Yosemite bark weevil

Pissodes schwarzi

The adult Yosemite bark weevil is rough-surfaced, mottled, reddish-brown to dark brown and 5 to 7 mm in length.

One this page:

• Description
• Host tree species
• Damage symptoms

Description

Yosemite bark weevils bore under the bark in the bole, root collar, and large roots of stressed or dying trees. They are commonly found in lodgepole pine affected by serious damaging agents, such as Comandra blister rust.

Overwintering adults primarily lay their eggs in May through July. The creamy white larvae feed throughout the summer, and overwinter under the bark in distinctive “chip cocoons”.

Host tree species

The Yosemite bark weevil primarily attacks young lodgepole pine, but has been found in other pines, spruces, and western larch.

Damage symptoms

The Yosemite bark weevil can attack and kill stressed trees including trees in drought environments.

Further reading

Read more about the Yosemite bark weevil in the Field Guide to Forest Damage in B.C. (PDF, 6.6MB)