Invasive jumping worms spreading quickly in Wisconsin

MADISON, Wis. — When you’re out in your garden, ecologists want you to look for Amynthas, an earthworm known as jumping worms.

They’re an invasive species that’s spreading quickly around Wisconsin and the U.S. They were first discovered in Wisconsin at the UW-Madison Arboretum in 2013.

“We didn’t think they were here in the state. (It was) just kind of a random observation and it just launched this whole research program and outreach and communication around this new invasive species,” said Brad Herrick.

Herrick said he and experts at the DNR are attempting to slow the spread while trying to understand how the worms are impacting local plants and the environment.

“They’re moving so fast, before the science can kind of catch up (and say) ‘Hey, this is what might happen if they move into your backyard,'” said Herrick.

He said the worms are being spread by people inadvertently, through moving mulch, trading plants or even on boots. This is also probably how the worms arrived in the U.S., being transported in plants from Asia.

“They don’t have any predators in this new habitat,” said Herrick. “They’re able to spread and change the soil structure. They eat a lot of the organic matter that’s really important for plants. They’re removing that quickly from gardens and forests.”

Herrick said jumping worms produce fine soil similar to coffee grounds. If you see that your garden has loose soil or you notice changes in your plants, that could be a result of jumping worms.

The worms flop around and move like a snake, giving them the name jumping worms. Adults will have a white band around their bodies near their head.

To find them, you can pour a mixture of mustard powder and water over the soil.

“What happens is that that mustard is a skin irritant. If there are earthworms, they’ll come right to the surface and you can pick them out,” said Herrick.

Herrick said it’s recommended that you get rid of the worms by putting them in a plastic bag in the sun for a few hours, then throwing them away.

“The earlier that you detect a possible invasion, then you can pick them out because there might not be that many,” he said.

If you have a large infestation in your garden, it’s important to be careful to not spread the worms to other yards. Herrick said you should clean your gardening tools regularly and avoid trading plants with neighbors.

He said in late June and early July the worms fully mature so it’s a good time to look for them.