White Pine Weevils
Facts, Identification & Control
As is suggested by their name, white pine weevils most commonly infest white pine and spruce trees. However, specimens may also be found on black spruce and lodge pole pines. Adults are easily identified by their unique rust coloration. They measure between 6 to 7 mm in length and feature brown and white scales along their wings. Weevils are equipped with long, beaklike snouts.
Behavior, Diet & Habits
Feeding punctures in the bark of trees are early signs of infestation. These punctures appear in early summer months and may ooze a light resin. In May and June, they will begin to scab over. Most damage caused by a white pine weevil infestation is due to the feeding habits of larvae, which are white with brown head markings. They infest the roots of trees and can lead to the death of the host. Most infested trees wilt, while some grow crookedly or exhibit stem deformation.
White pine weevils reproduce only once each year. Adults emerge in early spring and move to infest host trees. These weevils mate in the fall and eggs are laid in host trees in the spring. Eggs hatch within 10 days, but adults do not remain with their larvae.
Signs of a White Pine Weevil Infestation
Droplets of resin and small holes in the trees may indicate white pine weevil activity.
A comprehensive pest control plan is necessary to combat white pine weevil infestations. Direct control through the use of pesticides may be necessary but is not advised without first consulting a specialist in tree pest control. Diversification of the tree population can also prove effective.