Northern Prairie Wildlife Research Center
Wingspan 3.5 cm. Forewing is a uniform pale gray with a narrow, sharply dentate median line. This geometrid is common, particularly west of the Cascade Mountains. Moths fly in midsummer. Caterpillars are generalist feeders on the foliage of flowering trees and shrubs such as buckbrush (Rhamnus purshiana), ocean spray (Holodiscus discolor), elderberry (Sambucus), and snowberry (Symphoricarpos albus).
Similar species: Melanolophia imitata has less gray on the forewing, moths fly in early spring.