Northern Prairie Wildlife Research Center
Wingspan 4.6 cm. Forewing is variable red-brown to green-gray with a straight, white postmedian line. This noctuid is common and widely distributed in western North America, often abundant in ponderosa pine forests. Moths fly in fall. Caterpillars bore in stems of grasses and herbs.
Similar species: some species of Amphipoea (Noctuidae) are similar in appearance but smaller with caterpillars that bore into and feed on grass rhizomes and roots; Amphipoea americana forewing is orange to red with orange discal spots, abundant in wet coastal forests; Amphipoea lunata forewing is red with narrow reniform spots, occurs in dry forests of California and southwest Oregon; Amphipoea senilis forewing is pale yellow or pink, abundant in dry, open ponderosa pine forests east of the Cascade Mountains; Amphipoea keiferi forewing is dark brown with pale discal spots, hindwing black, abundant in ponderosa pine forests east of the Cascade Mountains.