Blackandwhite Sedge

Specimens from California determined as Carex albonigra are provisionally assigned here; these need further study because they differ from the typical Rocky Mountain forms.

Plants densely cespitose. Culms 10–30 cm, distally finely scabrous. Leaves 2.5–5 mm wide. Inflorescences: proximal bracts shorter than or exceeding inflorescences; spikes contiguous, overlapping, erect, distinct, short-pendunculate, short-oblong or elongate, 8–20 × 4–7 mm; lateral 1–3 spikes pistillate pedunculate, of similar length; terminal spike gynecandrous. Pistillate scales light to dark brown with hyaline margins, broadly lanceolate or ovate, equaling perigynia, midvein same color as body, inconspicuous, raised, prominent, short-mucronate. Perigynia ascending, chestnut, veinless, ovate, 3–3.5 × 2–2.5 mm, apex abruptly beaked, papillose; beak 0.3–0.4 mm, entire or shallowly bidentate, smooth. Achenes nearly filling body of perigynia. 2n = 52, 54.

Alta., B.C., N.W.T., Yukon; Alaska, Ariz., Calif., Colo., Idaho, Mont., N.Mex., Utah, Wash., Wyo.

Fruiting Jun–Aug.

Alpine meadows, fellfields; 300–3900m.

Carex albonigra is a species of sedge known by the common name black and white sedge. It is native to western North America from Alaska and most of western Canada to California to New Mexico, where it grows in mainly dry, rocky high mountain habitat such as talus. This sedge forms a dense clump 10 to 30 centimeters in height with narrow gray-green leaves. The inflorescence is a headlike cluster of overlapping spikes. The fruit is coated in a sac called a perigynium which is dark purple to chestnut brown and often tipped with white.