Stipa pinetorum

HABIT Perennial; caespitose. Culms 10–30 cm long. Leaves mostly basal. Leaf-sheaths glabrous on surface, or puberulous; with reflexed hairs. Ligule an eciliate membrane; 0.5 mm long. Leaf-blades erect; flexuous; filiform; involute; 3–12 cm long; 2.5 mm wide. Leaf-blade surface scaberulous.

INFLORESCENCE Inflorescence a panicle.

Panicle open; linear; 5–12 cm long.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; subterete; 10 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; 0.5 mm long; pubescent; unequally 2-toothed.

GLUMES Glumes persistent; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume linear; 1 length of upper glume; membranous; without keels; 3–5 -veined. Lower glume apex acuminate. Upper glume linear; 10 mm long; hyaline; without keels; 3–5 -veined. Upper glume apex acuminate.

FLORETS Fertile lemma lanceolate; subterete; 6–7 mm long; membranous; without keel; 5 -veined. Lemma surface villous. Lemma margins flat; covering most of palea. Lemma hairs 1.5–2 mm long. Lemma apex dentate; 2 -fid; with lobes 1–1.5 mm long; acute; awned; 1 -awned. Principal lemma awn from a sinus; bigeniculate; 20 mm long overall; with twisted column. Column of lemma awn glabrous. Palea 0.8 length of lemma; 2 -veined; without keels. Palea surface villous.

FLOWER Lodicules 3; 1.5 mm long. Anthers 3; 2 mm long; purple; anther tip smooth. Stigmas 2. Ovary glabrous.

FRUIT Caryopsis with adherent pericarp. Hilum linear.

DISTRIBUTION North America: northwest USA and southwest USA.

NOTES Stipeae. Fl Pac NW 1994.

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