A New and Significant Threat to Forests Observed on Fishers: Asian Jumping Worm

The Asian jumping worm, which can grow to eight inches, is identified by the whitish band that mostly circles its body near its head.

Dianne Crary in October reported the presence of “a lot” of invasive Asian jumping worms on her property along Equestrian Road. Unlike the familiar earthworm, which burrows into the ground, this Asian invader, when disturbed, writhes and scatters across the surface of the soil. If touched, it thrashes wildly and may shed its tail.

Living on the surface in woodlands, Asian jumping worms quickly devour fallen leaves and other organic material, turning the surface into loose soil resembling coffee grounds. The loss of leaf litter destroys long-lasting nutrients vital for the survival of trees. Additionally, altered soil inhibits the establishment of tree seedlings and is inhospitable to many native plant species.

Asian worms reportedly have reduced leaf litter in hardwood forests by 95%. A naturalist observed an infested forest in Cortland County, New York, and said that “it was almost entirely bare soil.”

As with so many invasive species, these worms are adaptable and difficult to stop. They are parthenogenetic: they can reproduce without fertilization. The introduction of a single individual is enough to launch a jumping worm invasion. The worms have an annual life cycle. They die in the fall, but leave tiny cocoons that winter in the soil.

What to do? According to the Cornell Cooperative Extension of St. Lawrence County, “Asian worms are commonly spread through the horticulture trade, both in containerized plants, and especially mulch, which they love. Check bulk mulch before purchasing, and maybe think twice about getting fill delivered to your property.”