The season for jumping worms has arrived; gardeners on alert

Research scientists continue to sound the alarm about jumping worms, an invasive species of earthworms that arrived more than 10 years ago. At this time of year, gardeners are an important line of defense.

Jumping worms live in the top several inches of soil and cause severe erosion.

“They can really turn up that top layer,” said Ryan Hueffmeier, professor at the University of Minnesota, and program director of the Boulder Lake Environmental Learning Center.  “They can turn that top layer of soil into something like coffee grounds. And what happens is, you get a big rain, all that soil gets washed out.”

Hueffmeier strongly recommends that gardeners do their homework to avoid bringing jumping worms home. They should check with gardening supply stores to find out where they source mulch. In addition to looking over mulch brought home from the store, gardeners should inspect plants over a week before putting them in the ground.

Hueffmeier recommends gardeners inspect their mulch pile especially if it appears to have a loose consistency like that of coffee grounds or cat litter, which could mean jumping worms have eaten through it.

In spring, the worms are just emerging from their cocoons. Juvenile jumping worms can be difficult to tell apart from other earthworms.

“They're really small worms that are really hard to identify at this time of year. And they kind of look like the European earthworms that we have grown up with and they're, they're a little tougher to identify,” Hueffmeier.

By mid-summer the invasive worms mature, and become easier to identify. A light colored-band nearer the head of the mature jumping worm distinguishes it from European earthworms. Those smooth, light-colored bands go all away around on a jumping worm. Those interested in making a positive ID, will notice that the smooth band is noticeably closer on the front of a jumping worm.

They’re also hairy. Hueffmeier said you may have to get up close with a magnifying glass or snap a close-up photo to see the hair on the segments of its body. A jumping worm has a full bristle all the way around that light-colored segment, as opposed to a European earthworm which has only a few.

Finally, jumping worms live up to their name. “They’re strong. They can actually jump or look like they are jumping around,” Hueffmeier said. “That movement is something that will catch people's eye.”

They also have a tail that separates from their bodies when caught.

The best way to dispose of them? Seal them in a plastic bag, and throw them in the trash. That goes for fishermen too, Anglers should make sure not to use jumping worms when going fishing. Turns out, they don’t make good bait.

Everyone can help researchers and scientists with mapping where the species has been found across the state. If you think you’ve found jumping worms, the Minnesota DNR asks you to take high resolution photos, showing the ring around the worm’s body in relation to its head, and report them using www.eddmaps.org, or contact the DNR at (888)-646-6367 or info.dnr@state.mn.us.