Disturb a jumping worm and it’s like a nightcrawler on steroids: It violently writhes on the forest floor, recalling a snake in a bad horror movie. Try to catch it, a piece of its tail will detach in your hand — still wriggling as you hold it.
But put aside the creepy factor: jumping worms may be the next big threat to northern forests.
Jumping worms, consisting of various non-native species from multiple genera, have become established in a number of eastern and southeastern states. In 2013, species from the genus Amynthas were confirmed for the first time in the Upper Midwest, at the University of Wisconsin-Madison Arboretum.
In the forests and prairies of the Upper Midwest, the jumping worm could significantly alter habitats and decrease biodiversity. Why are they so damaging? And is there anything we can do to stop them?
Why Much of What You Know About Earthworms is Wrong
You probably learned about the wonders of earthworms at an early age. They aerate the soil. They help your garden grow. And they catch fish. The humble earthworm is a creature to celebrate.
Overlooked in all this earthworm love is an important fact: in a significant portion of the North American continent, no native earthworms have existed since before the Ice Age. As such, forests and other habitats have evolved without them.
But people love earthworms. They indeed use them by the millions for fishing, and for composting, and to help gardens grow. And so the worms have been spread far and wide. Even areas with native earthworms have largely been taken over by non-native varieties. The common nightcrawler — familiar to anyone who has ever cast a bobber and hook — is a European species.
Earthworms have also spread into the northern habitats where worms have been absent for thousands of years. The hype is true: earthworms cycle through a lot of refuse, and fundamentally change the soil. This may be good in your backyard garden plot, but it’s not in the northern forest.
“Earthworms change the environment to suit their needs,” says Brad Herrick, ecologist and research program program manager at the University of Wisconsin-Madison Arboretum. “When they are introduced, they make a host of physical, chemical and biological changes to the soil environment.”
Essentially, worms turn the forest floor — a complex community of plants, invertebrates and microbes – into a completely different habitat.
The jumping worm, if established in the Upper Midwest, brings new threats. “We think the changes to native habitats will be similar to other earthworms but even more dynamic,” says Herrick.
Spread of the Jumping Worm
You probably think of earthworms as living underground. But the jumping worm actually lives in the topmost layer of the forest floor — amongst the fallen leaves and other material that cover the soil. It eats that fallen organic material. And that’s the problem.
That leaf litter provides essential nutrients to the forest. Trees need long-lasting sources of nutrients. When jumping worms quickly turn leaves into very loose soil (resembling coffee grounds), they deprive trees of essential nutrients.
They thus can inhibit the establishment of tree seedlings. The altered soil is inhospitable to many native plant species. And that soil also disrupts the relationships between fungi and trees.
In short, the jumping worm could have profound effects on the overall forest ecosystem.
As with so many invasive species, they’re adaptable and difficult to stop. They’re parthenogenetic: they can reproduce without fertilization. The introduction of a single individual is enough to launch a jumping worm invasion.
The worms have an annual life cycle. They die in the fall, but leave tiny cocoons that spend the winter in the soil.
And they can be spread readily by human habits. Take their preferred habitat of fallen leaves. At this time of year, many people are raking leaves into a pile and setting them by the road to be picked up or converted into mulch. The worms — or their cocoons — are thus transported to new habitats. Compost and potted plants can also move the worms around.
“Unfortunately at this time, there are no good control measures,” says Herrick. “The important thing now is to the stop the spread. Everyone can help.”
Stop the Jumping Worm
Herrick and other conservationists agree that prevention is the most effective tactic. If you live in the Upper Midwest, and see a writhing, snake-like earthworm in your backyard, report it to your state natural resources department. (In Wisconsin, you can email invasive.species@wi.gov to report sightings).
The Wisconsin Department of Natural Resources also has a handy identification card to help you distinguish the jumping worm from the common nightcrawler.
Wisconsin DNR also suggests examining potted plants and gardening and landscaping materials for the presence of jumping worms. If you are doing landscaping and gardening work, be sure to clean your equipment and clothing to prevent transporting cocoons.
And if you buy compost, only buy from sources that heat the compost at appropriate temperatures and duration to kill pathogens.
The jumping worm is not yet established in much of the northern United States. The time is now to keep it from becoming the next invasive species horror story.
I just read an article on this species of worm in the Chicago Tribune today. So I googled it. Here is my story.I was doing some landscaping in Lake Geneva Wisconsin at my summer home last weekend.I love to fish.So I was saving the worms that I dug up , but they were different. They were extremely wiggly and hard to put in a container. They were firmer than a regular worm and fatter. The bigger ones would break off when handled. And they seemed to be dying in the container the next day. The fish still like them but I through them out after a day or two. It made me wonder about these worms. But after reading this article , I think maybe this is that invasive species of worm. Am I right? Laura Knop
What if a pet is intrigued by their movement and eats one?
I have recently discovered I have jumping worms – bad!!! Have been trying to find a way we
can irraticate them.. Have heard that Early Bird fertilizer, used on golf courses, does work.
Also, using Bio Char helps the soil. Are you familiar with these?
Am trying to call LowerChippewaInvasives Partnership, Kathy Stahl, who seems to find
ways to get rid of them 90%. Will call her today. Would like to hear what you know about
them!!! Thank You.
I have had these in my Washington Co, MD woods for the last three years. They come to the surface when I pull weeds, and I stomp them, but as has been suggested, you have to make sure the whole body has stopped wiggling.
My house is surrounded by woods where they’ve lived for a while and they migrate from the woods to my backyard. I’ve had them for at least five years and they’ve changed the way I garden. Since they live near the top of the soil they’re attracted to mulch, so I no longer use straw mulch. They destroy the soil and in some places it’s crumbly down 6-8 inches, though mostly the crumbly soil is just closer to the top, 2-3 inches. Where it’s really gotten bad, nothing can grow, at least not from seed. I suppose if you planted something with deep roots it could make it. There seems to be very little interest in or knowledge of this by the landscaping professionals, and very little research money available. A lot of the research that I’m aware of comes out of the University of Vermont but we need major funding for this problem.
I have recently noticed new patches of brown grass in my lawn that can be scraped up or picked up like a piece of pizza, because the patch is dry and has very shallow (if none at all) roots. I have tired to examine the patches before and after I pick the dead patch up; tiny holes appear on top of the patch and underneath, long slender worms quickly dart into the soil before I can really look at them. I usually see only the end disappearing into the soil. The soil under the patch is dry and has no trace of the grass roots. I am very concerned so have been reading online this week. I had only a few patches a week ago. Today, I have many. I could easily scrape up the dry brown patches and find a square foot of bare soil in every square yard of lawn. All information says these worms are bad……….but don’t really tell me what to do other than try to kill them with rubbing alcohol……..or refrain from using composted soil…..or, or.
What should I do for my lawn is the real question. The internet has article after article from several institutions but all only discriptive…………..no problem solving. Please direct me to other interested lawn owners who struggle with this problem and want to help solve it!
Early this spring I planted a large plot of grass in my yard which came in thick and plush. As the summer came on it began to thin and I noticed little piles of the granulated soil described in the article. Had no idea what was happening until I read the article and remembered seeing those exact worms. I live in NE Pennsylvania and they are here! I could not see anything written to control them. Help!
Living in NH I have a huge amount of jumping Asian worms, how can I get rid of them before they do more damage ?
I fear it is too late. They are well established in NY State now and are spreading rapidly. I suspect ours came in on potted plants and potting soil. The only remedy proposed so far is pretty much scorched earth and kills good worms as well as bad.
Time to figure out how to get along with them like we have with the rest of the invasives.
Found them in Omaha , in my friends yard(is this new information)they sure are wigglers, hopefully a weather cycle or some other physical change the landscape will stop them as was with the outbreaks back in the 30 of locust/cicadas.
If you have jumping worms will you still have good night crawlers or do the jumping worms destroy the good worms. I have been finding a lot of worms in my compost and in my garden areas. I find it is extremely difficult to tell but based on what I see, I fear I might have them. I find them up at the surface when digging and find some really large ones. It seems like many worms I find don’t really even have the distinguishing band. The bands I am seeing seem to be close to the front and usually whitish in color and the band in flat and not raised. I have noticed they seem to break very easily even when not pulling them out of the ground. They squirm and wiggle a lot when first detected but then lay quietly if left along. If indeed I have jumping worms, I have not done anything with my soil in an area where I think they might be. I had twice shredded pine bark put down 6-7 years ago. However, were they even in the area back then. I certainly did not see any worms in the compost as I was hand spreading 9 cubic yards. I have taken some photos but do not know where to send the information. I live in Illinois. If I do have these worms, will I ever be able to get rid of them? Lots of questions. Thank you.
It sounds like you have them. The are exactly like what I have. I’m in Illinois.
There was a lot written about the consistency of the dirt made/occupied by the jumping in otms, but are their castings not as nutritious for plants as, say, the castings of Red Wiggler worms?
Post more pictures and show other species so it’s easier to differentiate them from other worms.
Hi! I am Kora. I am in 6th grade. I want to know more about these creatures for my conservation speech. Could you possibly get a list to me of some useful facts for my speech?
Thank you!!
Kora Zebro
Hi Kora,
Thanks for your interest. I believe this blog post should contain all the info you need to make a list of cool facts.
Best,
Matt
Has anyone reported these Jumping worms in Texas? I live in the Keller/North Richland Hills area.
I was doing a test October 7, 2018 to determine if I had sod webworms killing our grass.
The test was 2 T Dawn to 2 gallons water, pour over an area to see if the worms would surface.
They did surface, but do not look like the sod webworms on the internet.
These wiggled and moved around very quickly. There were many of them. One is 6″ long.
Upon capturing one, I looked online, and found info about an Asian Jumping worm found in Wisconsin and the Maine areas in 2013-2014. The “band” around this worm is not in the middle, but closer to the head.