Delphinium gracilentum

Stems (15-)30-50(-80) cm; base reddish, nearly glabrous. Leaves mostly cauline; basal leaves 0-3 at anthesis; cauline leaves 2-5 at anthesis; petiole 3-15 cm. Leaf blade round to pentagonal, 1.5-4 × 3-7 cm, nearly glabrous; ultimate lobes 3-7, distinctly wedge-shaped, usually 5 or fewer extending 3/5 distance to petiole, width 5-20 mm (basal), 1-15 mm (cauline), widest in distal 1/2. Inflorescences 5-20(-38)-flowered; pedicel spreading from rachis at nearly 90° 1-3(-4) cm, glabrous or glandular-pubescent; bracteoles (7-)11-19 mm from flowers, blue or green, linear, 2-5 mm, puberulent to glabrous. Flowers: sepals dark bluish purple to pink or white, usually retaining color upon drying, glabrous, lateral sepals reflexed, 6-10(-13) × 3-6 mm, spurs often curved upward, within 30° above or below horizontal, 8-12(-14) mm; lower petal blades elevated, exposing stamens, 3-5 mm, clefts 1-3 mm; hairs almost exclusively near base of cleft, centered or mostly on inner lobes, usually yellow. Fruits 8-16 mm, 3-3.5 times longer than wide, glabrous to glandular-puberulent. Seeds unwinged; seed coats ± pitted, cell surfaces roughened.

Flowering spring-early summer. Open coniferous forest; 150-2700 m; Calif.

Delphinium gracilentum hybridizes with D . patens subsp. patens in the northern Sierra Nevada foothills and is very similar to that species, making hybrids difficult to discern. While D . gracilentum and D . patens are easily distinguished in most of their ranges, morphologic distinctions between the two taxa are blurred in the northern Sierra Nevada foothills region, particularly in Butte County, California. Coniferous woods are preferred by D . gracilentum ; D . patens subspp. patens and hepaticoideum are more often found in broadleaf woods. The former species has more widely spreading pedicels than the latter, and D . gracilentum usually has wider leaf lobes than D . patens subsp. patens . In the southern Sierra Nevada, D . gracilentum may come in contact with D . patens subsp. montanum . Though hybrids are not common, some gene flow has apparently occurred.