Sowbugs and pillbugs: occasional but destructive greenhouse pests

We hear periodic reports of sowbug and/or pillbug outbreaks in greenhouses and high tunnels in Pennsylvania. One such outbreak is occurring this spring at the Southeast Agricultural Research and Extension Center (SEAREC) in Lancaster County, and also in a nearby commercial greenhouse.

by Lee Stivers

Sowbugs and pillbugs are closely related, but they are not insects. Rather, these arthropods are related to crustaceans such as shrimp and crayfish. They feed primarily on decaying organic matter but are also known to feed on seedling roots and young stems in contact with soil or growing media. Because they do not regulate moisture loss well, they do not like to be in dry spots, but prefer a moist environment.

Photo by Sinclair Adam.

Persistent cloudy weather, as we have been experiencing, may contribute to sowbug and pillbug outbreaks. One approach to controlling these pests is spreading diatomaceous earth on floors or walkways, but be careful to use the appropriate PPE when using diatomaceous earth to avoid inhalation exposure. A number of insecticides (e.g. cyfluthrin, bifenthrin, carbaryl, cypermethrin, permthrin, lambda-cyhalothrin) can also be effective.

Source: eGroBlog