Spruce Beetle (Dendroctonus rufipennis)
Latin Name: Dendroctonus rufipennis
Common Name: Spruce Beetle
Appearance:
Adults are cylindrical, hard-bodied insects with black-brown or dark reddish wing coverings. They are small, measuring four to seven millimeters (approximately half a millimeter) in length.
Adult spruce beetles burrow roughly 12cm long tunnels under the bark and lay approximately 100 eggs per gallery.
The larvae hatch and feed beneath the bark, generating fan-shaped tunnels.
Host plants:
Spruce beetles affect various native North American spruce species (Picea).
Territory:
This bark beetle may be found in North American spruce woods.
Damage caused by Spruce Beetle:
Needles on afflicted trees may become a pale yellowish-green hue and fall to the ground after strong winds, although they seldom turn rust. Boring dust, created as beetles bore new entrance holes, can build in bark fissures and around the tree’s base. Resin streams along the main stem are frequently connected with freshly injured trees.
Life history and Habits:
Spruce beetles must overwinter once to develop completely. Mature adults emerge and assault new host trees from late May through early July. Some juvenile spruce beetle adults may emerge from the tree in the fall to overwinter in the soil near the tree’s base. Adult spruce beetles burrow 12cm long tunnels under the bark and lay roughly 100 eggs per gallery. Larvae hatch and feed beneath the bark, creating fan-shaped tunnels.
