Pest Activity -- May 18, 2001

Pest Activity > Pest Activity Archives > March 18, 2001

Welcome to the Woody Ornamental Pest Scouting Report for Western Pennsylvania for May 18, 2001, brought to you by Penn State Cooperative Extension and the PA IPM Program.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 May 16, the following growing degree days using a base temperature of 50 degrees have accumulated:

Wexford	335
Uniontown	490
New Stanton	372
Butler	280

Feeding punctures caused by the Native Holly Leafminer were observed on Ilex opaca, American Holly in Sewickley and Wexford this past week. The adult females will soon be laying eggs in the new growth so control applications should be applied at this time. Damage to foliage

Four-lined Plantbug damage was observed on numerous perennials this past week in Allegheny county. Their feeding on the upper leaves of many herbaceous perennials results in numerous 1/16" brown spots.

Pine Needle Scale crawlers observed in the New Stanton area are beginning to settle and under go their color change from a bright red to a yellowish-green color, but have not started to produce their white, waxy protective covering. Crawlers in the Sewickley area are still bright red and beginning their migration.

European Pine Sawfly larvae observed in Westmoreland county are one inch long and quickly devouring last year's terminal growth on Scotch, Japanese Red and Mugo Pines.

Damage from Birch leafminer larvae is evident in all parts of southwest Pennsylvania. A systemic insecticide should be used to kill the developing larvae at this time.

Spruce spider mite remain active on conifers. Some of their preferred hosts are spruce, arborvitae, junipers, hemlocks, and Douglas-fir.

Boxwood Psyllid nymphs and adults were observed again in Pittsburgh this past week. Their feeding damage results in the cupping of the terminal leaves. Treatment should be applied now before all the nymphs become adults.

Eastern Tent Caterpillars observed in Allegheny andWestmoreland counties this past week have left their tents and are looking for places to spin their yellowish cocoons.

Sphaeropsis Tip Blight -- Photo courtesy of Michael Masiuk

If Sphaeropsis Tip Blight previously called Diplodia) was a serious problem last year on Mugo, Scotch, or Austrian Pines, fungicide applications should be applied on a 10-14 day interval until the needles reach full size.