Stipa constricta

HABIT Perennial. Culms decumbent; 80 cm long; 4–6 -noded. Lateral branches sparse; arising from lower culm. Leaf-sheaths glabrous on surface. Ligule an eciliate membrane; 2–3 mm long. Leaf-blades involute; 5–15 cm long; 1–2 mm wide. Leaf-blade surface glabrous. Leaf-blade apex hardened.

INFLORESCENCE Inflorescence a panicle.

Panicle open; linear; 10–20 cm long. Primary panicle branches ascending.

Spikelets solitary. Fertile spikelets pedicelled. Pedicels pubescent.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 8 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; 1 mm long; pubescent (white); unequally 2-toothed.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume lanceolate; 1 length of upper glume; membranous; without keels; 3 -veined. Lower glume apex acuminate. Upper glume lanceolate; 25–40 mm long; membranous; without keels; 3 -veined. Upper glume apex acuminate.

FLORETS Fertile lemma linear; subterete; 14–16 mm long; membranous; dark brown; without keel; 5 -veined. Lemma surface pubescent. Lemma margins flat; covering most of palea. Lemma hairs white. Lemma apex with a short cylindrical neck and surmounted by a ring of hairs; with this appendage 1.2–1.4 mm long; awned; 1 -awned. Principal lemma awn bigeniculate; 20–25 mm long overall; with twisted column. Palea 0.6 length of lemma; 2 -veined; without keels.

FLOWER Lodicules 3. Anthers 3; anther tip smooth. Stigmas 2. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp. Hilum linear.

DISTRIBUTION North America: Mexico.

NOTES Stipeae. N Amer Fl 1994.

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