GrassBase - The Online World Grass Flora

Descriptions

W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Poa secunda

HABIT Perennial; caespitose; clumped densely. Butt sheaths herbaceous. Culms erect, or geniculately ascending; 15–120 cm long; wiry. Culm-internodes terete. Leaves mostly basal. Leaf-sheaths with 0–0.25 of their length closed; smooth, or scaberulous. Ligule an eciliate membrane; 1.5–5 mm long; glabrous on abaxial surface, or scaberulous on abaxial surface; entire, or lacerate; acute, or acuminate. Leaf-blades 1–5 cm long; 1–3 mm wide. Leaf-blade surface glabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle open, or contracted; linear to ovate; 2–27 cm long. Primary panicle branches appressed, or ascending, or spreading (in flower); 3–4 -nate. Panicle branches scabrous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 2–6 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; compressed slightly; 3.5–9 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes eventually visible between lemmas; smooth, or scaberulous; glabrous, or sparsely hairy. Floret callus glabrous.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume oblong; 0.9 length of upper glume; membranous; much thinner on margins; 1-keeled; 1–3 -veined. Lower glume lateral veins absent, or obscure. Lower glume surface asperulous; rough above. Lower glume apex acute. Upper glume lanceolate; membranous; with hyaline margins; 1-keeled; 1–3 -veined. Upper glume lateral veins absent, or obscure. Upper glume surface asperulous; rough above. Upper glume apex acute.

FLORETS Fertile lemma oblong; oblong in profile; 4–5 mm long; membranous; keeled; lightly keeled; 5 -veined. Lemma lateral veins with distinct primaries but obscure intermediates. Lemma surface asperulous; glabrous, or puberulous; hairy at base. Lemma apex obtuse, or acute. Palea 0.9 length of lemma. Palea keels scaberulous. Palea surface pubescent; hairy below. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; membranous. Anthers 3; 1–3.8 mm long; yellow, or purple.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION North America: Subarctic, western Canada, eastern Canada, northwest USA, north-central USA, southwest USA, south-central USA, and Mexico. South America: southern South America.

NOTES Poeae. Soreng 1992.

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