T: California, San Bernardino Co., Miller Canyon, East Fork of West Fork Mojave R., San Bernardino Mtns, 22 Sep 2001, P.F.Zika 16587; holo: WTU; iso: CAS, ENCB, GH, MEXU, MICH, MO, NY, OSC, PRA, RSA, UC, US.
Plants 40–120 (–150) cm tall; stems erect in flower, finally lax in fruit, 1.2–3 (–3.5) mm in diam., faintly 11–35-striate with subepidermal sclerenchyma strands opposite the larger vascular bundles; upper part of stem shiny and smooth when fresh. Upper cataphylls (5–) 8.8–15.6 (–17.2) cm long, abaxially mostly brown or rufescent, chartaceous at base where sometimes lustrous; upper half green, stramineous brown when dry or overmature, dull, surface scabridulous to smooth; margins broadly scarious; not strongly overlapping at the apex; apex mostly asymmetrical, rarely truncate, with strongly convergent sometimes nearly parallel veins. Lower bract 7.3–19.2 (–24.5) cm long, 1/6–2/5 the length of the culm; basal sheath medium to narrow. Inflorescence usually lax, (1–) 3.4–6.5 (–8.5) × (1.2–) 1.4–6.0 (–7.5) cm; longest peduncle 1.1–4.7 (–6.0) cm long; middle bracts mostly with medium-sized membranous margin, 2.5–5.6 (1.4–7.3) mm long with an apical spine 1.3–4.5 (0.7–5.5) mm long. Tepals lanceolate, mostly acute, apiculate; outer tepals 1.9–3.0 (–3.6) mm long, with a narrow green midrib bordered by greenish or pale brown bands and narrow hyaline margins, spreading from fruit, acuminate; inner tepals subequal or shorter, 1.7–3 mm long. Capsule mostly trigonous-obovoid, sometimes elliptical, mostly subequalling or shorter than perianth, olive-brown; apex mostly apiculate, sometimes darker.