Deyeuxia porteri

HABIT Perennial. Rhizomes elongated. Culms erect; 60–120 cm long; 2–4 -noded. Leaf-sheaths smooth; glabrous on surface. Leaf-sheath oral hairs pubescent. Ligule an eciliate membrane; 2–4 mm long. Leaf-blades spreading; 4–8 mm wide. Leaf-blade surface scaberulous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; linear; equilateral, or nodding; 10–15 cm long. Primary panicle branches appressed, or ascending; 2–5 cm long. Panicle axis scabrous. Panicle branches scabrous.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; laterally compressed; 4–6 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus bearded. Floret callus hairs 0.5 length of lemma.

GLUMES Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume surface asperulous. Lower glume apex acute. Upper glume lanceolate; 4–6 mm long; 1.1 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume surface asperulous. Upper glume apex acute.

FLORETS Fertile lemma lanceolate; 3.5–5.5 mm long; membranous; without keel; 5 -veined. Lemma apex dentate; 4 -fid; awned; 1 -awned. Principal lemma awn dorsal; arising 0.2 way up back of lemma; geniculate; 3–5 mm long overall; not or scarcely exserted from spikelet; with a straight or slightly twisted column. Palea 1 length of lemma. Rhachilla extension pilose; with 3 mm long hairs.

FLOWER Lodicules 2. Anthers 3. Stigmas 2.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform. Disseminule comprising a floret.

DISTRIBUTION North America: northeast USA and southeast USA.

NOTES Aveneae. N Amer Fl 1994.

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