Roots without elongate central axis; fascicles 2-8, ± horizontal. Stems (30-)60-100(-150) cm. Leaves all cauline at anthesis; distalmost petioles less than 5 mm. Leaf blade not distinctly 3-parted; ultimate lobes of midcauline leaf blades 12-25, width 0.5-1.5 mm. Flowers: sepals various shades of blue or purple, rarely white. 2 n = 16, 32.

Flowering late winter-early summer. Prairies and forest openings; 50-700 m; Ala., Ark., Fla., Ga., Ill., Iowa, Kans., Miss., Mo., N.C., Okla., S.C.

Delphinium carolinianum subsp. carolinianum occasionally hybridizes with D . treleasei.