Time to scout for pine needle scale
Editor’s note: This article is from the archives of the MSU Crop Advisory Team
Alerts. Check the label of any pesticide referenced to ensure your use is
included.
If you
have Scotch pine trees that had high densities of pine needle scale
last year in your fields, you should be scouting your trees right about
now. The first generation of eggs usually hatch around 250-400 degree days base 50.
It's not necessary to apply an insecticide immediately after you see
the reddish-colored crawlers. In fact, it's best to let the crawlers
settle down and establish feeding sites on the needles (the hyaline
stage – 400-500 GDD base 50).
At this point, the immature scales are exposed and have not yet
secreted the white, waxy protective armor. If you can apply your spray
at this point and if you get good coverage, you should get good control.