Orthocarpus luteus is an upper elevation herb with bright yellow flowers partially obscured by the green calyx. The stems are purple. The leaves are linear to lanceolate. Orthocarpus luteus is found in meadows and openings in the Ponderosa forest.
Finely glandular-hairy; stems 1-3 dm, simple or occasionally branched; lvs numerous, linear or rarely trifid, 1-2 cm; bracteal lvs trifid or rarely linear; fls bright yellow, 9-12 mm; 2n=28. Dry prairies and plains; Minn. to Alta. and B.C., s. to Nebr., N.M., and Calif. July-Sept.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.