August 3, 2005

Christmas Tree Scouting Report - August 3, 2005

The second generation of pine needle scale crawlers are beginning to hatch on Scotch pine in Franklin County. Most of the crawlers are still under the white protective covering of the female adult. In Dauphin County only eggs of the pine needle scale were found. This second generation is a little late this year, which shows you cannot go by a calendar date. Scouting your own fields is the best way to time your sprays most effectively. The eggs and crawlers of pine needle scale are reddish-pink in color. Once the crawlers emerge from beneath the adult cover and begin to settle and start to feed, it looks like paprika was sprinkled over the needles.

It is best to wait until all eggs have hatched and crawlers have emerged and begun to feed but before they start producing the hard, white armored covering before applying an insecticide. If scale populations are low and/or trees are close to harvest, control may not be necessary. There are a lot of natural enemies out there that will attack pine needle scale. Scales with round exit holes in the hard white covering is evidence that parasites are at work.

Eggs of Cryptomeria scale are beginning to be laid under the female cover on Fraser fir in Lebanon County. In Dauphin County a few eggs were beginning to hatch. Flipping over the scale covering with your nail or a pin will expose the tiny lemon yellow jellybean shaped eggs that can be seen with a 16x hand-lens. Eggs hatch in about two weeks from the time eggs are laid. The most effective time to control armored scale is at egg hatch when crawlers are present.