Burke's Larkspur: Delphinium xburkei -
Blue Mt. Larkspur, Dwarf Larkspur, Slim Larkspur: Delphinium depauperatum (Synonyms: Delphinium cyanoreios, Delphinium diversifolium, Delphinium diversifolium ssp. harneyense, Delphinium diversifolium var. harneyense) - Plants less than 60 cm high. Stem leaves mostly near the base and the lowest green at flowering time. Lower petals with hairs in central tufts. Inflorescence usually glandular-puberulent and narrow throughout. Plants of riparian areas or areas moist early in the season.
Meadow Larkspur, Two-spike Larkspur: Delphinium distichum (Synonyms: Delphinium burkei, Delphinium strictum var. distichiflorum) - Plants less than 60 cm high. Stem leaves numerous crowded, and of different shapes along the stems. The lower leaves with wider lobes, the upper with narrow lobes. Racemes narrow throughout with pedicels no longer than the spurs. Plants of wet meadows and other sites wet early in the season.
Olympic Larkspur, Olympic Mt. Larkspur, Rockslide Larkspur: Delphinium glareosum (Synonyms: Delphinium basalticum, Delphinium caprorum, Delphinium glareosum ssp. caprorum, Delphinium glareosum ssp. glareosum, Delphinium glareosum var. caprorum) -
Duncecap Larkspur, Pale Larkspur, Mountain Larkspur, Sierra Larkspur, Western Larkspur: Delphinium glaucum (Synonyms: Delphinium occidentale, Delphinium occidentale ssp. occidentale, Delphinium scopulorum, Delphinium scopulorum var. glaucum, Delphinium scopulorum ssp. occidentale, Delphinium splendens) -
Cliff Larkspur, Menzies' Larkspur: Delphinium menziesii (Synonyms: Delphinium menziesii ssp. menziesii, Delphinium menziesii ssp. pyramidale, Delphinium menziesii var. menziesii, Delphinium menziesii var. pyramidale) -
Kittitas Larkspur: Delphinium multiplex (Synonym: Delphinium cyanoreios f. multiplex) - Plants 45-100 cm high. The sepals are up to 15 cm long with rounded to abruptly acute tips. The leaves are of several types with the lower ones dissected into oblong, obtuse or rounded segments while the uper leaves have much narrower segments. Plants of the Wenatchee Mts of northern Kittitas county and southern Chelan county of Washington.
Thin-petal Larkspur, Two-lobe Larkspur, Upland Larkspur: Delphinium nuttallianum (Synonyms: Delphinium bicolor, Delphinium decorum ssp. tracyi, Delphinium lineapetalum, Delphinium nelsonii, Delphinium nuttallianum var. fulvum, Delphinium nuttallianum var. levicaule, Delphinium nuttallianum var. lineapetalum, Delphinium nuttallianum var. nuttallianum, Delphinium pauciflorum, Delphinium sonnei) - Plants mostly 10-40 cm high. Flowers with 5 sepals of roughly equal length, of a dark blue color. The inner petals are smaller, with the lower pair whitish with blue veins and deeply notched at the tips. Leaves simple, palmate, and deeply lobed.
Nuttall's Larkspur, Upland Larkspur: Delphinium nuttallii (Synonyms: Delphinium nuttallii ssp. nuttallii) -
Willamette Valley Larkspur: Delphinium oreganum - Generally a species of the lowlands of the Willamette Valley, some may be found high into the west slope Cascades of Marion County, OR.
Cow Poison, Poison Larkspur: Delphinium trolliifolium -
Wenatchee Larkspur: Delphinium viridescens -
Yellow-white Larkspur: Delphinium xantholeucum -