How can I mitigate damage from jumping worms found in a compost pile?

Question:

I have recently discovered what I believe to be jumping worms in my compost pile. I am very concerned about my plants and soil. How much damage can I expect and is there anything I can’t do to mitigate?

Answer:

Jonathan Foster, Home Horticulture Outreach Professional

The Asian jumping worm is rapidly becoming quite a headache for home gardeners, so you certainly aren’t alone in this dilemma.

You can read more about the pest in this UMass-Amherst Q&A on Amynthas and Metaphire worms. Unfortunately, there isn’t yet a consensus on a safe and effective management technique, other than removing them by hand using the mustard soaking explained in my included links. Obviously, if your infestation is on a larger scale than that allows, that idea may not be feasible for you, but it could work in a compost pile–and it’s important not to add infested compost to your other beds, as prevention is our best defense at the moment. There is some evidence that biochar and diatomaceous earth may mitigate the pests when mixed into the soil (read about the use on the UPenn Extension page on jumping earthworms)–this will affect beneficial earthworms, too, but is presumably less harmful when added to the soil. Tea seed meal is often mentioned online as a treatment, but the Cooperative Extension does not recommend its use, as early studies have shown it to be ineffective and this is an off-brand use, bringing the legality of such a process into question.

A couple of other links for you:

UMaine Cooperative Extension page linking to advice on plant sales

State of Maine page on Asian jumping worms

I know this is depressing news, and part of the work we’re doing at the Extension right now is to keep home gardeners optimistic and hopeful about this growing pest–don’t give up! There is active research being conducted, so hopefully we will have some better advice for you and others in the near future.