Eldorado Larkspur

Although Delphinium hansenii has often been confused with D . hesperium , seeds will instantly allow identification. Seeds of Delphinium hansenii are, as far as known, unique, bearing numerous, elongate, prismlike raised structures (extensions of single cells or small groups of cells) over the entire seed coat. If seeds are absent, larger flowers, more open inflorescences (except in D . hesperium subsp. cuyamacae ), and general absence of pubescence of long hairs in D . hesperium are apparent upon comparison of the two species. Separating D . hansenii from D . variegatum may also be difficult. Again, seeds leave no doubt. In addition, smaller flowers and greater number of flowers per plant of D . hansenii should serve to distinguish D . hansenii from D . variegatum . White-flowered D . hansenii has been confused with D . gypsophilum and with D . hesperium subsp. pallescens . Other than seeds, pubescence of long hairs and smaller flowers present in D . hansenii and absent in the others will distinguish them.

Stems (25-)40-80(-180) cm; base usually reddish, pubescent. Leaves cauline and basal; basal leaves 0-5 at anthesis; cauline leaves 2-8 at anthesis; petiole 0.5-8 cm, petioles of proximal leaves long-pubescent. Leaf blade pentagonal, 1.5-5 × 2.5-8 cm, long-pubescent, especially abaxially; ultimate lobes 0-18, width 4-20 mm (basal), 2-9 mm (cauline). Inflorescences (9-)15-40(-160)-flowered, dense to open; pedicel 0.3-2.5(-6) cm, puberulent; bracteoles 1-5(-8) mm from flowers, green, sometimes white-margined, linear-lanceolate, 2-6(-8) mm, puberulent. Flowers: sepals violet to white, ± puberulent, lateral sepals spreading to forward pointing, 7-10(-13) × 3-6(-8) mm, spurs gently upcurved, ascending 0-30° above horizontal, (6-)9-13(-16) mm; lower petal blades elevated, ± exposing stamens, 3-7 mm, cleft 1-2(-4) mm; hairs centered, densest on inner lobes near base of cleft, white. Fruits 8-20 mm, 2.2-4 times longer than wide, glabrous. Seeds echinate, appearing fuzzy to naked eye; seed coat cells with margins straight, surfaces sparsely pustulate.

Delphinium hesperium A. Gray var. hansenii Greene, Fl. Francisc. 3: 304. 1892

Delphinium hansenii is a species of larkspur known by the common names Eldorado larkspur and Hansen's delphinium. It is endemic to California, where it grows in mountains, valleys, and desert from the southern Cascade Range to the Mojave Desert. This wildflower usually grows between one half and one meter in height, although it can grow much taller. The deeply lobed leaves are hairy, especially on the undersides. The inflorescence has usually over 25 flowers grouped close together at the top of the stem and held on long pedicels. The flowers are white to light blue or light pink, or bicolored, and vary in size. The inner petals may be quite hairy.