Look Now for Pine Sawfly

Pine sawflies have hatched in the Manhattan area. If you have had a problem with this insect before, check your pines for the beginning stages of damage. When these worms are small, they cannot consume a complete needle, so they rasp off the top layer of cells. This leaves individual needles brown and twisted. Look for this damage to pinpoint where sawfly larvae are feeding. The larvae are gregarious, so a number of larvae will be found close together. As the larvae mature, they will consume whole needles and can virtually strip a tree. This happens before new needles expand, so the tree is rarely killed. The pine sawfly prefers Scotch and Mugo pines.

A number of insecticides can be used for control including spinosad (Captain Jack’s Deadbug Brew; Fertilome Borer, Bagworm, Leafminer and Tent Caterpillar Spray), acephate (Hi-Yield Acephate Systemic), cyfluthrin (Bayer Lawn and Garden Multi-Insect Killer), malathion and permethrin (numerous trade names). Horticultural oils and insecticidal soaps also are effective because of the soft skin of sawfly larvae. Bob Bauernfeind, in entomology, has an excellent article on pine sawfly that gives much more detail at



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