The jumping worms (Amynthas spp.) is a term given to species in the family Megascolecidae. In New York three species (Amynthas agrestis, Amynthas tokioensis and Metaphire hilgendorphi) often co-invade a site. Like all earthworms, jumping worms were unintentionally introduced to North America, likely through infested nursery stock.
While they are now widespread throughout much of the US, they have only recently been documented in northern hardwood forests in WI, MN, and NY States. There are sightings reported to iMapInvasives in St. Lawrence County in Colton and Oneida County near Oneida Lake.
Often, earthworms are considered beneficial to soil health. This is true for European earthworms in some places such as gardens and agricultural fields but is definitely not the case for invasive Asian jumping worms. Jumping worms reproduce twice as fast as European earthworms, and consume soil organic matter so effectively and fast that the soil becomes very palletized, which dries out quickly. For a plant it is like trying to grow in gravel instead of soil. Plus, jumping worms contain heavy metals that may harm predators like birds, amphibians, and other worm species.
The loss of leaf litter and the erosion and subsiding of soils that result from a jumping worm infestation leads to greatly reduced forest regeneration and a loss of biodiversity across trophic levels including amphibians, birds, beneficial fungi, and understory plants. Jumping worms create bare soil in the forest, which paves the way for unwanted invasive plants such as garlic mustard and buckthorn. Watch a short video to learn more.
Jumping umping worms do not need to mate, and a single one can start a whole new population. They are easily spread through the movement of nursery stock, compost, vermiculutre, fishing bait, topsoil, well as gardening and landscaping equipment and shoe treads.
Jumping worms will thrash wildly when handled. Click here to view a video of this behavior.
Clitellum (band near the head)
The clitellum completely encircles the body, is milky white to gray, and smooth to the body (not raised) and located more towards the head. The common non-native European species have a raised, reddish clitellum that is more towards the middle of the body.
Granule soil that resembles coffee grounds is a sign of a jumping worm infestation.
Currently, there are no methods known to control earthworms. Therefore, preventing their spread is most important. Below are some precautionary steps that can help slow their spread.
The best time to find jumping worms is late August or September when they have reached adult size. Search underneath leaf litter above the soil in forested and urban areas.
Note the location in which the worm was found.
Take close up photos of the specimen. Be sure to include a close up of the band around the body of the worm (clitellum).
Report sighting to iMapinvasives.org or your local Cornell Cooperative Extension.
You can check your property for jumping worms by using a mustard pour.
Title photo by Susan Day / UW Madison Arboretum
Asian worm clitellum photo by Wisconsin Master Gardener, European worm clitellum photo by Holger Casselmann
Granular soil photo by Bernadette Williams/ Wisconsin DNR
Mustard pour photo by Karen Ceballos, NY Master Naturalist Program Assistant, Cornell Department of Natural Resources