| Table: Diagnosis and Control of European pine sawfly | ||
| Pest Identification | Host Plants | Damage Symptoms |
| European pine sawfly
Neodiprion sertifer Diprionidae |
Mugo, scotch, red and jack pine are preferred. White, Austrian and ponderosa pines can also be fed upon. | Larvae feed in compact groups, especially when young. They feed only on previous
years needles and will eat all the needles on one branch before moving to another branch. Feeding damage occurs very early in the spring. Infested trees rarely die because new needles are never eaten. However, infested trees can have very thin crowns due to the lack of old needles. |
| Monitoring | Control Options | Pesticides |
| Look for larvae very early in the spring, well before bud burst has occurred on host trees. Larvae will occur in clumps and the missing foliage on infested branches is generally very obvious. |
Physical: Clumps of young sawflies can be removed by hand, this is very effective on
smaller trees and when larvae are young. The larvae disperse on the tree as they age. Biological: A virus often infects and kills this sawfly. Infected larvae die and hang head down attached by their prolegs to a needle or twig. These dead larvae can be collected and soaked in non-chlorinated water. This solution can be applied to developing sawfly colonies the following spring. Chemical: Insecticidal soaps should kill larvae and can be sprayed directly to groups of young larvae. |
Insecticidal soap Acephate Carbaryl Chlorpyrifos Diazinon Malathion |
| Description and Life History | ||
|
Description: Larvae are gray-green with a black head and legs. They have a single light stripe down the back,
two light green stripes and one dark green or black stripe on each side and are 18-25 mm in length when full grown. Life history: This sawfly overwinters as eggs embedded in previous years needles. Egg hatch occurs in the early spring, mid-April through mid-May, and larvae feed on old needles. After feeding is completed larvae drop into the soil where they pupate. Adults emerge, mate and egg-laying occurs through the fall. Eggs are layed in previous years needles at the ends of branches. | ||
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