Pest Activity -- May 25, 2001

Pest Activity > Pest Activity Archives > March 25, 2001

Welcome to the Woody Ornamental Pest Scouting Report for Western Pennsylvania for May 25, 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 23, the following growing degree days using a base temperature of 50 degrees have accumulated:

Wexford	410
Uniontown	573
New Stanton	448
Butler	347

Eunoymus Scale eggs have hatched and crawlers were observed in the city of Pittsburgh this past week. Some of their common hosts plants include boxwoods, English Ivy, privet and pachysandra and Euonymus fortunei. Multiple pesticide applications may be required to control this pest so be sure to examine plants to evaluate the effectiveness of your control measures.

Lacebug nymphs were spotted on Rhododendron in Wexford and on Azaleas in Westmoreland County this past week. It is beneficial to prevent lacebug damage on broadleaf evergreens such as Azaleas, Rhododendron, Pieris, Mt. Laurel and Pyracantha early in the season because these plants will retain the unattractive foliage through more than one growing season.

Feeding punctures caused by the Native Holly Leafminer were observed again this week on Ilex opaca, American Holly in Sewickley and Wexford. No adult females or young mines were observed but should be appearing in the next couple of weeks. Damage to foliage

Four-lined Plantbugs continue to feed 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.

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.

 

 

 

 

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

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