Jumping Worms In Oregon: Invasive Species Leaps Into Gardens

PORTLAND, OR — If you look down and see a worm, you might not think much about it. Certainly it may not occur to you that you're seeing a member of an invading hoard.

But two invasive species of jumping worm are causing problems in Oregon and at least 33 other states, scientists said.

The worms look like an earthworm or nightcrawler, both of which are beneficial to the soil and environment. But the jumping worm, which is native to Asia and is being seen in more places around the United States, is not.

The jumping worms affect the soil differently, making it less hospitable to growing things, Sam Chan, a watershed health and invasive species specialist at Oregon State University, said in a news release.

The jumping worms earned their name by their near-constant writhing and ability to throw themselves around a foot into the air.

Earthworms burrow deep into the earth and release nutrients as they go. But jumping worms tend to stay near the surface and consume much of the leaf litter and other mulch that are beneficial to soil, according to Chan.

That creates two problems, he said. First, the mulch is important to gardens and forests because it helps preserve the moisture that soil needs to thrive. Second, by eating the leaf litter, the jumping worms create bare spaces where invasive plants can grow.

There's no way to know how many worms there are now across Oregon, Chan said.Two species — Amynthas gracilis and Amynthas agrestis — have been in the area since the 1920s, he added.

Many states have outlawed jumping worms, but they are still easily found online, Chan said.

"Jumping words are probably here to stay," Chan said. "We want to minimize their spread. You don't want them to get established in your garden."

Chan offered advice on how to minimize the spread of the worms.

• Shake off the roots of plants when sharing or buying them.
• Get bare roots when possible.
• Be careful about sharing mulch and soil.
• When buying from nurseries, inspect the soil carefully before you replant.
• Make sure to brush off your shoes and equipment as you move about the garden.

If you find a jumping worm, call the Oregon Invasive Species Council hotline at 866-INVADER (268-9219).