COMMON NAMES: Oak Leaf Sawfly, Sawfly, Tenthredinid Sawfly
SCIENTIFIC NAME: Order Hymenoptera, family Tenthredinidae, many species
SIZE: Adult--1/2", larva--about 1/4"
IDENTIFICATION: Adults are small wasps that cannot sting. The name comes from the sawlike structure at the end of the female's abdomen, used to cut into leaves to lay eggs. Larvae look like translucent slugs, usually yellowish green and shiny with black heads. Some are covered with a slimy material.
BIOLOGY AND LIFE CYCLE: Females lay eggs on the back side of leaves. Larvae hatch and feed on the tissue between the veins, causing a skeletonized effect. Larvae overwinter in cocoons.
HABITAT: Red oaks and white oaks primarily.
ECONOMIC IMPORTANCE: Damage is usually spotty on trees and not significant.
NATURAL CONTROL: Enemy insects. Biodiversity.
ORGANIC CONTROL: Microbial disease products, horticultural oil, and citrus oil products.
INSIGHT: You see some of this damage every year, but it never seems to be anything other than cosmetic and temporary. Some sawflies attack and damage fruit trees, elms, roses, and pines.