By Allison Finch - May 24, 2022

Gardners beware -- the invasive Amynthas agrestis, also known as the Asian jumping worm, could be wiggling around a garden near you. These worms are known for their insatiable appetite and ability to jump a foot in the air. Yes, you read that right.

"True to their name, they jump and thrash immediately when handled, behaving more like a threatened snake than a worm, sometimes even breaking and shedding their tail when caught," said the California Department of Food and Agriculture (CDFA) in a report, adding that they have been known to jump off the ground or out of bait cans.

As if that's not disconcerting enough, the worms "are extremely active, aggressive, and have voracious appetites," the CDFA warned in the report. According to recent news coverage, Asian jumping worms have been spotted in California with greater frequency of late.

Native to East Asia, particularly Japan and the Korean Peninsula, these worms began arriving in the United States in the early 1900s, tucked away in the soil of potted plants, according to the U.S. Department of Agriculture (USDA). Since then, the worms have wiggled their way across the U.S. and can now be found in at least 34 states.

Help #NYiMapInvasives find invasive species (like #JumpingWorm, in the video) in their Annual Mapping Challenge, now through 7/31! Find invasives, report them to iMap, & watch yourself rise on the leaderboard—maybe earn some fame. 😉 More at https://t.co/ciMWfdRlAe> pic.twitter.com/gLxml8v65I

— NYSDEC (@NYSDEC) July 15, 2021

Like an earthworm, the Asian jumping worm feeds on tiny pieces of fallen leaves that make up the topsoil, which is home to many tiny animals and microorganisms. And many plants depend on the leaf layer to grow and spread. But, unlike earthworms, the Asian jumping worm is never satiated.

According to the CDGA, these worms consume leaf litter and topsoil, leaving behind a grainy layer of soil resembling coffee grounds. Their destructive nature causes severe damage to forests.

"Jumping worms are voracious feeders and can devour such a thick organic mat so as to deplete it completely in 2-5 years," the CDFA has noted. "Also, by clearing the forest floors of understory plants and leaf debris, the worms encourage erosion and provide more accessible avenues for infection by other invasive species of organisms."

The worms, which have a light, milky-colored band around their bodies, which differentiates them from regular earthworms, have an annual life cycle, dying after the first hard frost of the season, according to a report from the University of Minnesota. The next generation survives the winter in cocoons in the topsoil hatching only once the soil temperature is consistently about 50 degrees F. In 60 days, they mature into full-size adults and can grow up to 8 inches long. Since they can quickly reproduce without a mate, their population is hard to control . . .

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