Abstract: The sawfly, Gilpinia massonianais a newly discovered destructive insect to Pinus massoniana Lamb in Chu Xian county Anhui Province. It has two generations per year and overwinter under litter layer as prepupae in cocoons;until next April it emerges into adult. The larvl stage is about 31-54 days,pupal stage 8 -11 days and adult's lift-span about 8-12 days. The eggs are laid individually in pine needle and hatch after 10-13 days, The sex ratio of the adults is 0.52-0. 48. Spetial pattern of larvae is aggregation distribution, and the total amount of pine needle eaten by the larvae is 2. 3g. The sampling method of cocoons is N = B(1.4221x-0.3518), N is total number of cocoons under each tree crown, B is number of cocoons within lm of tree crown from the base of the tree to the periphery of perpendicuar projection of tree crown, xmean size of tree crown. Because the body surface of the 4th instar larvae are covered with a thin large of white wax, it is effective to control 2-3 instar larvae with a smoke generating formulation of diesel oil +2.5% diecise or 20% Shamiejuzhi in mid-May and October.

Key words: Diprionidae, Pinus massoniana Lamb, Life habit, Distribution pattern, Control index and method