Pontia occidentalis (Reakirt, 1866)
Status: Uncommon resident
NENHP Ranking: S2 Tier 2
Range: This species is a resident from much of Alaska east through Ontario, and south through Colorado, Utah, Nevada and northern California. In Nebraska it has been found in the panhandle and Dundy County.
Larval Hostplant(s): Various members of the Crucifer family are listed, of which the following occur in Nebraska: Mustards (Arabis drummondi, A. glabra, Brassica nigra, Chorispora tennilla, Sisymbrium altissimum), Flixweed (Descurainia sophia), and varities of Peppergrasses (Lepidium virginicum and L. densiflorum).
Broods/Flight Times: Up to three broods from mid-May through August.
Overwintering: As pupae.
Habitat: The Western White is most often encountered on rocky or short grass prairie hillsides, although it has also been found in “urban” areas.
Avg. Wingspan: 1 1/2 – 2 1/8 inches
Found at: Gilbert-Baker SWMA
Similar Species: Spring and Checkered Whites