Sphenopholis pensylvanica

HABIT Perennial; caespitose. Culms 30–120 cm long. Leaf-sheaths glabrous on surface, or pubescent. Ligule an eciliate membrane. Leaf-blades 5–20 cm long; 1–7 mm wide. Leaf-blade surface glabrous, or pubescent.

INFLORESCENCE Inflorescence a panicle.

Panicle open; oblong; effuse; 7–35 cm long. Primary panicle branches appressed.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels linear.

FERTILE SPIKELETS Spikelets comprising 2–3 fertile florets; with a barren rhachilla extension. Spikelets obovate; laterally compressed; 5–9.5 mm long; falling entire. Rhachilla internodes 1–2.1 mm long; pubescent; with 0.5–0.8 mm long hairs.

GLUMES Glumes dissimilar; with lower narrower than upper; shorter than spikelet; gaping. Lower glume lanceolate; 3.5–5.5 mm long; 0.9 length of upper glume; membranous; 1-keeled; 1–3 -veined. Lower glume primary vein scaberulous. Lower glume apex acute; muticous, or mucronate. Upper glume obovate; 3.8–6.2 mm long; 0.9–1 length of adjacent fertile lemma; membranous; 1-keeled; 3–5 -veined. Upper glume primary vein scaberulous. Upper glume apex acute; muticous, or mucronate.

FLORETS Fertile florets all alike, or with the lowest dissimilar (smooth, mucronate). Fertile lemma ovate; 3.9–7.2 mm long; membranous; without keel; 5 -veined. Lemma surface scabrous; rough generally. Lemma apex acute; awned; 1 -awned. Principal lemma awn subapical; curved; 3.5–7 mm long overall. Palea gaping; 0.8 length of lemma. Palea keels scaberulous. Rhachilla extension 0.75 length of fertile floret.

FLOWER Ovary glabrous.

FRUIT Caryopsis with adherent pericarp; oblong; glabrous. Endosperm liquid.

DISTRIBUTION North America: northeast USA and southeast USA.

NOTES Aveneae. Erdman.

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