Sevin, Dursban or Astro are recommended as preventive insecticide sprays. Pitch nodules at wound site are round, smooth and light purple or red. Older needles are generally attacked. Needles turn yellow, die and drop. Repeated attacks can kill young trees, weaken older trees.
Weakened trees are more susceptible to bark beetle attacks.
The white, cottony wax on the eggs can be quite visible in heavily infested trees. Premature death of attacked needles. Predatory and parasitic wasps keep populations low. Use the silk produced by the pupae to time emergence. Older needles are not affected.