Pest Activity -- April 27, 2001

Pest Activity > Pest Activity Archives > April 27, 2001

Welcome to the Woody Ornamental Pest Scouting Report for Western Pennsylvania for April 27, 2001, 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 April 25, the following growing degree days using a base temperature of 50 degrees have accumulated:

Wexford	145
Uniontown	240
New Stanton	171
Butler	90

Summer... Winter....Summer.....Winter.. What's it gonna be?

After a slow start, from a growing degree day standpoint, we have caught up and in some cases surpassed the numbers from the past year 5 years. While the frigid morning temperatures earlier this week burnt back some newly emerging foliage, it did little to deter insect activity.

It's now too late to get maximum control with insecticidal sprays for Cooley Spruce Gall Adelgids on Douglas Fir and Colorado Spruce for most parts of southwest Pennsylvania. The adelgid stem mothers observed in Westmoreland county are producing clutches of oval eggs under masses of white waxy threads. If you are located further north, before applying sprays, examine the cottony masses at your location. If eggs are present, you will not achieve maximum control with a spray and may want to wait for the next control window for Cooley and Eastern spruce adelgids in September and October. Feeding damage from this pest will cause bent or distorted needles on Douglas Fir and galls on the terminal growth of Colorado Blue and Oriental Spruce.

Birch Leafminers adults were observed in Allegheny county this week and they will be laying eggs in the expanding leaves over the next couple of weeks.

Inkberry leafminer, a key pest of Ilex glabra or inkberry holly has also emerged and control sprays should be applied at this time. This pest also has a second generation that occurs from mid-August to mid September.

Boxwood Psyllid nymphs were observed this past week in the City of Pittsburgh. The feeding activity of this pest causes the cupping of the terminal leaves on boxwoods and treatment should be applied now before the nymphs become adults

Pine Spittlebug nymphs were observed this past week on white and Scotch pines in Westmoreland County. This pest rarely warrants the use of insecticides for control.

White Pine Weevil eggs were observed in Westmoreland County again this past week, thus closing out the window for control of this pest for many parts of southwest Pennsylvania. This pest is responsible for killing the terminal leader on Eastern White Pine, Spruces, and occasionally Douglas Fir.

Eastern Tent Caterpillar tents are approaching 5-6 inches in length and the larvae observed in Westmoreland county measured 3/4 inch long. Please check the Penn State Woody Ornamental Insect and Disease Management Guide for insecticides labeled for their control. If using a contact insecticide, be sure to apply it when the caterpillars are feeding outside of the tents.

European Pine Sawfly larvae in Westmoreland county are 1/4 inch long at this time and 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.

Eriophyid mites continue to feed on hemlocks in southwest Pennsylvania at this time. 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 tape update will be on Friday, May 4th.