European Pine Sawfly

Plants Affected:

Images of This Insect:

European pine sawfly larvae (photo: Petr Kapitola) Bugwood.org

European pine sawfly adult (photo: Petr Kapitola) Bugwood.org

Description

Defoliation of pine trees and shrubs by clusters of European pine sawfly larvae is a common problem in Iowa during the month of May.  Larvae of this widespread pest are grayish-green with 2 light stripes and 1 dark stripe on each side of the body.  The legs and head are shiny black.  Full grown larvae, usually present by Memorial Day weekend, are about 1 inch long.

Damage

European pine sawfly larvae are gregarious and stay together in a cluster as they feed on the old needles from mugho, Scots and red pine trees and shrubs.  Because only old needles are eaten and not the new, emerging growth, defoliated trees are generally not killed.  Damage may be aesthetically displeasing, especially in Christmas tree plantations, and growth of the tree may be stunted.

Management