Scudder's Sulphur (Colias scudderi Reakirt)
Wing span: 1 1/2 - 2 inches (3.8 - 5.1 cm).
Identification: Upper surface of male lemon yellow; dark wide border cut by yellow veins. Females often white, with small black cell spot; border incomplete or lacking. Underside of both sexes dirty green.
Life history: Males patrol near willows for receptive females. Females lay eggs singly on young host plant leaves. Caterpillars eat leaves. Second-, third-, and fourth-stage caterpillars hibernate.
Flight: One flight from late June-August.
Caterpillar hosts: Willow shrubs in the willow family (Salicaceae).
Adult food: Flower nectar.
Habitat: Mountain meadows and willow bogs.
Range: Alaska south through Rocky Mountains to northern New Mexico.
