Abies grandis
The larvae feed on the foliage of various coniferous trees, including "Tsuga heterophylla", "Tsuga mertensiana", "Pseudotsuga", "Thuja plicata", "Abies amabilis", "Abies grandis", "Abies lasiocarpa" and "Picea engelmannii". They have a rusty brown to gray body with white dorsal patches and a light tan head with reddish-brown mottling. They reach a length of up to 20 mm. When at rest, the larva resembles a bird dropping. Larvae can be found from May to July. The species overwinters as an egg. Pupation takes place in a cocoon on a twig in August.