Jack pine budworm

Jack pine budworm - Larva on male flower-bearing jack pine shoot
  • Latin name: Choristoneura pinus Freeman
  • French name: Tordeuse du pin gris
  • Order: Lepidoptera
  • Family: Tortricidae




Needle, Male flower, Cone, Bud

Damage, symptoms and biology

Defoliation caused by jack pine budworm larvae occurs primarily in the upper part of the crown. During the season, cut needles and larval frass tangled in strands of silk can be seen on annual shoots. Damaged foliage dries out and turns reddish brown.

The consequences of a jack pine budworm attack are the destruction of the upper part of the crown, resulting in competition between lateral branches for the establishment of a new apical leader. This causes growth loss and, in cases of repeated severe infestations, may result in tree mortality.

In June, before the new foliage appears, the young larvae may feed on staminate flowers, cones, old needles and even the bark of twigs. The larvae are wasteful feeders: they cut the needle at the base and eat only the base portion, leaving the rest of the needle tangled in silk along with frass and other dried out needles. Larval development occurs entirely in a shelter composed of the foliage of a few twigs connected by loose strands of silk. The caterpillar generally pupates on the same shoot.

The eggs are laid in July on needles in the upper part of the crown and hatch about 10 days later. The newly-hatched larvae do not feed and spin small silk shelters (hibernacula) in bark crevices in which they overwinter.

Life cycle (East of the Rockies)

Life cycle (East of the Rockies)
Stage/Month J F M A M J J A S O N D

Other information

Native to North America, the jack pine budworm was long confused with the spruce budworm, Choristoneura fumiferana (Clemens). It was not until 1953 that the jack pine budworm was recognized as a separate species.

This insect occurs throughout the range of its principal host, jack pine. In Canada, it is found primarily in Ontario, Manitoba and Saskatchewan. In the United States, it also occurs in the states bordering the Great Lakes. Jack pine budworm damage causes major economic losses in jack pine stands and Scots pine plantations.

Canadian Forest Service Publications

Jack pine budworm

Diet and feeding behaviour

  • Heteroconophagous : Feeds occasionally on seeds and cones, but usually lives and feeds on stems and needles.
    • Borer: Bores into and feeds on the woody and non-woody portions of plants.
  • Phyllophagous : Feeds on the leaves of plants.
    • Webworm: Spins a silk shelter in which to hide or feed.
  • Pollinivorous : Feeds on pollen.
    • Webworm: Spins a silk shelter in which to hide or feed.
Information on host(s)

Main host(s)

Jack pine, scots pine

  • Jack pine budworm Newly emerged moth near its pupal case
  • Jack pine budworm Larva on needles
  • Jack pine budworm Pupa in its natural position, near its last larval molt
  • Jack pine budworm Egg cluster on jack pine needle
  • Jack pine budworm Larva on male flower-bearing jack pine shoot
  • Jack pine budworm Moderately defoliated jack pine stand
  • Jack pine budworm Severe defoliation on jack pine tree
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