Piptochaetium avenaceum

HABIT Perennial; caespitose. Culms erect; slender; 35–75 cm long. Culm-internodes distally glabrous. Culm-nodes glabrous. Leaf-sheaths glabrous on surface, or pubescent. Leaf-sheath oral hairs lacking. Ligule an eciliate membrane; 1.5–4.5 mm long. Leaf-blades filiform; flat, or involute; 10–30 cm long; 1 mm wide.

INFLORESCENCE Inflorescence a panicle.

Panicle open; elliptic; 7–25 cm long; bearing few spikelets. Primary panicle branches spreading, or drooping; 2–4 cm long; bearing 1–2 fertile spikelets on each lower branch.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 10–15 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus elongated; 2 mm long; pubescent; acute.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 10–15 mm long; 1 length of upper glume; hyaline; without keels; 3–5 -veined. Lower glume apex attenuate. Upper glume lanceolate; 10–15 mm long; 1.2–1.5 length of adjacent fertile lemma; hyaline; without keels; 5 -veined. Upper glume apex attenuate.

FLORETS Fertile lemma linear; subterete; 8–10 mm long; coriaceous; dark brown; without keel; 5 -veined. Lemma surface scaberulous; rough above; glabrous. Lemma margins convolute; covering most of palea. Lemma apex surmounted by a ring of hairs; awned; 1 -awned. Principal lemma awn geniculate, or bigeniculate; 35–70 mm long overall; with twisted column. Column of lemma awn glabrous. Palea without keels.

FLOWER Anthers 3. Stigmas 2. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp. Hilum linear.

DISTRIBUTION North America: northeast USA, south-central USA, southeast USA, and Mexico.

NOTES Stipeae. Gr Texas 1994.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.