Stems 90-150 cm; base usually green, glabrous. Leaves cauline, 17-30 at anthesis; petiole 0.2-8 cm. Leaf blade cuneate to semicircular, 2-5 × 3-12 cm, nearly glabrous; ultimate lobes 3-21, width 1-8 mm. Inflorescences 25-80-flowered, dense; pedicel 0.5-2 cm, glandular-pubescent; bracteoles 1-4 mm from flowers, green, lanceolate, 3.5-6 mm, glandular-pubescent. Flowers: sepals yellowish green, nearly glabrous, lateral sepals forward pointing, 7-9 × 3-4 mm, spurs decurved, 30-45° below horizontal, often hooked apically, 8-11 mm; lower petal blades ± covering stamens, 4-6 mm, clefts 0.5-1.5 mm; hairs centered, mostly near junction of blade and claw, yellow. Fruits 8-11 mm, 2.5-3 times longer than wide, puberulent. Seeds ± wing-margined; seed coat cells with surfaces ± roughened.

Flowering summer. Wet meadows and streamsides in coniferous forest, heavy clay soils; of conservation concern; 500-1000 m; Wash.

Delphinium viridescens is local in mountains southwest of Wenatchee, Washington.