Flora of North America species comparison

often ascending or spreading, 4-angled or sometimes terete, sometimes sulcate, 1–7 cm × 0.2–0.3 mm, soft to firm.

2–40 cm × 0.5–1.5(–2) mm.

sheaths stramineous, distal sheaths often splitting abaxially, slightly inflated distally, oblique, apex acute.

apex of distal leaf sheath obtuse to acute, tooth to 0.3 mm.

ovoid, 1.5–4 × 0.8–2 mm, apex acute;

floral scales 4–15, 8 per mm of rachilla, colorless or reddish brown, midrib region green, ovate-lanceolate, not folded lengthwise, 1–1.5 × 0.5–0.7 mm, mibrib obscure to somewhat keeled, apex narrowly acute to acuminate, slightly recurved.

lanceoloid to subcylindric or ovoid, 5–10(–20) × 2–3(–4) mm, apex acute (to rounded);

proximal scale empty, encircling ca. 2/3 of culm;

floral scales 25–100(–200), 8–12 per mm of rachilla, orangebrown to stramineous, 2(–2.5) × 1–1.3 mm, midribs mostly keeled, ovate, apex narrowly rounded to subacute.

perianth bristles absent;

anthers 0.3–0.5 mm.

perianth bristles present or often absent, 5–8, brown, stout, rudimentary to slightly exceeding tubercle;

stamens (2–)3;

anthers brown to yellow, 0.3–0.7(–1) mm;

styles 2–3-fid.

with angles and longitudinal ridges ca. 6–10, rather prominent, broadly ovoid, less than 2 times longer then wide, (0.55–)0.65–0.75 × 0.3–0.4 mm, apex blunt, trabeculae distinct, 20–30.

0.9–1.1(–1.5) × 0.7–1.1 mm.

grayish, mostly appressed, pyramidal, often depressed, 0.1–0.2 × 0.1–0.25 mm.

depressed, subdeltoid, 0.1–0.3(–0.4) × 0.6–0.9(–1) mm, 1/10–2/5 as high as wide, 1/4 or less as high as achene, 9/10 as wide as achene, very rarely 2/5 as high as achene (in E. engelmannii var. robusta).

= 10.