Quebec, New Brunswick, Ontario, Western Canada
Damage, symptoms and biologyZale duplicata is a common innocuous solitary defoliator.
Mature larva to 35 mm long. Head, mottled brown or grey with prominent white marking at vertices. Body, elongate, rusty brown (most common) to dark grey. Middorsal white to greyish white Y marking on the posterior margin of each abdominal segment. Prominent pair of tubercles on dorsum of eighth abdominal segment. First two pairs of mid-abdominal prolegs reduced in size.
This species overwinters in the pupal stage. Adults emerge in May, larvae are present June to August and pupation occurs in August.
Life cycle (East 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.