Papilio eurymedon
The swallowtails are the largest butterflies of the Pacific Northwest, with the tiger swallowtails attaining a wingspan of near 4 inches. The pale tiger swallowtail is the most common swallowtail in our area, and is commonly seen in backyards as it is over forest clearings. It favors nectaring at such flowers as teasel, milkweed, thistles, butterfly bush, mints, and lilacs. The larvae, seen beginning in August, commonly feed on willows, aspen or cottonwood, alder, and the orchard trees in the genera Prunus and Pyrus.
The large yellow wings have black stripes trailing from the leading edge, and the backs of the wings are trimmed with a thick band of black.
The range of the Western Tiger Swallowtail is basically the western half of the United States, from Wyoming, Colorado, and New Mexico on the east to southern British Columbia, south to southern California and Arizona.