Scientific Name
Carex multicostata Mack. (Synonyms: Carex pachycarpa)
Common Name(s)
Manyrib sedge
Tribe / Family Name
Cyperaceae
Flowering Period
July to August
Symbol
CAMU6
Description
Manyrib sedge is a native cool-season perennial bunched grass-like plant. Culms range from 15–90 cm in height and exceed the leaves. Inflorescences are up to 3 cm long with 3–10 sessile spikes that are densely crowded together into narrow to globose-ovoid, pale, shaggy heads; spikes are gynaecandrous. Bracts are short and inconspicuous. Perigynia are 3.5–6.3 mm long, up to 2.5 mm wide, narrowly to broadly ovate, plano-convex, obscurely or conspicuously 10 or more nerved on both surfaces, cream or tan with greenish winged margins, and surrulate to below the middle; beaks are slender or more or less flattened, winged nearly to the tips, entire or bidentate, and dark colored at the tips. Pistillate scales are up to 4.8 mm long, ovate, longer and narrower than perigynia, and gold or light brown with a paler 3-nerved midstripe and broad hyaline margins. Stigmas 2. Fruits are achenes, lenticular, and yellow or light brown. Leaves are 8–25 cm long, up to 6 mm wide, 3–4 per culm, flat or nearly so, and more or less crowded towards the base. Sheaths are white-hyaline adaxially and truncate at mouth.
General Info
Manyrib sedge can be found in moist or dry meadows, streambanks, and in montane and subalpine sites.
Similar Species
Manyrib sedge may look similar to other sedge (Carex) species. Careful attention should be focused on its large, dense, pale, shaggy inflorescence head and long perigynia with many nerves on each surface when distinguishing from other grass-like species.
Picture of growth habit.
Inflorescences have 3-10 sessile spikes that are dense, pale, shaggy, and head-like.
Illustration of perigynium. Le Hall, 2018.