Panicum acuminatum

HABIT Perennial. Culms 15–40 cm long. Culm-internodes distally pubescent. Culm-nodes bearded. Lateral branches sparse, or ample; arising from lower culm. Leaves heterophyllous with a basal winter rosette. Leaf-sheaths glabrous on surface, or pilose; with tubercle-based hairs. Ligule a fringe of hairs; 3–4 mm long. Leaf-blades 4–8 cm long; 5–12 mm wide. Leaf-blade surface pubescent; hairy abaxially. Leaf-blade margins tuberculate-ciliate.

INFLORESCENCE Inflorescence a panicle.

Panicle open; oblong; 3–9 cm long.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic, or oblong, or obovate; dorsally compressed; acute; 1.5–2 mm long; falling entire.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 0.25–0.33 length of spikelet; membranous; without keels; 1 -veined. Lower glume lateral veins absent. Lower glume apex obtuse. Upper glume ovate; 1 length of spikelet; membranous; without keels; 7–9 -veined. Upper glume surface pubescent. Upper glume apex obtuse.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret similar to upper glume; ovate; 1 length of spikelet; membranous; 7–9 -veined; pubescent; obtuse. Palea of lower sterile floret 0.25 length of lemma. Fertile lemma ovate; dorsally compressed; 1.5–2 mm long; indurate; without keel. Lemma margins involute. Lemma apex obtuse. Palea involute; indurate.

DISTRIBUTION Europe: eastern. Asia-temperate: Caucasus. Australasia: New Zealand. North America: western Canada, eastern Canada, northwest USA, north-central USA, northeast USA, southwest USA, south-central USA, southeast USA, and Mexico. South America: Mesoamericana, Caribbean, northern South America, and western South America.

NOTES Paniceae. Fl Pac NW 1994.

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