Illinois gardeners are eager for the new growing season. While doing the usual preparations and tasks, home gardeners should be aware of an invasive species wriggling across the Midwest, the jumping worm.
Jumping worms are non-native earthworms that can easily be spread by humans, but there are steps gardeners can take to reduce risks. Also known as Alabama jumpers, crazy worms or snake worms, this invasive species is named for its unique, active movements. First discovered in Illinois in 2015, the pest now has been confirmed in more than 40 counties across the state.
Jumping worms often are found in the leaf litter or mulch layer, or in the top 3 to 4 inches of soil in wooded areas, garden beds and lawns. Once established, jumping worms can damage plant roots, lawns or ornamental gardens.
The worms are voracious eaters that decrease soil quality and reduce organic matter. This is caused by their castings making up a higher and higher percentage of the soil. Over time, the soil begins to look like coffee grounds. Since this sign is delayed and the worm’s microscopic eggs can survive Illinois winters, gardeners may unknowingly have them or spread them.
Don’t panic. While the worms have a huge impact on the fragile soil profile of Illinois forests, effects to the garden or yard can be addressed. Jumping worms do not disperse very fast on their own. Gardeners can help by using heat-treated commercial compost or mulch; cleaning off equipment and shoes, especially if working at multiple garden sites; and not sharing home compost, mulch or plants.
Dividing perennial plants is a good gardening practice. However, sharing those perennials with neighbors or donating them to plant sales may not be the best thing to do now.
Before transplanting in the same yard, gardeners can remove soil and wash plant roots to prevent spreading eggs. It is still safe to buy plants from garden centers or catalogs or those that are started from seed and grown in pots.
Adult worms can be removed when found, usually from June to the first freeze. Jumping worms are larger than other earthworms, about 4 to 8 inches long, with glossy skin and a more rigid, stiff structure. They thrash when touched or disturbed, giving them their unique nicknames.
The main identifying feature is the clitellum, or band, which is smooth, not raised, and completely circles the body. Often it is a milky white color starting at the 14th segment, earlier than other species.
If you have jumping worms, these mitigation efforts are needed, along with fertilization and mulching to maintain organic matter for plant health. Realistically, it is going to be hard to get rid of an active population until research provides better practices to manage them.
This does not mean gardeners need to abandon their yard projects or find a new hobby. Continue to grow, divide, and enjoy the many wonderful blooms and harvests throughout the season.
Learn about how to identify and report jumping worms at go.illinois.edu/JumpingWormsGuide.
Have a question for the Master Gardeners? Residents can contact the Kendall County Master Gardener volunteers from 9 a.m. to 12:30 p.m. on Monday, Wednesday, and Friday by calling 630-553-5823, visiting 7775B Route 47, Yorkville, or emailing uiemg-kendall@illinois.edu. For helpful hints on what to include in your email, visit go.illinois.edu/HelpDeskMGdkk.