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.
We have discovered thousands of jumping worms in our flower beds. They were not there, to our knowledge, in the Spring.
We have 1/2 an acre in Greene County NY.
What can we do? We are bagging all that we find and putting them in the garbage.
I live in central PA and thes worms exist in my yard by the thousands.
my soil is mostly like coffee grounds.
I feel the only thing I can do is to make sure I keep adding material to my soil
I remain very concerned
We have a jumping worm infestation here in western Pennsylvania. We removed a quarter bucket in a small area in our garden yesterday. Please let us know if there is any answer to irradiate these disgusting worms.
I live in Alabama and have spent many years creating a Hosta garden, which has well over fifty different varieties. I discovered Alabama Jumping worms, or Asian Jumping worms, or Snake worms while tending to a part of my Hosta garden. There were absolutely no worms in the garden years ago. I realized where they had come from while transplanting a purchase from a local nursery, I found three large Jumping worms in the container. Previously I would have thought it was an added bonus because worms are beneficial, right? Every year I apply new compost around the Hosta’s and last year they were all doing well and in excellent condition. This year they are being eaten alive by the worms. The dirt is crumbled and resembles something you would see in a horror film for gardeners, there is absolutely no compost left, it has all been consumed along with all of the normal dirt. I spent a lot of money buying dry mustard, believe it was eighteen pounds, from Amazon and Ebay. You mix 1/3 cup of mustard with a gallon of water and pour it on the soil and the worms come up out of the ground. I pulled hundreds, and I mean hundreds of these worms out of the garden area. This works great if you can keep buying the dry mustard. I have since resorted to digging worms most every day but I am losing the battle. The only thing left to do is to dig up what is left of the Hosta’s and plant them in containers, of course after the plants and roots will have to be thoroughly washed to remove any eggs. The problem is now I have to come up with over fifty containers that are large enough to hold each Hosta and of course the potting soil to go into each container. These worms are no joke and will devastate what you have put your blood sweat and tears into and no, all worms are not created equal, these Jumping worms are not normal, they eat, reproduce, and eat some more and will wipe out an entire garden in one summer.
I have not contacted the nursery because in reality I am too upset and afraid of what I may say and because it is something I should have known and I should have checked for the worms and/or any other invader before planting it in my garden. Had I not experienced what total devastation these worms can and will do, I would have scrolled by this post, read it and kept on going, not retaining or realizing what is really being said. The bad thing is I can’t find any source of information on anything that can be used to get rid of them other than picking them out by hand every day and in the meantime, I know I am losing because the Hosta’s are looking worse every day.
Signed,
Old lady digging up worms in dead soil while angrily throwing the huge nasty Snake worms into a metal bucket to bake in the sun, every day.
Take this information from Matthew very serious, it could change your life.
My large garden is full of them. I had them last year but killed as many as I could by bagging them and putting in sun. I have MORE this year and they are larger. I mulch my own leaves and others. After reading your article I am wondering if mulching was the wrong thing. Should I just use bought bagged mulch? Again I am bagging as many as I can dig up but they have already killed many of my hostas and I do not know how much more. I have spent years building my garden and I am sick like I am sure others are.
Any ideas would be much appreciated.
I discovered jumping worms in my yard in Jamaica Plain, MA by inspecting the “coffee ground” soil. Every day now I’ve been looking for them, and I can see the damage they do to the plant cover where they are. When I find them I put them in a tub, then cover them with water and a little plant-based dish soap as suggested in a New York Times article. This kills them reliably in several minutes, but there are always more the next day. I don’t know what the solution is.
I’ve noticed these worms in my wood chip piles for years and called them “breakers “ because they just break apart when trying to hook them. Now that I’ve starting worm farming and discovered the bad worm I now will collect and try to eliminate what I can! Any advice? Do they have any other use?
I read this article because I found some jump worms I’m my back yard here I’m Massachusetts. Should I be concern? Should I contact someone?
My grandson discovered TWO worms in our organic, fenced-in garden. That was yesterday. I live in southern CT and I’m very disheartened by these creatures. We live one house away from marshes that lead to Long Island Sound. Yet another plague to battle.
Robert- I also garden in the Hudson Valley( Saugerties ) and last summer while pulling my garlic I saw them. Margaret Roach had just written an article about them in the NY times so I knew what I was up against.
I contacted the Ulster Country extension agency and they referred me to the Green County extension agency. They are part of a study with the University of Vermont on the possible efficacy of using alfalfa pellets to dry them up. The worms’ themselves will die off in the winter but they leave their cocoons which will overwinter. Each worm apparently makes 60 worms!! I pulled a lot last year but feared they had already laid their cocoons..
Needless to say, I have been pulling worms like a cray person ( my once calm, happy place in the garden is now a killing machine!0 We’ve already pulled a 5 gallon bucketful with some assorted dirt mixed in. We put some pellets in the bucket them dump it on a far place in our driveway to solarize them ( a nice way to say…) they do stink for a few days then they decompose.
I had put the pellets on in the fall and then before winter. Can’t say it really helped but the nitrogen at least was good for the garden!
I’m hoping that since we got a very early start on them this year and will keep being vigilant( any free time on the weekends- lets go kill some worms!)that we will prevent a massive cocoon laying event…
good Luck!!