Common Pine Sawfly – Diprion pini

Common Pine Sawfly   Scientific Name:  Diprion pini Common Name:  Common pine sawfly, conifer sawfly Appearance:  Common pine sawfly is a thick-waisted sawfly of size 8 to 10 mm. It is brown in colour with red and white marking throughout. It also has a pair of antennae and two pairs of wings with distinct veins. The larva is long and ranges in size from 18 to 25 mm. Host Plants or Food: Common pine sawfly feeds on pine trees, especially ponderosa and pinyon pine. However, it may attack other pine trees as well as douglas fir. Territory: Throughout North America, Eastern USA and Western USA Mode of Damage:  They are leaf chewers and feed on needles, particularly old ones. Besides, it may also feed on the bark and acts as a stem and twig damager. Habits and Life History: Common pine sawfly females have a sharp ovipositor like that of a saw, hence called common pine sawfly. It cuts open a slit on the needles and lays eggs in there. The larva feeds on the outer needles; some even consume the entire needles to mature. Once it is ready for pupation, it drops to the ground and forms a cocoon in the soil among the pine litter. It remains dormant during the winter at one stage of its life, either in eggs or as a pupa. It produces 1 to 4 generations per year, depending upon the geography.