Rhizomes short, stocky. Culms cespitose, 8--40 cm x1 mm, base thickened, glabrous. Leaves: basal leaves to 13 cm; cauline leaves 1--3, mostly less than 5 cm x 5--10 mm, apex involute, glabrous. Inflorescences compact, irregular in shape; glomerules 6--10, sessile; branches few or none; proximal inflorescence bract conspicuous, leaflike, lanceolate, equal to or exceeding inflorescences; bracteoles clear, 1/2 tepal length. Flowers: tepals shining brown, with thin clear margins, 1.5--2 mm; outer and inner whorls nearly equal, (outer whorl slightly keeled); anthers longer than filaments; stigmas much longer than styles. Capsules deep purplish brown at maturity, globose (apex rounded), ± equaling tepals, apex rounded. Seeds brown, cylindric, 1.3 mm; caruncle absent.

Flowering and fruiting summer. Subalpine and alpine bogs; 3200--3700 m; Colo.

The rhizomes of Luzula subcapitata are stocky, and the culms have thickened, glabrous bases. The species has 1--3 cauline leaves, which are glabrous with narrow inrolled involute or revolute-- apices. The flowers are characterized by stigmas that are much longer than the styles.