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 have a serious invasion of these earthworms. My residence is in eastern Pennsylvania.
Over the past 8 weeks I have picked up ten’s of thousands of them.
Every morning I fill a 5 gallon bucket 5 inches of the bucket, totally disgusting.
They love to die in my pool, also disgusting.
When using a string trimmer, they come out of the graound, crawl over your feet, like something out of a horror movie.
Sevin seems to kill they, but their is no end in sight.
Any recommendations are appreciated.
Thank you,
Joe
We are having the same problem in Pittsburgh, PA
I live in upper Bucks county in Pennsylvania. I have these Jumping worms in my manure pile and now spreading to my veggie gardens. For some reason, this year most of my vegetables, are doing poorly and the rest are dead.
Is this still being checked on by anybody ? I have the worms.
Hi Emily, It’s best to contact your state wildlife agency to report sightings of jumping worms. Thank you!
Very interesting. This is the first time I hear of jumping worms! The article says that the worms rob the trees of nutrients by eating the organic matter on the forest floor. However after the death of the worms the minerals are made available to trees.
Hi Andre, Thank you for the comment. This article from UW Madison goes into more detail about why the nutrients don’t make it to plants in the same way when jumping worms are involved: https://news.wisc.edu/voracious-asian-jumping-worms-strip-forest-floor-and-flood-soil-with-nutrients/
I have also found jumping worms in my backyard and would love advice on how to manage them. I can’t get the link to the article mentioned earlier to work. Thanks.
Hi Barb, Advice is usually state dependent, so I recommend either contacting the state wildlife department or a university extension in your area to find out what they recommend. Thank you!
I live in Cedarburg, Wisconsin and I have jumping worms, lots of them. I have very nice landscaping and have improved the soil regularly with compost, milorganite and other stuff. When I started seeing these worms, I was happy to have so many worms. Now, not so much. What can I do to stop this invasion? I have been gathering them and killing them, hundreds of them.. Help!!!
Hi Patricia, In Wisconsin, “Watch for jumping worms and signs of their presence. If you find them, report them to the DNR by email at invasive.species@wi.gov.” http://dnr.wi.gov/wnrmag/2015/06/worms.htm Thank you!
Just heard a news report that jumping worms were found in the county in which I live in central Wisconsin. There was little information given there but I then found this page. Good information but it needs to be made more public. When our forests are gone they will take more than our lifetime to replace, if possible. I am surprised at the sarcasm and childishness of many of the comments here. One person brought up an idea that I wondered about too; how about burning? Then again, I doubt many people could be trusted to do this in a safe manner, as demonstrated by their responses below. I have been in a battle all summer with Japanese beetles and feel I am losing this important fight, since they will soon dig down into the soil to overwinter. The weather has been cold and in my city, dry as a bone. In early summer we had a terrible storm that destroyed a large number of mature trees throughout the city. The news about jumping worms feels like piling on. I will be waiting to hear of a solution that I can try in my little piece of heaven. It will take a large effort by many people to make a difference. So far there has been no urgency or concern among my neighbors where Japanese beetles are concerned.
I think I have a problem in my garden with these worms. I live in NY 50 miles north of Manhattan on a deciduous wooded slopped acre. Ever since I moved into my house, and observed the massive amount of worm castings around my flower beds, it appeared that there was too much worm castings and not enough to hold the soil together. My soil is also dry with shade. How to I identify the worms to know if I have the Asian jumping worm? Thank you.
Hi Ginger, I recommend using this form to contact iMapinvasives in NY: https://login.imapinvasives.org/nyimi/report_invasives/
They will know what the best next steps are for your state. Thank you!
Very interesting. I first heard about this worm in a newspaper article earlier this spring. Now I know that the worm I found while digging in .y stones to plant a bush was indeed a red jumping worm.
I see that these things are for sale in the United States for composting!https://texasredworms.com/2013/10/18/jumper-starter-farm/#comments
http://wormfarmfacts.com/Alabama-Jumper.html
Why is that? Or are these a different type? I would think that if these things are such a threat, shutting down operations that sell these things domestically should be a priority.
Hi Jane, The red worms are definitely different and the EPA is recommending them for composting: https://www.epa.gov/recycle/how-create-and-maintain-indoor-worm-composting-bin Because of the overlap in common names, I’m not sure about the Alabama Jumper, however, from the description in the link you share, it sounds like they “dig deep”, which is a different behavior than the invasive Asian Jumping Worm that primarily stays near the surface. Thank you!
To learn more about modern worms, read Thomas Barrett & Earl Shields. There are two kinds of vermicomposting worms which come under various brand names, but are all one of these two types: First, the red wiggler/red hybrid/redworm, & host of other commercial brand names are all descendants of Thomas Barrett’s hybrid, & live in manure heaps & compost piles pretty much always within the top four inches. Second, the African nightcrawler, which was bred from large Florida manure worms that look like nightcrawlers, but act like red wigglers, in terms of staying in the top four inches. What these Asian jumping worms are & what precisely is the problem with them is a mystery I seek the answer to & would be grateful for.
Finding this worm in your yard and reporting it is a first step. No one has made any suggestions about how to manage your yard after a positive identification. I am facing this. I would like to know what recommendations there are for pasturizing compost since this will be the vector for spread in my vegetable garden.
Hi Betsy, Thank you for the question! It seems that best management practices are still being developed. This article by a master gardener has the best advice that I can find online about how to manage your yard after an invasion: http://wimastergardener.org/2016/08/24/experts-tip-new-invasive-species-jumping-worms/ You might also ask your state DNR or wildlife program for further advice on containing the problem and getting rid of the worms.
sounds cool but scary at the same time
These are being sold on the internet as good vermicomposting worms. What is the difference in a Red Wiggler, African Nightcrawler, or the Alabama Jumper? Can we still use the Red Wigglers for vermicomposting?
Thank you! That is a good question – the EPA is recommending red wigglers: https://www.epa.gov/recycle/how-create-and-maintain-indoor-worm-composting-bin
Just wondering if there is a plotted map where these things are, and if there are any efforts to control them. I am beginning to realize that “closed systems” with as little input from the outside is the way to go…I still buy plants but not until I am now doing more with seeds. And when I bring a potted plant home, it is only AFTER I have researched its potential invasiveness in my area and three others with the same climate conditions. I remove the dirt before planting the plant, rinse it off in a gravel area, and solarize it (dry as a bone too).
Hi Marian, Thank you for all of your comments & for this question! We don’t know of a comprehensive map of where they are. In the Great Lakes region, there is a citizen science project you might be interested in that is working on tracking them: https://scistarter.com/project/333-Great-Lakes-Worm-Watch?tab=participate&utm_source=Discover&utm_medium=blog&utm_content=GreatLakesWormWatch