Red pine cone beetle

Red pine cone beetle - Resin flow near adult entry hole

Latin name: Conophthorus resinosae Hopkins
French name: Scolyte des cônes du pin rouge
Order: Coleoptera
Family: Curculionidae

Synonym(s): Conophthorus banksianae McPherson

Distribution

New Brunswick, Nova Scotia, Prince Edward Island, Quebec, Ontario

Micro-habitat(s)

Twig, Cone, Annual shoot, Bud

Damage, symptoms and biology

The primary pest of red pine cones, the adult attacks second-year cones early in the season. In affected cones, the adult and larvae completely destroy the seeds. Infested cones dry out and harden. The insect is detected in cones by the presence of resin and fine frass near the entry holes.

The insect also attacks jack pine, but damage to this species is primarily located on the twigs. In May, the adult bores a tunnel at the ends of the previous year’s twigs. A plug of hardened resin can be seen at the base of the tunnel entry hole. Beginning in June, oviposition and the feeding of the young larvae in the tunnel cause new shoots to wilt and die.

The adult of the following generation has the same behaviour in the fall on both red pine and jack pine.

In September, the adult bores into current-year buds and shoots. Weakened shoots break off and fall to the ground, taking with them the adults, which overwinter in the shoots on the ground.

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
Egg
 
Larva
 
Pupa
 
Adult
 

Other information

The red pine cone beetle, Conophthorus resinosae Hopkins, and the jack pine tip beetle, Conophthorus banksianae McPherson, were long thought to be two separate species, the first being associated exclusively with red pine and the second exclusively with jack pine. Several studies over the last decade have suggested that these two beetles are actually the same species and should now be designated by the same name, i.e. the red pine cone beetle, Conophthorus resinosae Hopkins.

The insect is generally found throughout the range of red pine and jack pine. In Ontario, this beetle is considered the most destructive insect pest of red pine cones. In 1983, it caused severe damage to jack pine in western Quebec. Since then, there have been no reports of red pine cone beetle outbreaks in annual reports.

In the case of isolated trees or plantations, it is recommended that cones and shoots that have fallen to the ground be gathered and burned in order to reduce the population.

Canadian Forest Service Publications

Red pine cone beetle

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.
  • Xylophagous: Feeds on woody tissues (wood).
    • Borer: Bores into and feeds on the woody and non-woody portions of plants.

Main host(s)

Jack pine, red pine