Pests of Live Trees. Bark beetles (Figure 3) are among the more common boring insects detected in declining evergreens and spruce in urban and rural areas. Symptoms include holes as thick as a pencil lead along the main trunk and major limbs. ... Pine sawyer beetles (Figure 4) are often reported on white and Scotch pine.
Applying insecticidal soaps like Bonide Insecticidal soap. can help control the larvae, and insecticides like Permethrin SFR can be used to prevent the adults from laying eggs. Saturating the the soil at the tree's base with insecticide is also recommended to kill the grubs still burrowing there.It’s an endless battle. The Doctor ?