9.03 SCHIZACHNE Hack.
Jacques Cayouette, Stephen J. Darbyshire
Plants perennial; loosely cespitose. Culms 30–110 cm, glabrous, often decumbent at the base; nodes glabrous, becoming dark. Sheaths closed almost to the top; ligules membranous, margins often united in front; blades folded or loosely involute, glabrous or pilose. Inflorescences panicles or racemes, with 4–20 spikelets; branches straight and appressed to lax and drooping. Spikelets slightly laterally compressed, with 3–6 florets; disarticulation above the glumes and beneath the florets. Glumes exceeded by the lowest lemma in each spikelet, chartaceous, often anthocyanic below, the upper 1/3 hyaline; calluses rounded, with hairs; lemmas chartaceous, slightly scabrous, 7–9-veined, veins parallel, conspicuous, apices scarious, bifid, awned from below the teeth, awns 8–15 mm, divergent or slightly geniculate; paleas shorter than the lemmas, 2-veined, veins ciliate, keeled; lodicules truncate; anthers 3; ovaries glabrous. Caryopses 3.2–3.8 mm, smooth, shiny, falling free of the lemma and palea. x = 10. Name from the Greek schizo, ‘split’, and achne, ‘chaff’, alluding to the split (bifid) lemma.
Schizachne is a monospecific genus that extends across North America in boreal regions and southwards in the montane areas, as well as from the Ural Mountains of Russia to Kamchatka and Japan.
SELECTED REFERENCES Koyama, T. and S. Kawano. 1964. Critical taxa of grasses with North American and eastern Asiatic distribution. Canad. J. Bot. 42:859–884; McNeill, J. and W.G. Dore. 1976. Taxonomic and nomenclatural notes on Ontario grasses. Naturaliste Canad. 103:553–567; Tsvelev, N.N. 1976. Zlaki SSSR. Nauka, Leningrad [St. Petersburg], Russia. 788 pp.
1. Schizachne purpurascens (Torr.) Swallen
False Melic, Schizachné Pourpré
Culms (30)50–80(110) cm, sometimes slightly decumbent at the base, otherwise erect. Ligules 0.5–1.5 mm; blades 2–4(5) mm wide, glabrous or adaxial surfaces pilose. Panicles 7–13(17) cm, open or closed, often reduced to racemes in depauperate plants. Spikelets 11.5–17 mm. Glumes glabrous, acute; lower glumes 4.2–6.2 mm, faintly (1)3–5-veined; upper glumes 6–9 mm, faintly (3)5-veined; lemmas 8–10.5(12) mm; awns 8–15 mm, as long as or longer than the lemma bodies, somewhat twisted and divergent or slightly geniculate; anthers 1.4–2 mm. 2n = 20.
In North America, Schizachne purpurascens grows in moist to mesic woods, from south of the tree line in Alaska and northern Canada through the Rocky Mountains to New Mexico in the west, and to Kentucky and Maryland in the east.