Bull. Torrey Bot. Club 28: 578. 1901.
Herbs, perennial, cespitose, ashy to bronze olive when dry, to 2.5 dm, not glaucous. Stems branched, with 1–2 nodes, 1–2.8 mm wide, scabrous at least apically, margins entire to denticulate apically, similar in color and texture to stem body; first internode 5.3–12.5 cm, equaling or shorter than leaves; distalmost node with 2–3 branches. Leaf-blades usually scabrous, bases not persistent in fibrous tufts. Inflorescences borne singly; spathes green, obviously wider than supporting branch, scabrous, keels denticulate or entire; outer 18.6–26.5 mm, 2.5–5.5 mm longer than inner, tapering evenly towards apex, margins basally connate 2.5–3.9 mm; inner with keel evenly curved or straight, hyaline margins 0.2–0.4 mm wide, apex acuminate to acute, ending 0–1.5 mm proximal to green apex. Flowers: tepals bluish violet to purplish blue, bases yellow; outer tepals 8.3–10.5 mm, apex rounded to truncate or emarginate, aristate; filaments connate ± entirely, slightly stipitate-glandular basally; ovary similar in color to foliage. Capsules tan to light-brown, ± globose, 3–5 mm; pedicel ascending to spreading. Seeds globose to obconic, lacking obvious depression, rugulose. 2n = 32.
Phenology: Flowering spring.
Habitat: Prairies, open woods
Elevation: 20–200 m
Ala., Ark., Kans., Nebr., Okla., Tex.
Sisyrinchium pruinosum can be expected also in Louisiana, Missouri, and Mississippi.
"obviously wider" is not a number.