Eastern pine shoot borer
Quebec, Ontario, Manitoba
Damage, symptoms and biologyThe reddening and wilting of annual shoots in the upper part of the tree are symptoms of attack by eastern pine shoot borers. The larvae tunnel into the terminal leader or lateral shoots. The damaged current-year shoots tend to be more easily broken off by the wind. Severe attacks of the insect do not cause tree mortality. However, the loss of needles and the reduced size of the terminal leader affect the appearance of the trees.
The adults emerge in May and deposit their eggs on needle sheaths or on developing current-year shoots. On hatching, the larva begins to bore into the pith of the new shoots towards the base of the twig. At a later stage, the larva turns in the opposite direction to expand the tunnel in the young twig. When mature, the larva chews an exit hole through the bark and drops to the ground where it spins a cocoon in which it pupates. Winter is spent in the pupal stage.
Life cycle (East of the Rockies)
Other informationA species native to North America, the eastern pine shoot borer occurs throughout the range of white pine. It feeds primarily on young trees in open areas and plantations. If damage is severe in pine Christmas tree plantations, the marketability of the affected trees is compromised during the year in which the infestation occurs.
Damage by the eastern pine shoot borer can be limited by pruning out and destroying affected shoots before the larvae migrate to the ground.
Canadian Forest Service Publications
Diet and feeding behaviour
: Feeds on woody tissues (wood).
- Borer: Bores into and feeds on the woody and non-woody portions of plants.