asian jumping worms: what we know (2018 interview), with uw-madison’s brad herrick

I GET A LOT of questions about invasive species, and lately a week doesn’t go by without at least one asking what to do about so-called crazy worms or Asian jumping worms, which more and more of us are alarmed to be finding in our garden soil. I sought a researcher’s perspective on this really challenging and frankly terrifying pest.

Brad Herrick is Arboretum Ecologist and Research Program Manager at the University of Wisconsin-Madison Arboretum, where the staff first noticed the destructive handiwork of Asian jumping worms in 2013. He’s been studying them ever since. Though our understanding of these organisms is in the very early stages, we talked about their biology, their impact, and what control tactics are being explored by scientists seeking a solution. (Photo of Brad, below, by Eric Hamilton, UW Communications.)

Update: In 2019, a year after this introductory interview, I got updates from Brad on research into the impact of heat on the embryo-filled cocoons that contain next year’s worms-to-be–that may in time help lead to answers in some situations. That newer story includes corrective tactics you can try to reduce the population if your infestation if limited to a small area of a garden. Read it here for even more information.

Read along as you listen to the March 19, 2018 edition of my public-radio show and podcast using the player below. You can subscribe to all future editions on iTunes or Stitcher (and browse my archive of podcasts here).

asian jumping worm q&a, with brad herrick



Q. You must have encountered a lot of different issues as an ecologist. Where does this rank? Is this pretty startling one?

A. Yes. It’s definitely right up there, and it’s one that was right under our noses, but we didn’t realize it until like you said 2013. My background is in plants, so I didn’t know a lot about earthworm. I definitely didn’t know different types of earthworms. We discovered it in 2013, and from then on out, we’ve been on a campaign to learn what we can and help others learn as well what to look for and some of the impacts.

Q. To just kind of backtrack: Of course, gardeners were always taught earthworm equals good because they aerate the soil and blah-blah-blah, and leave behind rich castings and so forth. But things are really changing. You said you didn’t know a lot about earthworms, but I bet you do now. These are kind of the latest invasives, but in the northern United States, especially, we don’t really have a lot of native earthworms, do we, of any kind?

A. That’s correct. Pretty much anywhere that was glaciated during the last glaciation, depending on your latitude around 10,000 years ago, or so are pretty much devoid of any native earthworms. Here in Wisconsin, all of our earthworms are most part European species and more recently this new line of Asian species.

Q. You knew you had earthworms, of course, always at the Arboretum, but you didn’t know you had these Asian species. What was the moment? I can tell you the moment that I experienced when I had this “aha,” but what was the moment for you? What was it like? What was the tell-tale sign?

A. It was interesting. What happened was that we were a site for a conference. It was called the Society for Ecological Restoration conference; they were here in Madison. We held a field trip for folks. We had some help from the DNR [Wisconsin Department of Natural Resources], from their earthworm biologists. We came out and talked about invasive species in general and mostly about plants, and she gave a short talk about invasive earthworms.

We actually went out one of our wooded sites here at the Arboretum, and dug around for folks, to show them what European earthworms look like, and talk about what they can do to the leaf litter and the soil and the structure and the plants.

She mentioned just kind of offhandedly that, “Oh, yes. We also had this new group of earthworms from Asia that we don’t have in Wisconsin yet. They’re just kind of … You know that they’re around. We think they’re going to be a really big problem. We’re really working hard to keep them out of the state.”

Not a minute later, she wiped back some of the leaf litter. We saw maybe half a dozen of these snaking, squirming, wiggling earthworms that had a really weird behavior.

Right away, she said, “Oh my gosh. This is what I was just mentioning. This is the new Asian earthworm that until just now I didn’t think we had.” [Note: The Asian species of concern so far are Amynthas agrestis and A. tokioensis, plus Metaphire hilgendorfi. The first two are the ones that have been studied to date at UW-Madison.]

That really kicked off everything. Since then, we’ve been working closely with our Department of Natural Resources, garden clubs, Master Gardeners, other folks from other states, academics, to learn what we can and do as much outreach as possible.

Q. I think what’s scariest—and I mean, of course, all invasive species, whether plant or insect or another organism, a pathogen of some other kind—they’re all scary when we hear about one or another. But a lot of times, they’re specific to like a species or a genus, but often a species or a couple of species. So that’s horrifying enough, like Emerald Ash Borer or whatever.

But this is like it’s a pest of the precious soil that all plants rely on and therefore we all rely on. This is in some way … this pest freaks me out in a way that … not to say that we could necessarily say oh what’s the worst or better grades of bad, but because this attacks the soil. I wonder if you could just talk about that: the mechanism that’s going on that throws things out of balance because again we all thought, oh earthworms were good. They deposit these castings.

But these guys, they live in big congregations and they go too fast; they do the work too fast. What happens?

A. That’s a great question, Margaret. As you said, for a long time—for decades and decades—we’ve been taught and gardeners have known this that earthworms are supposed to be good for your soil especially for your gardens, urban garden. That is true for a specific group of earthworms and in specific types of gardens.

For example, the European Nightcrawler, that everyone knows about. Those actually are really good at aerating the soil because they create these deep pore spaces. They mix the soil. They create channels and tunnels in the soil so that water can get to the roots, and it can really break up what can be often compacted urban soil. It can really help plants grow in a garden setting.

But what’s really different about these suite of species that are primarily from East Asia—the Korean Peninsula and Japan, is where they’re endemic to—is that most of them, the ones that we have now in North America, do not burrow down very far. They spend their entire life cycle in the top few centimeters of soil.

They’re not providing any of those deep-dwelling benefits turning the soil over, mixing nutrients—they’re not doing any of that. They’re doing all their work in a very small space in the soil profile, on the very top, and they do it quite well. They do it very well actually. They turn. They eat all the organic matter, as much as possible, using the form of leaves or whatever organic matter you have on the top of the soil.

They consume that. Then, like you mentioned earlier, they produce casts, which are their poop. And those casts are really rich in nutrients, and that’s usually a good thing for gardens, but what happened is they produce it so quickly, and they make available those nutrients so quickly, that it’s often lost to the plant because after the next rainstorm—those nutrients are leached away. It’s kind of like if you think of a quick-release fertilizer, a lot happens right away. It happens too fast for the plants to a take advantage of it. You end up with soil that actually has less nutrients in it and that can affect plant growth and plant establishment.

Q. I’ve read in the last couple of years, since I first learned about these worms, that they are not only in the Midwest. I know like a number of states or Minnesota, I think, Wisconsin and Michigan. I don’t know which other states have a problem with them. But the Southeast, the Smoky Mountains park. In the Smoky Mountains, they have an issue with them. In New England, we have increasing reports of issues with them.

I’ve read especially in the Great Lakes Forest, they can actually create almost like, I’ve seen referred to as “tree root gingivitis,” like where they destroy the tilth—I don’t know what you’d call it—of the soil, and stuff can’t even hold in the ground. Like they’ve wasted all the organic matter so quickly that the succession plan of these natural areas like in the Smokies or the Great Lakes is not happening like, even in native areas. Forget a garden. It bad enough that a garden is being destroyed, but these natural areas too, yes?

A. Right. For the Wisconsin Department of Natural Resources, that’s really their big concern is what can we do to keep these critters out of our national forests or nice, pristine state forests. You’re right. That’s what’s happened with the European earthworms, too. People don’t think of European earthworms or as earthworms as being that bad, because they’re everywhere. They’re ubiquitous. You find them in your backyard, you find them in forests. But again, there were glaciations and the Great Lakes for the most part—although these states were almost entirely glaciated—the plant communities that came back after those glaciers receded evolved without any presence of earthworms.

It’s a disturbance in the ecosystem. You’re right. These earthworms whether they’re European or Asian variety, they will literally consume the duff layer, which is that organic, spongy, highly nutritious layer that plants need especially when they’re germinating and getting established, and they’ll get rid of it. It’ll end up going right down to the mineral soil. You’re really left with very little nutritious soil that can hold roots and get plants started.

Even trees have problems when you reduce that buffering spongy layer, and you start to see buttressing roots. There is a lot of research now on the feedback between when that disturbance happens. It often opens the pathway for a new and basic plant like garlic mustard buckthorn to come in. It’s sort of a vicious cycle that once you have a real major disturbance: Native plants tend to get excluded, and the same with native soil biota. That’s been shown in the Smokies as well, that some of the native arthropods don’t do well in the presence of especially these new group of earthworms.

Q. It’s like what’s left of the soil is just its mineral content. Is that correct? Because the organic matter is gone.

A. In the high-abundance area, the high earthworm areas.

Q. They really waste the soil, and compared to much smaller organic-matter processing creatures—whether microbial creatures or even small insects, the guys that are sort of detritivores, or debris recyclers, in a forest community—these are big, hungry, fast-moving, fast-processing guys. As you said, they’re taking that duff layer all those years of fallen leaves that were meant to slowly decay and be crumbled up and have little organisms worked on them gradually. It’s not happening. It’s just being voraciously consumed and wasted quickly.

A. That’s right. They’re really good at what they do. We’ve done some research recently that’s shown that they not only consume that organic matter, but they can also move quickly between years.

Q. Oh!

A. They can spread into uninfested areas, and they can out-compete or displace other earthworm species, even if there are other non-native species like European species. They have not only are there hungry critters, they’re also very good competitors in other ways. We don’t know what the mechanisms are for how they displace other earthworms, or what that might mean long term. We just don’t know a lot yet about the suite of species. That’s some of the work that we’re doing here at the UW-Madison Arboretum.

Q. Sometimes for me in a garden setting, I wasn’t looking under the leaf litter like your colleague at the Department of Natural Resources who came on that tour and discovered them, but what I noticed was what looked almost like mole hills of coffee ground-like soil particles. Do you know what I mean?

A. Yes. Right. Some of the European earthworms like I mentioned, the deep-going ones, will create these little midden piles are called.

Q. Middens, right.

A. Middens. Yes. If you’re seeing little piles of soil often with kind of skeletal weave stuck in them, those are going to be European species. Those will not be the Asian species. But if you see more of a uniform coffee-ground-like soil signature, very loose and granular, that is a telltale sign that you have this other Asian variety.

Q. All around the edges—yes. That’s what I was seeing like the edge of beds, for instance. Instead of seeing those little piles like you’re mentioning that I had known in the past from time to time, it was like at the edge, there was just coffee grounds coming out from where the turf met the bed.

A. Yes.

Q. It’s really weird. When I lifted it and I looked, they were these snake-like worms. Their movements were more snake-like, and they were big. They’re so destructive anyway. Before I just keep complaining and complaining….[laughter]:

So your research at the Arboretum—how do ecologists such as yourself and other researchers, how do you even all sort of get together and say hey this is what we need to do, this is what approach we’re taking and our colleagues over here are going to take that approach. Who’s looking into what? What do we do?

A. For us, our first step was, O.K., we’ve found these critters here at the Arboretum. Where exactly are they? We did a mapping effort, the first spring, just to kind of know what we were working with: the scale of the infestation, the habitats. Then, we kind of worked with the systems that we could. One of the projects that we just got published in the journal of Biological Invasions was a study looking at we had an earthworm invasion and some of our sugar maple dominated forests.

We wanted to track them, track the spread in these forests, and to see what kind of impact they had on the plant communities, on things like soil pH and litter depth and these sort of forest-floor variables. This was actually a master’s student project by Katie Laushman.

What we found in that study was that in two years, we couldn’t really detect any marked changes in the vegetation. I say that with a caveat: that could be because of several reasons. A, there weren’t any, and it’s a real thing; that they’re not affecting some of these woodland plant species. Or it’s a new invasion and we just haven’t studied it long enough. Or the forest also have European species that have been here for a long time and might have already sort of done the damage to the plants that are going to be affected—that these aren’t going to have much more effect.

There’s some caveat there, but what we did find was that they spread in one year about 13 acres by themselves.

Q. Oh, wow.

A. If you think of a football field, it’s about 1.3 acres. That’s quite a lot just for a little earthworm. They also found out that they pretty clearly are displacing other earthworms. Basically, very few plots had both European and Asian. They move in, and other species move out. We’re going to be tracking this long-term just to try and ask other questions about their long-term effects versus short-term effects, litter depths and other soil properties. But that’s one part that we’re working on.

And then just kind of quickly, other projects that we have going on, we have a postdoc that’s looking at how do these critters affect tree hydraulics? How do they affect, for example, the ability of sugar maples—which is a really common tree, obviously—to take up water and nutrients to the roots? A pretty straightforward question, but obviously given how common sugar maple is, that could have ramifications for a lot of our hardwood forests.

Then, a colleague of mine, Marie Johnston, and I are looking at things that sort of dive into the control aspect: Are there things that we can figure out about the life cycle of this earthworm that we can disrupt that might control a population?

We’re specifically interested in the cocoon stage, which is the ones that we have in North America, the earthworms are annual species. They hatch from cocoon, which are little eggs were about 2 millimeters across. They hatch in the early spring, mature throughout the year. Then, when it gets to a certain temperature threshold, usually the first hard freeze, that they’ll die, but the cocoons will survive winter and then hatch again in the spring.

We’re trying to think about are there abiotic factors that might limit the viability of cocoons, of the embryos in the cocoon. We’re testing heat treatments. We’re testing things like flash-freezing, and trying to think of it other ways that we can disrupt a part of the life cycle that would offer some kind of control that either landscapers could use, or composters or even backyard gardeners, to apply a heat treatment and use in a small scale.

Q. As gardeners, what do we do? I think one thing we do is that most of the Cooperative Extensions or university extensions in areas that have these are interested in hearing if a homeowner has an outbreak of them. You want to know where they are, right? [Above: jumping worm field guide from Wisconsin DNR.]

A. Absolutely.

Q. We should report it. We should communicate with our Cooperative Extension [or state Department of Environmental Conservation or Department of Natural Resources]. I found that that’s happening everywhere.

I’ve read about, we could … I’ve read crazy things like put them in plastic bags and let them cook to death in the sun and then put that in the trash and things like that, but there’s a lot of them and like you said, they’re moving 13 acres.

When I first read about them a few years ago, I thought, well, golf-course managers, they’ve always hated middens on a beautiful putting green. They’ve always experimented mostly with horrendous chemicals in the years past, but nowadays, it’s more green. They’re looking for green things. I read that they were using something that came from the camellia plant, like a fertilizer, but I think came from the tea plant (which is a camellia), and some kind of fertilizer made with that, but it was only available commercially. But maybe now it’s available for homeowners. What avenues of control like that are you exploring?

A. This summer actually, we’re going to be doing some trials on a product that is sold under the organic label. It’s basically a very low Nitrogen-based fertilizer, but also has, like you say, extracts from tea seed oil.

Q. Tea seed. Right.

A. Yes, which has saponins, which is basically a toxin that plants produce. Actually, some of those studies—many of them were from Kentucky golf courses—have shown that they this fertilizer with these saponins does greatly reduce the number of midden piles or castes that earthworms create, meaning that they’re diminishing the population of earthworms.

There hasn’t been a lot done on the Asian species yet and that’s something that we’re interested in looking at is using a liquid version of this product or a granular version and coming up with what are the sort of minimum dosage that you would need to maybe reduce the population or get rid of the population—and also more importantly even what are the potential side effects, what are the impacts to other beneficial soil biota?

Q. Right.

A. That’s really important, I think, before we start to encourage folks to use one or the other controls. There is not a lot of research yet. We’re all for people trying things, but just know that there are often with it with controls, it’s going to control one thing, but it’s going to hurt something else, benefit something else. There’s always other factors than just the target species. But that’s something that we’re definitely interested in.

Q. I think biochar is another thing, because if it’s like sharp edges or something. It’s another thing it’s going to be explored. Is that another one?

A. Yes. There’s not much in literature on that. I don’t know a lot about biochar as a control, but I’ve heard that as well the physical properties of the biochar,, especially the small granular one that had really sharp edges can physically be destructive, the earthworm body, which obviously doesn’t have much of the hard shell on it. That is an option. Obviously, it’s a common soil amendment anyway that many gardeners would use. It’s an easy one to obtain. But yes, we’re also interested in as well.

Q. Brad, it’s early stages. It’s not that you don’t have the answers—it’s that there are no answers yet because you’re at the forefront and colleagues at other universities around the country that are being affected similarly doing this groundwork study. These are the beginning studies, right?

A. That’s exactly right.

Q. You’re going to come back and tell us what happens …

A. Absolutely.

Q. … along the way because we all need to learn together. I’m so appreciative for you giving us this 101 and telling us kind of where things are at about these Asian jumping worms, the latest invasive that I’m worried about.

more about invasive worms

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MY WEEKLY public-radio show, rated a “top-5 garden podcast” by “The Guardian” newspaper in the UK, began its ninth year in March 2018. In 2016, the show won three silver medals for excellence from the Garden Writers Association. It’s produced at Robin Hood Radio, the smallest NPR station in the nation. Listen locally in the Hudson Valley (NY)-Berkshires (MA)-Litchfield Hills (CT) Mondays at 8:30 AM Eastern, rerun at 8:30 Saturdays. Or play the March 19, 2018 show using the player near the top of this transcript. You can subscribe to all future editions on iTunes or Stitcher (and browse my archive of podcasts here).

  1. Alissa says:

    Many thanks for continuing to cover the jumping worms! I hadn’t heard the estimate that they’re moving 13 acres a year – wow, wow, wow. That’s crazy! I live about a mile from where the they found them in the Madison Arboretum in 2013 and only identified them in my yard last year, but I suspect they must have been there earlier and it took a while for the soil to show the characteristic coffee ground changes.

    As a result of the worms, I decided to mulch heavily this year with arborist chips to help keep the soil in place. Once the soil has been replaced by the coffee ground castings it seems to wash away incredibly easily. It surprises me that they aren’t seeing changes to the vegetation in the area, since it seems like the soil is no longer holding moisture as well, either.

  2. Cortney D says:

    I’m in Wisconsin too, Northwestern part. I know they are in our region but haven’t see any evidence of them in our yard yet. It feels a bit like awaiting your doom, knowing their arrival is imminent, but not knowing when or what to do. I’ll be very keen to hear how the new trials go and hopeful that they can find something that will work on them. Great interview!

  3. Jen T. says:

    Good, informative interview! I’m wondering if anyone has looked at what happens in an area with the jumping worms if there are also chickens (or guinea hens)? Chickens voraciously eat worms, but only get the ones on the surface and just below the soil line where they dig, which sounds like the habitat of the invaders.

    1. Liz says:

      I was thinking the same thing about the chickens. As soon as a worm is visible in my backyard soil my flock will find it.

    2. Martha says:

      I fed some large jumping worms to a friend’s 2 chickens in Evanston 2 yrs ago and it was hilarious watching them try to get them down…the large ones (Metaphire hilgendorfi) are fat, 6+ inches long and quite acrobatic. In the end the chickens won.

  4. Dan Gallagher says:

    This has to be the worst article about the Crazy Worm I have ever read. Cindy Hale at the University of Minnesota found them in 2003-2004 and your expert finds them in 2013 after the citizen scientist powered Great Lakes Worm Watch has been in existence since 2001. A link both to Cindy Hale, she is now at Cornell and The Great Lakes Worm Watch.


    By the way tell your expert The Canadian Nightcrawler is Lumbricus terrestris and The European Nightcrawler is Eisenia horentis. Although Lumbricus terrestris did originate in Europe it is still known as The Canadian Nightcrawler. The Jumping Worms are in the Amynthas genus.

    As gardeners hopefully everyone realizes the wondrous benefits of having earthworms working your soil. Their castings suppress soil borne diseases, aerate the soil without disrupting the microbiology. There castings are 3x to 7x loaded with plant form available nutrients than the surrounding soil. Charles Darwin Treatise on Earthworms was more anticipated than his Theory of Evolution at the time and its relevance is just as important today as we begin to garden more microbiologically. Sometimes you have to go small to get the big picture, Go ask, Alice.

    i do not like Chicken Little science. I just want the facts and sometimes we don’t notice things until they are gone, such as forest litter. There is research that The White Tail Deer may also have a hand in the disappearing forest litter.

    Any organism in abundance in the wrong place is similar to a weed and the irony is somehow, someway we are probably responsible for both either because of our ignorance or another lame attempt to one up nature.

  5. Patricia H Lintereur says:

    Alarming information! I will keep my eyes open in my gardens up here in N. VT. Love the idea of chickens and guinea hens. I was thinking the same thing. Put the birds to work!

  6. Steve says:

    This “sky is falling” stuff is so nonsensical. What is the goal, to reproduce ecosystems from 10,000 years ago? Doesn’t that strike you as more that a little bit nuts? You should interview Dr. Peter Del Tredici of the Arnold Arboretum about invasion biology.

  7. David says:

    Surely someone has studied this creature in its native environment and is familiar with its effects and natural controls there?

  8. De says:

    Some sites (like from NY state) say to pour a mustard and water mixture on the soil to drive worms to the surface so they can be discovered and disposed of. The mustard apparently irritates them. Do you know if Mr. Herrick has thoughts/info on that method? Thank you!

  9. Virginia says:

    I have a huge patch of backyard that is now devoid of even weeds! It has a kind of coffee ground consistency as well. Could I have imported them to Indiana by buying a plant from a nursery? It keeps growing every year. Is there anything I can do?

  10. R Wright says:

    My question is how do the experts think they got there in the first place? Foreign imports of ornamentals (plants) by the nursery industry, or an individual brought a plant back from a trip? Seems like those cocoons could hide in the potting soil, and no one knew it.
    With that knowledge, what is being done to prevent the spread of the Asian Worm to other, far-reaches of the country – such as the South, or West Coast or even Islands, like the State of Hawai‘i, where it would be devastating? It seems like red flags should be going up across the nation, especially in our ”bread basket” farm areas.

    1. Marian Whitcomb says:

      Good question! The problem is there are powerful forces such as people who make their living off moving plants and animals around, as well as people who are determined to foster the idea that humans know enough to simply engineer new ecologies without understanding the existing ones. They will try to obfuscate the issue, reject the preponderance of science, and pretend that humans, crops, food animals, and pets, are the only species that matter. These are the ones who will try to debunk a pile of mounting evidence that worldwide declines in many plants and animals is a result of ecological “short-circuiting” caused by humans introducing species at a phenomenal rate never seen on the planet before via planes, ships, automobiles, and the internet. They don’t want to change their business model or embrace the complexities of this problem, so it is easier to try to say it does not exist. I am guessing most of these people have never spent time in a pristine natural place enough to understand its wondrous complexity. Everyone should look at the National Geographic magazine from January 2018 to see that invasive plants and animals have had substantially more negative impact on birds than even climate change! The same thing is happening with amphibians, plants, and insects. We are losing diversity to the toughest creatures who are multiplying like crazy worms and dominating huge new territories with no predators to slow them down. The ones that win are the ones that are most difficult for humans to control or spread the fastest. Call me chicken little, but this phenomenon is also making farming and forestry very unpredictable (read unprofitable). Margaret makes it clear that she is on a journey of discovery, and I am sure she will hunt down the closest thing to the truth we have.
      The invasive problem results in more chemicals and pesticides, folks…no one puts that stuff on crops for fun. The amount of time that the elegant and beautiful ecologies we have took to come to be is obviously beyond many people’s ability to imagine, so it is easy to simply reject the science…for unfounded belief instead. They dismiss science out of hand, and I say let them prove their claims before tearing down the work of many lifetimes in the field. Human-centric groups (such as many permaculturalists) actively encourage the spreading of invasive plants and animals as long as they appear to benefit people in the short term…it is an “I should have the right to plant whatever I want” mentality, and they might as well be holding a green assault rifle. They also make another fallacious argument that throwing as many species as possible together in a place somehow enhances diversity, and that all soil should be tilled by earthworms so it can be neutral and fertile so we can grow our potatoes. In fact, evolved-in-place plants, occupy many different soil types, and evolve “lock-in-key” with insects and birds and other creatures that need them to survive. If the plant goes, the animals that need it go…if the animal that pollinated it or spread its seed goes, the plant goes. So if we make the native soil of those organisms non-native, where are the natives supposed to grow? We ultimately lose diversity of many microhabitats. This is truly a dark moment in our development when we are unraveling an amazing world of creatures more co-dependent and intricate than we had ever thought before, and the self-serving choose to reject the findings, and push to make things worse. The number of problem invasive species is already phenomenal and mind blowing. So please examine the body of evidence. A great place to start would be the International Union for the Conservation of Nature (IUCN) which represents the work of thousands of scientists all over the world. We are in trouble. Gardeners are gardeners because we love the outdoors and are still connected to the land, although that connection has been heavily exploited by those who want you to believe that plants come from a nursery every year, and soil comes from a plastic bag, and a garden only looks nice with red dyed mulch on it…I think gardeners have the potential to see what is going on and be a force for helping us to learn to live and garden in ways that are more harmonious with the natural world. It is not the easy or convenient path, but large numbers of us need to get busy before it is too late.

      1. Martha says:

        There are 2 species of Amynthys (A. agrestis and A. tokioensis) and one of Metaphire (M. hilgendorfi) that seem to travel together. These worms came from Japan probably in the 1940s on imported plants, were first noticed on the East Coast, and took a long while to really take off in the U.S.. In Japan, they are native to grasslands.

  11. Kathy says:

    Native box turtles are the most ecological worm eaters I’ve ever seen. They scratch and search through leaf litter at the surface and dearly love worms. Box turtles are like mini bulldozers. I bet they could be an answer if they were more protected in their native habitat. But they would need to be reintroduced to areas and protected from raccoons, dogs, and cars. They protect my garden from snails, crickets, and all sorts of vermin.

    I bet those worms came in orchid bedding. Those Asian invasive flatworms which kill our native worms came here to Texas by orchids and the Cuban anoles came from Florida potted plants. The anole eggs are laid in orchid bedding and potted plants. Those invasive anoles kill our native anoles.

  12. Ginger Smith says:

    Ever since I moved into my current house, about 20 years ago, I wondered if it was possible to have too many earthworms. Whenever I asked people that question, they looked at like I was crazy. Throughout my garden beds are piles of worm castings and the soil was always dry and loose. My plants grow but do not thrive, and some areas in my flower beds, plants just do not grow at all. Also, when I would dig in the soil these worms scared the heck out of me with the crazy thrashing about. As of a couple of years ago I learned about the Asian jumping worm and concluded my little wooded acre in Northern Westchester is infested with them. At least I know I am not crazy, but I am sorry to learn my garden is littered with this invasive species. I would love to learn more about controlling them as they are out of control.

  13. Marian Whitcomb says:

    The link to the podcast is for Aroids? Love those, but came for those CRAZY worms! Congrats on 10 years, Margaret…one word…SUPERLATIVE!

    1. margaret says:

      Thank you Marian for the alert. In making a technical correction this afternoon the file got switched, so I’m glad you mentioned. Fixed now.

  14. Cairn says:

    The podcast certainly informed me of an issue I was uaware of. And it provided a forum for gardners around the country to offer ideas on what might be done to control these Asian garden invadors. Good job, Margaret! Keep up the good work you and the experts you interview on your podcast are doing. Off I go to grab a rake and see what may be going on in my yard….

  15. Kathy Olson says:

    I left some of these worm in a bowl and they were gone by morning. Either a Raccoon, possum or skunk ate them. So I hope some of the wildlife can use them to control them. They are just terrible. I wonder if robins would eat them?

  16. Leon says:

    Is this worm the same as the “Alabama Jumper”? After this broadcast, I did a Google search on “Asian jumping worms” and got quite a few hits on the Alabama jumper worm. Apparently this worm is being highly promoted for composting! If this is indeed the same worm, their invasion will be quickly spreading due to these promotional ads on Google and Youtube.

    1. margaret says:

      Hi, Leon. As I understand it, it is a Chinese cousin of the two species of Amynthas that are currently being studied at Wisconsin and elsewhere (Amynthas agrestis and A. tokioensis). The Alabama (or Georgia) jumper is Amynthas gracilis, I believe. It has been used in vermicomposting. I do not know about how much destruction it has achieved in the areas where it is popular for that purpose, but you are correct: many experts are concerned about the potential for issues to occur as a result of vermicomposting so this is a whole other area of discussion./investigation. For years the nonprofit Great Lakes Worm Watch has warned about this. Read what they say.

  17. June says:

    I was checking out videos on YouTube and there are some for Alabama Jumping worms that can be bought online. Are they the same as these Asian ones or are there more than one type of Jumping Worm? Thanks!

  18. Alice says:

    I wonder what Japan and Korea are doing to control the Jumping Worms in their native countries. Their agriculture continues so they must have some successful methods of control.

  19. KC says:

    I live in western MA and listened this podcast in March with great interest, taking some comfort in feeling less alone with THE worst garden pest yet. And that this soil destroying worm affects the woodland ecosystem beyond my yard is even scarier.

    I identified the worms in my garden last fall and I had a horrifying ‘aha’ moment after having scratched my head over the dry, coffee ground appearance of the edges of beds by late summer. I researched the heck out of it during the winter while also making spring gardening plans; I still felt hopeful or was maybe in denial somehow. Now that spring is here, I am finding the hatchlings in all of my garden beds and it’s depressing. I know they can’t be identified until they reach maturity, but they are right near the surface on a dry day, wriggling around and dropping their tails. My soil is depleted and I shouldn’t add compost/mulch as usual because it will feed the worms. All of this to say, I feel ready to quit. (The ticks, deer, voles, etc are hard enough to manage.)

    Margaret, I’m not quite clear, but it sounds like you have these worms, too. I know we are in the early stages of research, but it would be so helpful to know just how my ‘Garden Guru’ is moving forward this spring, during a time normally so full of hope and joy in tending and planting healthy, organic gardens. This is your livelihood! So, you must have a plan, even if it’s experimental. Will you please share?

    1. margaret says:

      What you have written is exactly how I feel, sad to say. I cannot tell yet this early season whether they are in other areas here or just the spot where I first saw them last year in exactly the same way as you describe — the coffee grounds at the edges of beds. The organic fertilizer from tea seed meal that is being tested by researchers (and used by some commercial places I am aware of) is not sold for retail use yet, so I am investigating if/how it or a similar formula can be purchased. I have reached out to the manufacturer and to some estates and public gardens I know who are using it to see if they have any insight. Hope to have more info soon, but again: I’m not sure it’s for retail sale anywhere yet, and it’s not a cure but one direction for reducing them somewhat that is being explored both to see how well it works and also what other impacts it might have (especially if any are negative). Wish I had better news.

  20. KC says:

    Thanks so much, Margaret. In the mean time, are you adding that beautiful layer of compost/mulch as usual?

    You may know, Charles Darwin wrote about worm grunting: mimicking the sound and vibrations of a predatory mole to flush out earthworms. Lots of mole activity here and maybe I should be thanking them.

    I hope your problem doesn’t spread like mine, but I guess that’s exactly what they do so well, like any invasive species. I appreciate your support and knowing we’re in this together. We will just have to carry on!

  21. Caroline Metzler says:

    Hi Margaret,

    I recently ordered some worms for my garden not realizing how invasive they are (Alabama Jumpers). I hadn’t released them yet, but the other night a few (about 10) escaped from their container. I’m trying to figure out how to keep them from spreading from the escape area, which is a small cement porch surrounded by about 20 ft. diameter sandy soil with very sparse dry bermuda grass (hardly anything there to eat, and no cover for them). Two sides of the porch abut the house foundation/crawl space where there is nothing for them to eat. I’ve read everything I can on how to control them, and I poured mustard mixture with meat tenderizer in it over about 5-6 feet out from the porch. Then I poured straight vinegar over the same area. Stinks like potato salad, but not in a good way!

    Can you verify for me how fast they travel and/or suggest anything else I might do to keep them from surviving and reproducing? I tried calling Brad Herrick but he isn’t in his office. I would love to know more about the tea tree fertilizer and how I might obtain some.

    Thank you for any suggestions you might have!

    Silver City, New Mexico

  22. Michael A DuFer says:

    Thanks for the uniquely uninformative interview with the Arboretum guy! You mever got to the point that the link said you could provide the answer, for Gardeners: How do we get RID of the Asian.Red wriggler?

    1. Michael A. Du Fer says:

      I think I may just have to drive them to the surface–or kill them, whilst trying—with electricity!
      I’ll let you know how that goes!
      Wish me luck. (Fried worms, anyone? Perhaps an Eastern delicacy?)

  23. Suzanne says:

    Martha, I am so grateful that I read this article right before going to a garden club plant sale. When I was repotting some of my purchases, I noticed some of the worms were big and crazy, very lively, and seemed to fit the description. Because of your article, I knew I did not want them in my garden, so I put the new plants and dirt, (Unfortunately some already mixed with more soil, so that had to go, too) into a big blue rubbermaid tub.

    I sealed the tub with duct tape, and left it over the winter. I did notice when I peeked at it this spring that the dirt was, in fact, covered with “coffee grounds.” My question is, if the cocoons and eggs can last for a few years, what do I do with this dirt: should I toss the whole tub, sealed, into the trash for the sanitation workers to take?

    I am a little paranoid about dumping just the dirt into a garbage bag: how big are the smallest eggs? And what is recommended to do with contaminated soil?

    Thank you very much,

    1. Martha says:

      Hi Suzanne,
      I just saw your question. You may have disposed of the soil already; I hope they did not escape into your garden. I have tried “solarizing” the soil in black plastic contractor’s waste bags, flattening them to about a inch thick, leaving the bags in the sun in a metal wheelbarrow so it gets really hot, and turning it a few times. Recent research indicates that heat kills the eggs, so after one winter (freezing kills live worms) and solarizing the soil, it should be safe to use. You could put it in pots kept separate from your garden, watch the soil to see if the castings appear. This is obviously not a solution for getting rid of them already in a garden as it is very labor intensive. I am making a lot of compost and adding it to my garden beds, and have sometimes purchased new topsoil, but the worms do like it and eat it pretty quickly (within months). So it’s either build raised beds with some kind of barrier to the existing soil, or keep adding mulch and topsoil, which I am doing.

  24. pat says:

    Use of chickens and ducks seem good. I think I’d encourage habitat for frogs, salamanders, opossums and other insect consumers. Put up stakes at various heights to encourage birds to visit. Put soil in 4 x 4 foot heaping compost in the hot sun, keep moist not wet. Heat can exceed 90 degrees in middle. See if that helps. Maybe we can add parasitic nematodes? Other insects that prey on active prey.

    1. margaret says:

      Research with heating soil is an area that is being/will be explored. I have not read about any nematodes being identified as specifically targeted to these worms. Sadly it is early days and we do not have a solution that is viable on large areas and confirmed as safe for other soil-dwelling organisms and other animals.

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