We’re sorry to be the bearers of bad news, but there’s an invasive species wreaking havoc on North American ecosystems that deserves our attention.
Amynthas agrestis goes by many names. They’re called “Alabama jumpers,” “Jersey wrigglers,” “crazy worms,” and most commonly, “Asian jumping worms.”
“Invasive Asian jumping worms got their name because of the way they thrash around,” Mac Callaham, a Forest Service researcher who specializes in soils, explained in a Southern Research Station blog post. “They can flip themselves a foot off the ground.”
If that weren’t already hard enough to swallow, jumping worms dine on humus, the rich, organic top layer of soil formed by dead and decaying small animals, insects, and leaf litter. Humus is essential to the survival of plants, fungi, and other soil life. A decline in humus also threatens birds and other wildlife that depend on soil-dwelling insects for food.
Callaham describes the worm’s appetite as “voracious,” and in some areas, the damage has already been done.
“Soil is the foundation of life—and Asian jumping worms change it,” he added.
Native to east-central Asia, these worms are believed to have been introduced to the U.S. in the early 1900s, likely as tagalongs in potted plants. They are considered invasive because they did not evolve alongside the species of the U.S., and because they harm other species in the ecosystem.
Initially spotted in Wisconsin and across the New England area in 2013, the worms have since spread into dozens of states and as far South as Savannah.
The worms can be either gray or brown, with a smooth cream or white collar that wraps entirely around part of their bodies. They move like a snake and sometimes appear to jump when disturbed. Look for soil with a similar appearance to coffee grounds. As jumping worms eat and excrete waste, the soil gets a unique texture like coffee grounds. (You can find more information about them here.)
Erin Buchholz, an integrated pest management specialist with the University of Minnesota Landscape Arboretum, said that jumping worms thrive in cooler, irrigated lands with plenty of mulch. In times of drought, which is not favorable for their survival or reproduction, they’ve thrived in irrigated gardens where moisture is guaranteed.
As far as distribution goes, Buchholz explained that the scientific community is reliant on the public to report sightings. This can be done through EDDMapS, a free and easy way to report different species that can be harmful to our environment. For Southern states, the phone app tied to EDDMaps is called SEEDN, or the Southeast Early Detection Network. Simply take a photo of the suspect species and report from your phone to alert a state agency representative.
Gardeners are advised to clean soil off all gear (tools, gloves, shoes, carts, etc.) before taking it to another yard. Experts also recommend removing soil from all plants before transporting them as bare root plants or potting into sterile potting soil.
“If these worms didn’t spread into forests and natural areas, they wouldn’t be such a problem,” Callaham concluded. “But unfortunately, they simply won’t stay where you put them. The best way to prevent future invasions is to avoid moving earthworms around.”