Colias philodice (or eriphyle)
Size: 2.0 - 2.5 inches wingspan
Key ID features: Pale yellow above with black or dark gray border, lime-green or yellow below. Some females lack yellow pigment and are white with black border above. Forewing below has blackish submarginal spots, hindwing below has submarginal row of brown "eurytheme" spots. Discal spot usually enclosed by double red ring with satellite spot.
Similar species: Male Orange Sulphur is shaded with orange. White females very difficult to separate, but in Orange Sulphur they tend to have a bolder dark border on the hindwing above. Western Sulphur has single red ring enclosing the discal spot.
Host plant: Many species in the pea family.
Habitat: Many types of habitats, both disturbed and undisturbed, but usually not along roads in deep forest.
Range: All of eastern Oregon.
Season: early May to mid-October
Conservation Status: Secure