Damage, symptoms and biologyThe filament bearer is a common solitary defoliator, occasionally causing noticeable defoliation. During outbreaks considerable mortality may occur in understory western hemlock.
Mature larva to 21 mm long. Unique caterpillar with two pairs of white tipped tentacles on the dorsum of the second and third abdominal segments. Head, mottled rusty brown. Body, rusty brown with prominent paired dorsal tubercles on the first and eighth abdominal segments.
This species overwinters in the egg stage. Larvae are present from June to July, pupation occurs in July or August, and adults emerge about two weeks later.
Life cycle (West of the Rockies)
Canadian Forest Service Publications
Diet and feeding behaviour
: Feeds on the leaves of plants.
- Free-living defoliator: Feeds on and moves about freely on foliage.