A spray of malathion or spinosad, which are among the compounds registered for control of this pest in Connecticut, as needed in August or September will protect the needles from injury. Consult the label for dosage rates and safety precautions. Eastern spruce beetle, Dendroctonus piceaperda . This small bark beetle emerges in June and July in large numbers from small round holes, resembling shot holes. Weak trees of the native red, white, and black spruce in particular are infested, and the insect seems to prefer trees a foot or more in diameter.
Infested trees show exuding gum more or less mixed with sawdust on the trunk.
The females lay eggs in June and July and the grubs tunnel under the bark while feeding, overwintering in the burrows as adults or in a partially grown condition and completing their development the following spring. There is one generation each year. Infested trees should be cut, and the bark removed before the middle of May to prevent beetle emergence. This helps to protect adjacent uninfested trees from attack. Maintain adequate irrigation to trees to prevent infestation.