SO-CALLED CRAZY WORMS or Asian jumping worms, several invasive earthworm species that are spreading alarmingly in many areas and degrading soil and natural habitats, are probably the most common pest question I get from readers and listeners in recent years. Many of you have asked specifically, “How can I stop them?”
To find out what scientists know so far, I called researcher Brad Herrick of University of Wisconsin-Madison, who gave us a 101 last year on these destructive worms, and has since published some new insights–specifically about 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.
Brad is Arboretum Ecologist and Research Program Manager at the University of Wisconsin-Madison Arboretum, where the staff first noticed the destructive effects of Asian jumping worms in 2013. He’s been studying them ever since.
Learn how to diagnose the presence of Asian jumping worms; what corrective tactics you can try to reduce the population if your infestation if limited to a small area of a garden; and what directions are next in research about these serious soil-wasting pests in hopes of finding larger-scale controls.
Read along as you listen to the August 12, 2019 edition of my public-radio show and podcast using the player below. You can subscribe to all future editions on iTunes or Spotify or Stitcher (and browse my archive of podcasts here).
invasive ‘crazy worms,’ with brad herrick
Margaret Roach: Welcome back to the show, Brad. I wish we had a more optimistic topic to discuss.
Brad Herrick: Yes, I know. Well thank you for having me anyway.
Margaret: We can talk about plants someday. Right? Cause I know you-
Brad: Yes, that’d be great.
Margaret: I like plants and you like plants.
Brad: That’s right.
Margaret: I don’t like Asian jumping worms, Brad. Oh my goodness.
Brad: Yes, I know it’s one of those things that is another invasive species, but from the research end of it actually it’s very interesting to study and try and get some information out to folks.
Margaret: Yes. So in case people don’t know the basic issue with these worms, because you know a lot of gardeners as we talked about last time we spoke think, “Oh, earthworms are good, blah blah blah.” Can you explain why these species are so worrisome? And they’re not something that’s new, it’s just something that’s reached sort of a tipping point, I guess, where we know more about them now.
Brad: Yes. Exactly, yes, yes. So definitely in terms of the gardening community, we’ve been told for a long time that earthworms are actually a really beneficial component of the soil environment, right? They create—through their burrowing, their feeding behavior, they’re creating castings—they produce a lot of nutrient and they work with nutrients throughout the soil column, they mix soil. And they provide … their burrow provide areas for air to reach the roots, and water to reach the roots of plants. So generally they have been thought of as doing a kind of beneficial ecosystem service, if you will, for our vegetables and our garden plants.
And that’s still the case, except that now we have kind of a new twist on it where we have these newer invasive earthworms from parts of Asia that don’t behave quite the same way as the earthworms that we’re used to.
And what I like to tell folks is that even earthworms that are in your garden, if you live in glaciated areas of like New England area or upper Midwest, where I’m from, there are really no native earthworms.
Brad: Because there are very few. It’s thought that the last glaciation kind of extirpated them, and so our systems aren’t really familiar with earthworms and don’t … especially our high-quality areas don’t need earthworms to function healthily.
Brad: So anyways, so these … even earthworms in your gardens are also non-native, but they do perform a benefit. These new earthworms, they don’t do the same kind of burrowing. They don’t burrow vertically into the soil. They’re not really good at mixing nutrients or mixing soil. They do all their work in the upper few centimeters of soil, or even above the soil within whatever organic layer you might have in your garden. And so, and they turn over, they eat the organic layer, whether it’s leaves or mulch, decomposing wood, they eat it really quickly, especially when they get to high numbers later this summer. And they turn it over so fast that they release all those nutrients really quickly, like a quick-release fertilizer.
And it’s often two things happen. One is they release it so fast and they’re not mixing that nutrients back into the soil. And so it’s often lost through heavy rain events or just not available to the roots, which are lower in the soil. And they’re often doing most of their work later in the summer, when really plant growth isn’t kind of the main thing that plants are doing. They’re thinking more of storing nutrients for the winter if they’re perennials. And so it’s sort of a … there’s a bit of a mismatch in terms of timing as well.
Margaret: Out of sync. Really out of sync.
Margaret: And they kind of reduce the soil to almost like … I don’t know, it’s like a … as you say, they take out all the organic matter. So I’ve read these reports in Great Lake Forest and in the Smokey Mountains and places, natural areas, where they talk about “tree root gingivitis,” where the roots of the trees can’t even get ahold and stay-
Margaret: You know, the soil is being so degraded. [Above, a chart from Wisconsin Department of Natural Resources on the impact on forest soils and ecosystems.]
Brad: Yup. I was going to say in highly degraded areas you’ll see tree roots that are above the soil. You can actually see the roots.
Brad: They’re not actually … because all that organic layer has been removed, so you’re down to mineral soil. It’s problematic.
Margaret: So I’ll link with the transcript of this conversation that we’re having today to our previous one that has more in-depth, sort of the biology and so forth of these worms. But I saw a map on, I think it was like maybe Oregon State University’s website, I’m not sure, that showed what states are affected. And I was curious, it didn’t say what date it was or whatever. I wondered how wide-ranging is the impact of these worms now? And there’s two genera, are they from two different genus of worms, is that what’s going on?
Brad: Yes. There’s I think we have confirmed around 17 species of what are called pheretimoid earthworms, which are these Asian earthworms. And there’s many different genera. We have primarily two, I believe. So Amynthas is kind of the large genus with many species that we have in the U.S., or actually North America. And then there’s one called Metaphire, which as far as I know, we only have one species of Metaphire here in North America.
Brad: And there’s kind of this invasion happening, it’s a co-invasion with three main species. And the three species are Amynthas agrestis, Amynthas tokioensis, and Metaphire hilgendorfi. And that’s getting kind of technical, but they all live in the same area of soil. They’re all functionally kind of the same.
They do the same kind of things in the soil. They’re just different sizes and they can often exist in different abundances. But we’re learning, we’re trying to learn more about if there are differences in terms of how they affect the environment based on their size or feeding behavior.
Margaret: Yes. So in this map that I saw, it had these states colored in a particular color where they are present, and again, I don’t know that … it didn’t have a date and I just couldn’t trace the origin of it, and it seemed like there was the Eastern part of the United States a lot, the Midwest a concentration. And Nebraska I read about, and in Nebraska … it seemed like it was in a lot of different places. So I don’t know how widespread we think it is at this point.
Brad: That’s kind of … yes that’s … what you described there I think is what we know. I mean, definitely the Southeast-
Brad: Up the Eastern Seaboard of states, and now throughout the Midwest into like the central part of the country. I know Oregon has them.
Margaret: I saw it, I saw Oregon as the one [Western] outpost on this, again, undated map, I saw Oregon was, and that’s why Oregon State University had this document, so it’s not just localized to where you are or where I am or whatever. And more and more people are, I think, reporting it. So probably we’ll find out that there’s even more than we know.
Margaret: Yes. So I watched a training webinar the other day with the organization called iMap Invasives, do you know that?
Margaret: And iMap Invasives and we have a … in New York where I am, we have a particular group related to that and it’s like a training online about certain invasive species and one of the ones they were covering was these worms. So I watched, and they gave some sort of layperson tips for ID’ing them, for sort of what do you want to look for? What … now that you’ve been setting them since 2013, if people ask you, other than doing DNA analysis or whatever-
Brad: Yes, right.
(Note: The jumping worm portion of the webinar above begins at about 13:23.)
Margaret: Like what do you say the telltale signs of these worms versus the other earthworms that we talked about?
Brad: Yes, so a couple of things, and it somewhat depends on what time of year you’re looking for them.
Brad: But the first thing that you can see any time of year is this specific soil signature. And that is these Asian earthworms produce a very coffee-like, or coffee ground-like that signature in the soil, really loose, granular soil that’s actually made up of their castings, their excrement [below]. And so they create this layer of really loose soil, really granular soil, which all earthworms produce castings, but most earthworms produce little … kind of little casting hills or little bumps, kind of sporadic around the landscape. Where jumping worms just create kind of a homogenized, uniform look to it. That’s one thing that you can see in the winter, if you get a snow melt, you can … As far as we know that’s a permanent change to the soil. So that’s one thing.
And then as they mature, so in Wisconsin they’re almost … we’re almost seeing mature adults [in July]. So Amynthas, or jumping worms, generally if you look … if you have one and you look towards the head, even if you can’t figure out which end is up, there’s a white ring around one of the ends.
Brad: That goes all the way around the body, and that’s called the clitellum, and that’s where they produce cocoons that are the new offspring. It’s kind of the reproductive center of the earthworm. And all earthworms have one, but most earthworms, their clitellum is kind of the same color as the rest of the body and it’s raised, and it doesn’t go all the way around. If you turn the earthworm over, it’s kind of like a saddle where it doesn’t connect underneath.
Margaret: Right, not a band.
Brad: Not a band, right.
Margaret: Right, right. [Below, from Wisconsin Department of Natural Resources, photo of common nightcrawler, top, and Asian jumping worm beneath it.]
Brad: The jumping worms all have a band and it’s kind of a milky-white band when they’re fully mature adults. That’s a telltale sign. There’s no other earthworm that isn’t a jumping worm that has that kind of structure.
And then lastly, just their behavior. They’re called snake worm or jumping worm for a reason. They can be very erratic, very … They’re not aggressive, they just don’t like being handled, and they will flop around and they’ll wiggle away. They’ll even try and drop part of their tail, the last several segments, to escape being handled roughly, where other earthworms are kind of wiggly, but they’re not actively flopping around and trying to get away from you.
So … and I guess maybe more thing to mention is that early in the spring, April, May, if you’re seeing fully formed earthworms, large earthworms, those won’t be likely, won’t be jumping worms because jumping worms are an annual species, and so under normal climate conditions they’re going to be hatching from cocoons. They’ll be really tiny in the spring, and won’t be full size until the middle of the summer.
Brad: Or end of the summer even. So any large earthworm you’re seeing in April, May is some other species that is not a jumping worm.
Margaret: Yes. On this training, this iMap Invasives training webinar, one of the things that they showed was the movement that you were just talking about, and they had … I don’t know whether it was a night crawler or some other kind of earthworm, and an Asian worm, and they compared. And it’s as if the older earthworms, they kind of move forward like an inchworm, and not exactly, they don’t curl up their backs, but they move forward in a forward-movement direction as opposed to sort of this sidewinding, snakelike wriggling thing, this-
Margaret: Do you know what I mean? I mean, that was very dramatic.
Margaret: As you were saying, so here we are, a lot of us have them, more and more counties each year as I read about them. I’ve been reading about them for a number of years, and again, I’m seeing more places on these maps and more reports from different cooperative extensions, and university researchers, and so forth in more places.
So you are exploring with your colleagues there at Wisconsin-Madison, you’re exploring some directions of “What do we do?” Not expecting an instant answer but, and I saw you recently published a paper about the heat tolerance of the cocoons, the sort of reproductive … the little egg sac-y kind of thing, isn’t it? [Laughter.] The cocoons of these worms; you’re exploring that. I wonder if you could tell us a little bit about what you’ve been doing and what have you learned so far?
Brad: Sure. So we’ve been working closely with our Department of Natural Resources, and they’re obviously very interested in statewide spread, and if there are ways of controlling the spread. And so we’ve gotten some funding from them the last few years to explore that question of: Is there a way to control them? And if so: What’s the most effective way of approaching that question?
And so we think that given that these are annual species, like I mentioned, and they overwinter as cocoons, which are just little 2 millimeter size brown, like you said, kind of sacks that hold the embryo. We think that they’re being spread primarily through people moving cocoons inadvertently.
You can see the earthworms and you can avoid spreading them. The earthworms themselves won’t stick to your shoe or the shovel that you were working in, but it’s going to be the cocoon that gets stuck easily in soil and then can be easily moved, or even during rain events they can move over land. They can just come with the soil if you have erosion. So and they’re so hard … you can’t see them in the soil. They’re so hard to find. So we thought is there a way that we can sort of throw a wrench into that part of their lifecycle, and focus on those cocoons?
And what we looked at with this most recent paper is that many states, including Wisconsin, regulate compost. So large commercial composters have to follow statewide standards that are pretty standard across the U.S. in terms of state policy. But that is that depending on the type of compost pile that has … the pile has to be heated up to 131 degrees Fahrenheit, which is 55 degrees Celsius, for a period of three or 10 days, depending on what type of pile. And that includes mixing it periodically.
And that standard is there to minimize the potential of having harmful bacteria, or fungi, or disease in the compost that may hurt your soil. And so our thought was, well, at that temperature, can these cocoons still remain viable?
We know from previous research that earthworms themselves cannot withstand that kind of temperature. And so we basically … and in the lab collected hundreds of cocoons and subjected them to different temperature regimes from 20 degrees Celsius to 55 degrees Celsius for three or 10 days. We ran that for several months. And then we dissected each cocoon to see if there was an embryo, or an actual worm, or what was happening within the embryonic tissue.
And what we found was that at 40 degrees Celsius, which is a 104 degrees Fahrenheit, anything at that temperature or above contained no viable cocoons. There was not one cocoon that had a viable, from what we could see, a viable embryo or an earthworm. And so that’s … I would say 104 Fahrenheit is much less than 131 degrees Fahrenheit. And so the temperature that’s being reached in these large compost facilities would kill the cocoons.
Now it’s always … with research there’s always a caveat that that’s the temperature … It was a lab experiment. But 131 degrees is 131 degrees, and so if it’s reaching that much in the compost, then we’re pretty sure that if it’s being mixed correctly and all of the compost is getting to that temperature for at least three days, then that should be free of cocoons.
Now what happens after that, that’s where we could get another sort of an avenue for new invasion, if the equipment that they’re using to move the compost to the packaging facility is not clean, that could be a source of contamination or … you know what I mean?
Brad: At other places along that line of producing the compost, that you could always have an accidental introduction. But the temperature itself, it won’t be looked at, and at least from our study, we found that 104 degrees Fahrenheit is enough to kill cocoons. [The abstract of the paper is here; an article on the University website explains it.]
Margaret: So do you feel, or hope, or hope, we all hope [laughter] but do you feel that dot, dot, dot down the road, this exploration of heat tolerance of cocoons, that there may also be some way to apply this to other than a compost setting or what are you thinking about that?
Brad: Yes, that’s the question.
Margaret: Because you have them in the Arboretum. I mean, you have these worms in the Arboretum, right?
Brad: Right. And that’s the question that I’ve been getting a lot, too, is how as a homeowner and gardener, “How can I apply this to my yard?” And that’s sort of the next step. What is … how do we apply this research now to on-the-ground management. And some of it may not be applicable. It all … it’s very, I think, case-specific. So one of the things that we’ve sort of talked about is this idea of solarization of soil.
Margaret: Yes. Yes.
Brad: So if you have a yard or a garden that has the right aspect, it’s not shaded, and you have areas that you can put down a clear plastic over an infested area of soil, it’s possible that that could heat up to a high enough temperature where we think the cocoons are going to be right at the surface of the soil or just below the soil surface. So they should be … you should be able to reach 104 degrees … at that soil level.
Margaret: Yes. For three days, right.
Brad: Yes. That’s definitely one way to do it. And actually there’s been research looking at prairie systems and using prescribed fire, and what they found was that when they put a fire through an area that had cocoons, that the fire didn’t actually impact the earthworms, because the earthworms could actually move below the surface far enough-
Brad: ...where they are buffered. But the cocoons were significantly impacted.
Brad: And so we know that heat can work on the cocoon. And then obviously if you do that enough times you’re going to deplete that cocoon bank. And sort of like a seed bank, right?
Brad: If you deplete the cocoon bank, you’re going to reduce the population over time.
Margaret: Yes. What do you think about … I mean, so here are those of us who have them, we might consider solarizing probably can’t hurt. Some cooperative extension websites I see, they say when you identify the adult worms at this time of year [July] or a little later, put them in a plastic bag and speaking of heat, cook them to death, so to speak by putting them in the sun. But I don’t know, I mean how many are there? There must be 8 billion.
Brad: Right, yes.
Margaret: But are there any other tactics that you think that you think that we should be under … sort of doing at this point?
Brad: Yes. So, and again, like this is a case where the need for information is outpacing the research knowledge. [Laughter.]
Margaret: Definitely, definitely, yes.
Brad: Yes, right. So a lot of it depends on your scale of infestation. If it’s a really small scale, and this is the thing about education, is knowing what to look for and identifying areas that look like they might have the jumping worms.
Brad: If it’s a really small area, you can use just a simple mustard pour. A third of a cup of dry mustard powder with a gallon of water, and pour that over an area that you think might be infected. [Above, graphic from Karen Ceballos, NY Master Naturalist Program Assistant, Cornell Department of Natural Resources.]
Brad: And just literally with the adults, it irritates the adult skin and they will come … their responses to go vertically up the soil and out. And you can pick them out.
Brad: And you can put them in a plastic bag or whatever. Over time, you’ll deplete their ability to produce cocoons.
Brad: Again, it’s not a one-shot deal-
Margaret: Oh no, no, O.K., good.
Brad: …but that’s a small-scale remedy.
Margaret: Good, good, good.
Brad: Yes. And then again, I think it’s … we’re working on, there’s a fertilizer called Early Bird fertilizer-
Margaret: Yes. Yes. And I’ll give the links about that, yes. [Update 12/19: The fertilizer is no longer available, the manufacturer says.]
Brad: Yes, doing some tests on to see what the dosage should be, and getting it out in the literature that it does work, and see if it works on cocoons as well. People are already going ahead and trying it, and I think are seeing some good results, but it can be kind of a messy process because the worms come to the surface and die.
Margaret: Oh, that stinks. [Laughter.]
Brad: And then you have worm guts laying around, which they don’t … the worm body doesn’t last forever so it’s kind of … if you can tolerate that.
Brad: So there’s some kind of chemical applications at a large scale. Frankly at a large-scale infestation we don’t have … that’s where our kind of gap is.
Margaret: In the natural habitats, yes.
Brad: In the natural habitat, right, right, right.
Margaret: Well Brad Herrick, I’m going to keep checking in with you. [Laughter.]
Brad: Great. Happy to talk.
Margaret: Because you’re my 411. Yes. But thank you so much and keep up the good work because I think this is one of the really, really important problems to solve and what you’re doing is shedding a light on some of the possibilities. So thank you.
learn more about asian jumping worms
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(Photos from UW-Madison Arboretum except as noted.)
MY WEEKLY public-radio show, rated a “top-5 garden podcast” by “The Guardian” newspaper in the UK, began its 10th year in March 2019. 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 August 12, 2019 show using the player near the top of this transcript. You can subscribe to all future editions on iTunes/Apple Podcasts or Spotify or Stitcher (and browse my archive of podcasts here).
Appreciate the updates you’ve been sharing on this topic. Can you provide more information about the Early Bird fertilizer you’ve referenced — what makes it different and why it may work on these worms? For those of us with larger gardens or acreage, we’re hopeful for solutions that can scale to fit. Hand-picking isn’t necessarily an efficient option for us. Thanks so much!
It is a low-nitrogen fertilizer made from extracts of the tea plant (which is a camellia), specifically tea seed oil. That contains saponins, basically a toxin that plants produce. Some early studies on it-—many of them were from Kentucky golf courses, to try to eliminate the little hills of castings that regular earthworms left behind that were messy and undesirable on the greens, not research about these Asian worms at all-—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 worm species yet and that’s happening gradually now–looking at using a liquid version or a granular version and coming up with what minimum dosage that you would need to reduce the population or get rid of the population—and also more importantly what are the potential side effects, the impacts to other beneficial soil biota? So it’s not ready for prime time yet it seems, in terms of thorough research with specific guidelines and safety considerations taken into account.
Thanks for that additional information. I see why it needs to be better understood, especially given the potential impact on the overall worm population. I’ll stay tuned.
I live on the WV Va border and have loads of these jumping worms. I may have brought them in on bagged compost that I have used around all my gardens for years. I have so many in spots it is quite creepy! This being said from a person that always loved earthworms.
Hi – do you know of links or maps where I can see where these worms are? We’re in Columbus Ohio and I think we have then
This was eye opening and very helpful
I live in Pike County and I’ve identified these worms. I notice that some plants are not as vigorous this year. While waiting for a solution, how do I increase my soil fertility. Should I be fertilizing more?
Early Bird Fertilizer is labeled as 3-0-1 for NPK. I would hesitate to actually pay money for something that low in value.
Hi, Jill. Organic fertilizer formulations are by nature low N-P-K; so, for example, the basic general-purpose formula by Espoma (a popular and old organic brand) is 5-3-3. Without chemicals, you’re not going to get much higher than that. But this one is very low, you are correct, because it was specifically developed for a particular use in the gold-course industry and made from extracts of the tea plant (which is a camellia), specifically tea seed oil. That contains saponins, basically a toxin that plants produce. Some early studies on it-—many of them were from Kentucky golf courses, to try to eliminate the little hills of castings that regular earthworms left behind that were messy and undesirable on the greens, not research about these Asian worms at all-—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.
So it was never developed to be a big nitrogen boost for general purpose or home garden or agricultural use, and it only is now being looked into by other than golf course managers because of this worm invasion — and whether the way it reduced messy worm castings on the greens might give hints for controlling these invasive worms, too, some day.
There hasn’t been a lot done on the Asian worm species yet and that’s happening gradually now–looking at using a liquid version or a granular version and coming up with what minimum dosage that you would need to reduce the population or get rid of the population—and also more importantly what are the potential side effects, the impacts to other beneficial soil biota? So it’s not ready for prime time yet it seems, in terms of thorough research with specific guidelines and safety considerations taken into account. But yes, not a big source of nutrients and never meant to be for that purpose.
Hi Brad and Margaret,
I live in N. VT and I have jumping worms all throughout my veg garden and yard!! I’ve not noticed any problems with my plantings and shrubs yet but these little devils are popping up whenever I take a shovel full of soil. I’m considering running my chickens through the garden this fall to see if they could help deplete the adult population somewhat. I suppose the birds could snatch up some of the cocoons too. It’s worth a shot.
Thank you for this great information and I’ll definitely tell our VT Natural Resources Dept.
Given the scale of invasive pests we have to deal with at this point, I’m interested in when we will get to the root of how these pests enter our country. If we don’t understand how Asian jumping worms, emerald ash borers, spotted lantern flies, etc. have entered our country and finally fix what allows people to bring these kinds of pests into our country, we will fight a never-ending battle to prevent our local fauna and flora from being destroyed. Can you address this is a future podcast?
Yes! I have seen evidence of arrogant people who aren’t even embarrassed about sending African violets around the world labeled as art supplies! If they are doing it, everybody is doing it and so there is a ton of uninspected stuff coming here all the time. ☹️
Hi Elena (and Lauren). Hi Elena (and Lauren). A lot of them come in on packing/shipping materials, and I have interviewed some scientists trying to figure this out and stop it. For example, read this interview about emerald ash border and other imported forest pests, and also this one about ask and oaks being threatened by such invaders.
I’m wondering how the Asian people have lived in harmony with them for so long. There has to be a balance with them and maybe that counter-balance is still missing and we are just seeing it’s bad side.
Hi, Sheri, and yes: the reason they are “invasive” here and not there is because like all creatures they are part of the ecosystem there for thousands (millions) of years, and there are checks and balances among all the creatures in that system. When just one organism gets exported to a new land, it has no natural predators to keep it in check like back at home. So some such transplanted creatures get quickly out of control. Think: Asian longhorn beetle, hemlock woolly adelgid, spotted lantern fly, emerald borer, you name it.
So WHERE is early bird fertilizer for sale!? Can’t find it for sale, just descriptions online.
Thank you for this podcast; I’m sharing it on FB and emailing it too.
Hi, Lauren. It has up till now been a specialty product for golf course management, from Ocean Organics Corporation — not a consumer-directed product. Now there is interest in testing it and perhaps adapting it after research to this use, against the Asian worms, but it’s in the early stages I think. So it’s not something you will find on the shelf, and again: the protocol, application rate, and also the potential harm if any that it can do to desired soil life are just not fully known yet as I understand it. So though some people are ordering it from the manufacturer I believe and trying it, it’s not sorted out yet and as Brad said in the interview: stay tuned for ore research results.
Over the last few years we started seeing more Japanese Beetles around our yard so we began treating our lawn with fairly good success. I also started noticing more grubs in my flower beds and it finally dawned on me that the reason I couldn’t keep Irish Moss and some other plants alive might be due to grubs. Last year I discovered I have jumping worms most likely introduced from some shrubs I bought with a soil mix that was heavy in compost. I actually saw live jumping worms when I pulled the plants out of their pots. I’m sure there were also cocoons but at that time I didn’t know to look for them. Back to the grubs: I’ve expanded my use of Japanese Beetle grub control products to include a mid spring application and a July application. Also, instead of applying grub products to just the lawn, I now include all my flower and shrub beds as well. This might be hard on the beneficial worms and insects but it also seems to be reducing the number of jumping worms as well as grubs; I’m only rarely finding one now. I read somewhere last year that grub products might kill worms or at least render them sterile. Do you know if there has been any testing done using grub control or other chemicals such as Sevin to help eliminate jumping worms?
Would you please link the map you referred to?
Here it is, David…very small and undated so not super-helpful.
I live in Wisconsin and have had Asian worms for 3 growing seasons. They continue to multiply and spread. This year the wild turkeys and the robins are constantly in my gardens and ripping up the dirt to gobble down these creatures. I have found both the large species and the smaller worm species. While the birds are feasting on the worms I would assume that they are also helping in spreading them to our entire property when they defecate. The soil in some of my gardens is totally of a coffee ground texture. I have thought about using the Early Bird Fertilizer and did contact the UW horticulture department and was told they didn’t recommend it as it contained too much nitrogen and they didn’t have any information on what they would do to shrubs and trees. It would be nice to get some definitive direction on what one can do to lessen this problem
I think it will be awhile longer, sadly, before we have that clarity, Jean, until more research is conducted. Very frustrating, I know.
I’m so glad you’re continuing the jumping worm updates. Hoping for good news before I find any here!
Josef Görres in VT has also been studying these worms. It is possible (although not studied as far as I know) that biochar may work to get rid of them. The VT Master Gardeners have a blog spot with a lot of information as well on the worm and on Dr. Gorres’ studies. One note that they make is that the worms can absorb a lot of heavy metals, so be careful if chickens are eating them. I have found that the Robbins in my yard tend to avoid them. The worms seem to startle them. I have some hopes that garter snakes, who do eat worms, might eat them, but I have not found any information on that.
Hi, Jan. Yes, in the previous interview Brad did mention that some researchers are exploring biochar, correct, in a finely ground form I believe…but like with the tea tree oil fertiliser we don’t know yet how/when/what/if. More research.
Margaret, a couple seasons ago I started to encounter what I thought were really lively earth worms in my garden and perennial beds. I thought that the healthy soil building practices that I have been learning thru Joe were starting to pay dividends with very healthy worms. Now I realize that they are behaving just as described by you and Brad. I live in zip code 15943, Cambria County, Pennsylvania. I work in Allegheny County, Pennsylvania. I have been surprised a few times while climbing dry hillsides to discover groups of lively worms just under the dry leafs. The reason they caught my attention was that usually the native worms are not found on the surface in such dry conditions. Now I realize that I have been seeing jumping worms.
I may give solarizing a try in the garden beds in spring but that is not a good option for the perennial beds.
I heard you mention the jumping worms before Margaret but I did not know how they were different. Thank you Margaret and Brad for this information.
Nanty Glo, Pa
You are welcome, Forrest — and I am sorry to hear they are there, too, as gardens and wilder places. I hope against hope that researchers like Brad and elsewhere continue to piece together clues.
I have found that vinegar (I had only cider at the time) kills the adults and younger worms
very quickly. There will be dozens under a pile of discarded weeds when I remove them
and a dose of vinegar works quickly.
This is interesting. I could pour What we don’t know us if it will kill the cocoons though. I just discovered them this weekend and I’d be willing to try anything since I won’t be able to garden in my raised beds any longer. Upstate NY
I found these worms in the garbage can We use for soul we purchase. It frightened me and it strange to see the worms there. I googled it and dumped the can of soil.
I however am not sure how much soil I used prior to noticing the worms.
I have noticed little piles of dirt here and there in the blue creeper.
Question: is that evidence the worms were there?
The little hills of castings, or middens, such as in a lawn here and there, can be from other worm species. So that would not be a way to definitively tell.
We are hikers. Is there a major risk of distributing the cocoons on our shoe soles?
If yes, is there some way when leaving infested areas or entering new areas to kill the cocoons, for example spraying the soles of the shoes with something like alcohol, vinegar ir diluted bleach?
The Dept. of Natural Resources for Minnesota, for example, recommends caution as it would for preventing spread of any invasive (look on this fact sheet under “What You Should Do” and the subheading for “Recreationists.” So yes, they do recommend cleaning anything that comes into contact with the soil (tools, boots, other gear…) before moving to another location.
I have had these worms for three seasons in my central Illinois vegetable garden and, of course, they have spread elsewhere. I’m fairly certain that they came in on some muddy seed potatoes which were from Minnesota. The mole activity in my vegetable garden has increased exponentially since the worms were introduced . Is it possible that they are eating these tough to kill villains? I hope so…
I tipped out a garbage can which had some wood chips from my last firewood delivery in the spring, just to dry out the wood and tidy up my garden . Then I spotted these beasts! I got my wood ash and sprinkled it on the worms. They didn’t like it. But they obviously were already in the wood. I got the idea from when I came back from vacation and found my dog sitter had put something in my compost heap, which brought maggots. I freaked out, looked up on you tube and saw an australian guy put lime on his. So I did, then used wood ash from last winter.Did the trick. I realise this isn’t going to solve the problem and I am eagerly awaiting more research, New gardener in NE Pennsylvania. Worried.
These worms are on my property. These are also in my compost pile – is that because it is not hot? It is a bit depressing.
Thanks for this. I am dividing perennials and have discovered these creepy things. They kind of surprise me with their size and wriggling. You are my go to woman for diagnosing my garden troubles, but also for inspiration.
I have found that either sodium bicarbonate or table salt will also kill them immediately. I am beginning to try application of the biochar and diatomatious earth. Problem with diatomatious earth is that it must be dry to be effective, I have had them wherever leaves accumulate…trying to keep leaves raked up is difficult with huge trees and close neighbors
I read in the article that you should use clear plastic for solarization. Wouldn’t black plastic get hotter? Also, if the buggers can’t stand heat, why not pile some kindling or such on your beds and set it on fire. Maybe would kill them as you say they live on the surface. Then since they don’t like biochar, there you have biochar (sort of) left behind. Just thinking…..
We had a horrible time with them here in southern Connecticut last summer. Before I knew what they were, I was actually covering them back up after disturbing them! I could kick myself. By the end of the summer, I got smarter and we removed an entire bucket of them from two raised beds.
We will do the mustard pour this spring but what’s the best timing for it? I dont want to do it too early before they have hatched. Also, I am not going to use an organic mulch this year. I’m not about to feed them. Thinking plastic or paper. Any better options?
Timing: They don’t reach adult stage till summertime, like close to July-ish? As for mulch or not…I don’t know what is the better approach, since they are able to just move to the next spot and degrade it by using up all the organic material there, . Another way to look at it is that you do want to provide more organic material so that they don’t truly degrade the soil to mineral only with no organic matter. Again — don’t know really. In my earlier conversation with UWisconsin-Madison’s Brad Herrick, he said they spread in one year about 13 acres at the Arboretum by themselves — so I don’t think you are going to starve them to death.
We live in suburban Chicago and had a terrible infestation of them in most of my gardens and lawn last year. We are starting spring clean-up now and use our chipper to grind leaves, making a coarse mulch to spread in lieu of mulch. Not sure if this is helping or adding to the problem?? HELP…these things are awful!
Hi, Barb. I don’t think anyone knows — no solution at this point. You could look at it this way: if you keep putting down organic material, that eventually works into the soil below, maybe the soil doesn’t get as depleted of all its organic content by the worms’ work? Don’t know.