Issue 10, June 29, 2015


Sowbugs and pillbugs look like tiny armadillos and are commonly called roly-polies. Pillbugs roll up into a tight ball when disturbed. Sowbugs are flattened dorso-ventrally, with their upper surface consisting of wide plates connected by the underlying body. Sowbugs and pillbugs are crustaceans, being more closely related to crayfish and shrimp than insects. As such, they have two pairs of antennae, gills under the carapace, and ten pairs of legs. Some species of sowbugs are aquatic, being common in streams and ponds.


They are occasionally found in dry soil but their gills require their periodic return to moist conditions. When present in large numbers, they sometimes feed on seedlings and soft leaves. They primarily feed on decaying plant material and will build up to large numbers in moist dead turf areas and around sprinkler heads.

Reduction of dead organic matter and reducing moisture are the main methods of managing sowbug numbers. Being crustaceans, insecticides are unlikely to be very effective. (Phil Nixon)

Phil Nixon

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