1. Scleria ciliata Michx. (hairy nut grass)

Pl. 86 c–e; Map 326

S. ciliata var. elliottii (Britton) Fernald

Plants perennial with knotty rhizomes. Aerial stems usually appearing clustered, 20–70 cm long, erect to ascending, glabrous or hairy. Leaf sheaths usually not winged but often roughened along the angles, hairy, green and often somewhat purplish tinged, the convex tip opposite the leaf blade 1–2 mm long, broadly rounded, hairy. Leaf blades 1–35 cm long, 1–7 mm wide, glabrous or hairy, especially along the margins and main veins. Inflorescences few to several clusters of spikelets, these arranged in 1–3 headlike masses. Bracts erect to ascending, 0.8–11 cm long. Spikelets 4.0–6.5 mm long, the scales green to purplish brown. Fruits with the main body 1.8–3.0 mm long at maturity, broadly ovate to circular in outline, the tip usually with a minute point, the surface irregularly warty and sometimes also with short ridges, shiny, white or rarely tinged with gray, the basal disk irregularly 3-angled, with 3 tubercles, these often irregularly and deeply 2-lobed, thus appearing as 4–6 tubercles. June–October.

Scattered in the Ozark and Ozark Border Divisions (southeastern U.S. west to Texas; Caribbean Islands). Glades, upland prairies, savannas, openings of dry upland forests, mostly (but not exclusively) on acidic substrates.

Some botanists recognize several varieties within this species, based upon differences in degree of pubescence, leaf width, and general robustness of the plants. Variation in these characters does not correlate well in Missouri material, and the number of intermediates makes it unwise to provide formal taxonomic recognition for the various races of S. ciliata in the state. A greater problem exists with the separation of S. ciliata from the closely related S. pauciflora. Some botanists believe that these taxa should not be recognized as separate species, although nearly all floristic manuals regard them as distinct. In general, specimens can be determined readily to one or the other of these two taxa, but some plants have the 3 tubercles at the base of the fruit deeply 2-lobed and are difficult to categorize. For such plants, the fruit sizes indicated in the key to species are often helpful in separating the two.