Panicum macrospermum

HABIT Perennial. Rootstock evident. Culms erect; 50–80 cm long; 4–6 -noded. Leaf-sheaths hispid; outer margin hairy. Ligule a ciliolate membrane. Leaf-blade base cordate. Leaf-blades lanceolate; 7–15 cm long; 10–15 mm wide. Leaf-blade surface hispid; hairy on both sides.

INFLORESCENCE Inflorescence a panicle. Peduncle hispid above.

Panicle open; ovate; effuse; 13–18 cm long; with spikelets clustered towards branch tips. Panicle axis hispid. Panicle branches capillary; hispid.

Spikelets appressed; solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 3.8–4.2 mm long; falling entire.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 2–3 mm long; 0.5–0.7 length of spikelet; membranous; without keels. Lower glume apex acute. Upper glume elliptic; 1 length of spikelet; membranous; without keels. Upper glume surface puberulous. Upper glume apex obtuse.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret similar to upper glume; elliptic; 1 length of spikelet; membranous; puberulous. Fertile lemma elliptic; dorsally compressed; 3.8–4.2 mm long; indurate; without keel. Lemma margins involute. Palea involute; indurate.

DISTRIBUTION North America: Mexico.

NOTES Paniceae. Gould 2004.

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