Pest Activity -- March 31, 2000

Pest Activity > Pest Activity Archives > March 31, 2000

Welcome to the Woody Ornamental Pest Scouting Report for Western Pennsylvania for March 31, 2000, brought to you by Penn State Cooperative Extension. This tape will be updated weekly with growing degree day counts and insect activity through the end of June. If you would like an email copy of this report, send your request to mcm2@psu.edu.

As of March 29, the following growing degree days using a base temperature of 50 degrees have accumulated:

Fox Chapel	73
Butler	69
Uniontown	90
New Stanton	70

European Pine Sawfly larvae have hatched in Allegheny and
Westmoreland counties and the 1/4 inch long larvae can be found
feeding on last year's terminal growth. Their preferred host plants
are Scotch, Japanese Red and Mugho Pines. At this time the larvae are confined to a localized area and a spot treatment or physical removal will provide control.

The immature adults of Cooley Spruce Gall Adelgids remain active on Douglas Fir in Westmoreland County. Feeding damage from his pest will cause bent or distorted needles on Douglas Fir and galls on the terminal growth of Colorado Blue and Oriental Spruce. Now is the time to check for the presence of the black colored adults on the needles of Douglas fir and Colorado Blue Spruce to determine if a spring control measure is warranted. Controls should be applied before the black colored females produce the white waxy filaments that cover their bodies and reduce pesticide efficacy.

Eastern Spruce Gall Adelgid, the pest responsible for the pineapple shaped galls on Norway Spruce, is also active now. Trees with a past history of this pest should be scouted at this time.

White Pine Weevil feeding was observed in Westmoreland County and Beaver counties this past week. This pest is responsible for killing the terminal leader on Eastern White Pine, Spruces, and occasionally Douglas Fir. Glistening droplets of fresh sap found on the terminal leaders of white pines is the result of feeding by adult males and females. Registered insecticides applied according to label directions should be directed to the tops of the trees at this time, before the females lay eggs in the terminal leaders.

Eriophyid mites continue to be active on hemlocks in Westmoreland and Beaver counties. High populations of this pest will cause needles to yellow before dropping. If you noticed this occurring in the landscape or nursery last year, check now for small worm-like creatures with two pairs of legs. Eriophyid mites are much smaller than spider mites and a hand lens is required for detection. Registered insecticides applied according to label directions should be used at this time.

The next page update will be on Friday, April 7th.