by Cathy Krar, Master Gardener
Not again! Invasive fish, invasive plants, invasive insects, invasive pathogens and now our native ecology is being threatened by invasive Asian Jumping Worms.
Asian Jumping Worms were first confirmed in Ontario in 2021 in the Windsor, Hamilton and Toronto regions but they are on the move. These worms have a voracious appetite for organic matter and easily outcompete other worms for soil nutrients. They effectively prevent the surface litter from decomposing naturally and render it unable to hold onto moisture. The worm castings (or poop) left behind resembles clumpy, dried coffee grounds and degrades the quality of the soil. Native plants struggle and the root systems of trees are exposed over time. The remaining nutrients are easily washed away during rainfall or irrigation contributing to increased soil erosion.
These non-native worms pose a massive problem if they get into our gardens, lawns, farms, and especially if they push out the native understory in our forests.
Adult Asian Jumping Worms are about 12 inches long with a smooth body and around 14-16 segments. What is distinctive from the earthworm is the milky white clitellum, or collar that is located near the head of the jumping worm. This contrasts with other wormsthat have a pale pink ring about a third of the way along the body. Asian Jumping Worms will thrash violently if picked up or disturbed, even to the point of dropping off part of the tail.
These worms are survivors; they lay up to 20 hardy worm cocoons each month without ever needing a mate. While the parent worm dies over the winter, the peppercorn or smaller sized cocoons survive the cold winter temperatures. During May and June, the young juvenile hatchlings appear and they grow into adulthood from July to October. They are pretty small when they first hatch so late summer if the best time to find and identify the adult Asian Jumping Worm.
If you do find one of these invasive worms destroy it by drowning in isopropyl alcohol. Or, seal in clear plastic bags and bake in direct sunlight. Lessen the risk of leaving behind other worms by solarizing the garden area with clear plastic for two to three weeks. If you do suspect an infestation in your yard, mix one third of a cup of powdered mustard with a gallon of water and pour over the soil surface. This will bring them to the surface.
Because the cocoons are so small there is a high risk of gardeners and the horticultural industry inadvertently spreading these invasive pests by the movement of soil, mulch, compost or the transfer of plants. The cocoons are known to hitch a ride in shoe treads or the tires of landscaping equipment. Although there is no direct evidence, there is some concern around the sale of these worms as fishing bait as a major spreader.
While most worms in Ontario are non-native, Asian Jumping Worms cause much more damage and spread more quickly. Currently there are no known controls or pesticides to stop these invaders so preventing the spread is important: Make sure to clean your footwear after visiting any public or private garden or any natural areas; park vehicles on paved surfaces; check any new soil, compost, or mulch for evidence of these worms; isolate and inspect all new plants you intend to introduce to your garden; never use Asian Jumping Worms as fish bait; and dispose of any unused bait in the garbage not on natural lands.
Consider this: You can be a part of the detection team. Report any sightings along with picture evidence to Ontario’s early detection mapping at www.eddmaps.org/ontario/ or call 1-800-563-7711.
A rapid response to the spread of these non-native invaders is critical. With everyone on the look-out and practicing preventative measures, we might be able to kick this can of worms out of here!
This series of gardening articles are brought to you by the Simcoe County Master Gardeners, members of the Master Gardeners of Ontario. For more information, visit www.simcoecountymg.ca.