Adult insects are roughly cylindrical and 3-5 mm long with shiny black heads and wing covers ranging from reddish brown to black. They resemble other common native bark beetles so positive identification should be made by trained experts. Adults spend the winter in the lower stems. In the spring, they emerge and crawl or fly to nearby dead or dying pines where they mate and lay eggs beneath the bark. Eggs hatch, and the larvae remain under the bark to feed for 6-8 weeks and then pupate.
Hungry adults emerge, and maturation feeding is done in young shoots of pines.
Each insect makes a hole 2-3 mm in diameter in the bark, as a point of entry into the shoot, and mines the tissue within for up to 10 cm. When damage is sufficient to cause wilt of a shoot, the insect may lose interest in it and find another. On Scots pine, infested shoots become discolored, and may die as early as late June, though often remaining attached to the tree. On Austrian pine, infested shoots remain alive and green much longer. In early July, they can only be recognized when uninfested shoots expand to full size while infested shoots remain stunted.