By Susan Neul
Many Becket gardeners are starting to discover the dreaded Asian jumping worm in their flower gardens and planters, but the reality is that these worms have been around for a quite a while. Before the recent publicity, gardeners probably thought they were seeing the common and very beneficial earthworm.
The two worms do indeed look similar at first glance, but one does far more dancing when disturbed than the other. The common earthworm does a languid waltz while the jumping worm channels John Travolta. The earthworm is bigger and its lighter-colored collar (clitellum) is raised, while the jumping worm’s collar is flush with its body. But the easiest way to decipher which is which is just to look at their movements. The jumping worm does indeed jump all over the place when exposed to light.
So why are these jumping worms considered to be troublemakers? Aren’t worm casings full of nutrients? The problem is that these worms are voracious eaters of the rich organic material on forest floors, and, unlike the earthworm who burrows and deposits its casings into the soil, the jumpers leave theirs on the surface where roots can’t reach the nutrients. Forests with huge invasions no longer have understory plants as a result.
What are the implications for the home gardener? Having worms in a planter or bed will not affect the beauty of your carefully chosen flowers over the summer. The issue is that as the gardener cleans the bed in the fall and throws the dead plants onto the compost pile, the worms and their egg-bearing cocoons migrate to the forest floor. Worms and eggs can also move from garden to garden as enthusiastic gardener friends and neighbors divide and share their plants. Adult worms cannot survive the cold, but their eggs have no problem. And the eggs, which start hatching as soon as the soil hits 60°, can also survive for several years before they hatch.
If you don’t already have jumping worms in your beds, then keep it that way by inspecting the soil of all purchased plants before planting. That being said, it can be hard to see the cocoons. The only way to be sure no eggs have hitched a ride is to rinse all the soil off the roots of purchased plants before planting. Alternatively, a gardener can sift through beds and planters and pick out all the worms before they start laying eggs in August; but few gardeners will want to do this. The best thing a gardener can do is to keep from spreading the worms. Throw dead plants and used soil into an enclosed compost bin, and only use that compost after sterilization.
For more information see https://www.umass.edu/agriculture-food-environment/landscape/fact-sheets/invasive-jumping-worm-frequently-asked-questions.
