects or on your clothes. And remember that some decontamination is better than no decontamination. You know, if you go for a walk and you don't have a 10% bleach solution on you, it's still really good to take a brush and brush off your boots. That way you're getting most of that plant material off. Next thing you can do is report things to MISIN. MISIN is the Michigan Invasive Species Information Network. It's a really cool tool that lets us share data, share maps. You can go to or it can follow this QR code here to get the app for your phone. I would encourage everyone to do that right now while I'm talking but MISIN really lets us share maps across agencies. So CISMAs are putting all their reports in MISIN. The DNR puts a lot of information into MISIN. Anyone who's working on invasive species can do that. And then we can really get a broader picture of how invasive species are moving and what's in our area. You can also explore those maps. So if you're curious what's growing in your area, what's known to be around you, you can go on MISIN, take a look there. You can also report stuff, but if you're reporting one of those watch list species I mentioned in the second half of the plant ID, I really recommend you also send an email or phone call to EGLE or MDARD. Each plant has a different specific person you wanna contact, but getting those contacts through MISIN and that way really lets us make sure we're catching it and not, you know, missing something in a miscommunication or anything like that. So next, we're gonna talk about what can land managers do. So this is if you have a woodlot. And if you have an invasive species and you're looking to manage it, the first thing you're want, gonna wanna do is find some best management practices. I always start with Every invasive species has a page on here, all the ones in Michigan do, and it'll have some good identification information, some pictures, if it's a watchlist species, there'll be some contact info at the top to record it. But if you scroll all the way to the bottom, there'll be a link to some best management practices that really tell you how to manage that invasive species on your land. Not every species has a BMP for Michigan. They take a lot of time and work from the state agencies to put together and to make sure they're accurate. So if you can't find one on, you can always just Google the name of the species and then BMP. I would still look for one written for the upper Midwest or whatever region you're in. Also try to find one that's fairly recent, you know, ideally within the last five years, but the more recent, the better, just because as new research comes out, a lot of these management recommendations are changing and we wanna make sure we're using the most up-to-date information. Also, if you're using a BMP from outside of the area you live, be aware that regulations will often differ, especially concerning pesticide use. And you wanna make sure you're following the laws where you live. Next, if you have a pesticide certification, you probably already know about integrated pest management, but for those of you that don't, this is kind of the framework we use when we're thinking about invasive species management. So the first and most important step is just to be out monitoring and be able to identify those pests. So get out in your forest, know what's there. And then if you see something you don't recognize that hasn't been there before, that should set off some alarm bells, start to identify that, figure out what's going on. Then we usually set action thresholds. So especially if you're just growing your woodlot for, you know, timber harvest, you might be able to tolerate a little bit of invasive species. But you need to set a threshold. Like, at this point is when I'm actually gonna go out and do some work. That way we're, you know, not going out and doing work that doesn't need to be done, and we're not, you know, especially not spraying chemicals that don't need to be sprayed at the time. Then it's important to take preventative measures, especially things like those decontamination procedures. I talked about earlier, just taking steps to stop the invasive species before they show up. And then eventually, you know, if that invasive species gets above the action threshold, do whatever control method is recommended by the best management practices you found. And then you repeat, you go back to monitoring. It doesn't make any sense to do a management thing, like go out and do a spray and then not watch it to see how well it worked, you know. 'Cause if it doesn't work and then you see it again, you wanna know that it didn't work so you can try something else. And if it does work, you wanna know when it worked. You know, what time of year it worked well so that you can repeat that and hopefully see that same success. Now I'll talk about a couple different methods that we use for invasive species management. The number one thing people usually go for is either pulling or mowing their invasive species. So they think, "Oh, I cut it down, "it'll be gone," and that can sometimes be effective, but it also sometimes makes things worse. So I've got a picture here of a big old pile of garlic mustard. Pulling garlic mustard is a really common management action. Seems to be fairly effective. But if you were to pull, you know, some other invasive species like Japanese knotweed, you're actually probably gonna make it worse. 'Cause it'll, you know, notice it's getting pulled, it'll shoot roots out further and grow up elsewhere. Next, we at our CISMA have a strike team that does a lot of cut stump treatments. So we'll take a brush cutter, you know, basically a weed whacker with a saw on the end, and cut down the invasive species. And then we'll paint a little bit of herbicide on those stumps to make sure it's getting drawn down into the roots and killing it. This lets us really minimize the amount of herbicide using, minimize the amount that's going on in the landscape and really lets us target those invasive species specifically, not all cuts requires an herbicide and you should always make sure you're using one that's approved for the situation you're using it in. Last, we have injecting, Deb showed off some injecting earlier that works for trees, but we can also do injecting for some invasive plants like Japanese knotweed. As I mentioned earlier, it has these like long bamboo-like sectioned stems, the bottoms and tops of these sections are, you know, walled off on the inside. But then there's a hollow section in the middle. So you can just take an injector, stick it in there, spray some herbicide, and it'll pool in that section and slowly be drawn into the plant, which is a really good way to eliminate the risk of drift, eliminate the risk of off-target application. It's like individually putting it into each plant. It's also pretty labor intensive though. So we usually don't recommend this for more than, you know, 100 stems of Japanese knotweed. Yeah. And lastly, it's important to remember that in management on its own is not usually that useful. Invasive species management is part of a restoration effort. So if you go and pull out all the invasive species, you get 'em all dead, they're all out of there, and you just have a big plot of bare soil, you are either going to get a bunch more invasive species or just a bunch of erosion and that's gonna be bad too. So it's important to under, first of all, understand your seed bank. So before you go in, this is a technique one of the land conservancies, Southwest Michigan Land Conservancy, that I work with does is they'll go take soil cores in the area they're trying to restore, throw 'em in a pot, add some water and see what grows, and that'll let 'em know, you know, is there a good bank of native seeds underneath these invasives? Or are we just gonna get more invasives and we need to be ready with a, you know, a seed mix to put out to encourage that growth. Yeah. I wanna say thank you to the team at MSU Extension, putting this on and also to the team at for their huge and wonderful library of pictures. And I think I talked a little fast, so we have plenty of time for questions and we should have time to get to lunch on time. - [Interviewer] Yeah, Alex, we've got some time for questions and the way, if you're one of those participants, type those into the Q and A, and we'll get them to you. First off, I got a couple questions here that sort of go in the area of telling the difference between Oriental bittersweet, Virginia creeper and wild grapevine. - Yeah. - And then a little bit, doesn't matter, are these all things that have to be controlled? - Yeah, so I'll start with the Virginia creeper and grapevine. Virginia creeper, I usually see it growing around the tree, whereas the bittersweet is growing around itself. And then for wild grape, I think the best way to tell it apart is the bark. Wild grape has this really kinda flaky bark. It almost looks like, like a shagbark hickory but as a vine going up, whereas Oriental bittersweet has a much smoother bark than that. And what was the other question? - [Interviewer] Well, I, I think it's, even though the Virginia creeper and grapevine are, are not invasives, are they also things that we would control in the same manner or want to control? - So that can depend. Any, you know, any species that's growing up into a monoculture can be a bad thing. It may be necessary to thin out those other vines if they get really bad, especially grapevine can grow really, really big, but usually if that's happening, it's because the area's highly disturbed and you wanna focus, I think, more on the disturbance that's allowing all of that extra growth and overgrowth. - [Interviewer] 'Kay, good. So probably the, the one that's what about European swamp thistle? - I'm not aware of European swamp thistle. That's definitely something you would wanna reach out to your local CISMA coordinator about. They can give you some more information. I don't wanna talk about things I don't know about, so. - Okay. - Yeah. - [Interviewer] Back on control, so earlier Dr. McCullough talked about control with either some type of bark treatments, those types of things. Do you, most of the programs you're working with, you're providing the control, correct? - So our CISMA has a strike team that goes out and does management in some pretty specific areas. And then we also help provide landowners with specific recommendations for their property to do themselves. Does that answer the question? - [Interviewer] Yeah, but I think specifically is, is cut stump herbicide treatments effective in the summer or you do you need to wait until fall? - So one of the things that's really important with any invasive species treatment is the time of year and making sure you're doing the right treatment at the right time. For cut stump, it's gonna depend species to species. And you're gonna wanna look into what specific invasive you're looking at and when it's most useful. Most of the time it is gonna be that fall-winter when the plant is drawing nutrients back down into the roots so that hopefully it takes the herbicide with it. But there are some cases in which it's effective in the spring as well. - [Interviewer] So there's a couple questions in here about autumn olive. They go, they go the gamut from did, do we know that autumn olive berries are edible? - Yeah. - and, and then there's some questions here about autumn olive is one of the worst things they've ever seen, so. - Yeah, so autumn olive berries are edible. I usually don't mention that because if you start eating invasive species, you're becoming a vector for those seeds, wherever, you know, it goes in one way, it comes out another way. Hopefully, whatever sewer system you're using, those seeds end up getting treated, but that's not always the case. And we don't like it when people are spreading invasive species through any means, but they are edible, if you want to eat them. Yeah, autumn olive can get pretty bad. I've seen some pretty, pretty thick stands of it. - [Interviewer] So yeah, yeah. Unfortunately, that's something that a lot of people acquired over time and has spread, definitely. Question about burning cuttings from poison ivy and other things. And I think what we're dealing with here is they're worried about the concern over poison ivy fumes being toxic. - Yeah, so some, some invasive plants have, you know, those poisonous chemicals that you don't wanna burn. I think usually about like poison hemlock and giant hogsweed, really don't wanna burn those and aerosolize those chemicals. If you look up, there is a document from EGLE on invasive plant disposal. That's really good for a lot of invasive species. Unfortunately, the best method is to double bag it in a plastic trash bag and send it to a landfill because composting can sometimes give those plants a vector of spread, just leaving it on the ground, in some cases they'll reroot. So, you know, unfortunately more plastic and send it to a landfill is often the recommendation. But again, that depends species to species. - [Interviewer] Yeah, we, we, a lot of times, we don't think about burning firewood that has the vine, the poison ivy vine's mixed with it and that type of thing. - Yeah. - [Interviewer] And very, very easy to carry that toxin into - Yeah. - [Interviewer] Someone's lungs. - Yeah. - [Interviewer] So we talked about winter treatment, fall and winter treatment, from stump treatments. Is there a best time of the year to do basal treatment or cut edge treatment? - I'm not sure off the top of my head. It's probably, again, gonna depend. Specific on the species. It's specifically on what you're applying. Yeah. - Probably the best thing is to go back to the labels. The most of the stump count - Yes. - [Interviewer] treatment stuff has a pretty specific label. - Yep. - I know around the farm, we, we tend to go to the products that have a chart specific to the species that you're trying to control. - Yeah. - [Interviewer] So, any other questions that we have out there? So I see the last slide here has a way, an email address, to get back to Alex if there's - Yep. - [Interviewer] any questions. Your phone number is the same as the conservation district and-- - Yep, I work outta the Van Buren Conservation District. - Van Buren? Great, and then what other programs are, are invasive species control in southwest Michigan beyond your corner program? - Yeah, so there are a lot of, you know, private contractors, independent contractors that do invasive species management for private land. Most of those, usually if you get in contact with your CISMA coordinator, they're gonna have a list of contractors that they can send you. The state, you know, the DNR has initiatives that take place on state land. Some road commissions are really good about treating invasives in the rights of way on the roads. Other road commissions are less good about that. Same kind of thing with drain commissions. That varies a lot county to county. Yeah, unfortunately there's not, like, a lot of people out doing invasive species work. - [Interviewer] So there are other CISMAs beyond yours in your three county area? - Yeah, so I, let me go back to that slide. - Yeah. - So every, all the way in here, every county in Michigan is part of a CISMA. If you're outside of Michigan, there are a lot of areas with CISMAs. I think they were originally created out in Idaho to deal with all the federal range land out there, but you'll see different levels of coverage in different states. In Michigan, if you go to, you'll be able to find contact info for whatever CISMA you live in. - [Interviewer] Tremendous, I think that's a good place to I, to end. - Yep. - I don't see any additional questions. If you have-- - So I'll just say, your local conservation district probably also has resources that could help. - Okay, great, thank you.