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.

Agrostis infirma

HABIT Perennial. Rhizomes absent, or short. Basal innovations extravaginal, or intravaginal. Culms erect, or geniculately ascending; 40–85 cm long; rooting from lower nodes. Leaf-sheaths smooth. Ligule an eciliate membrane; 4–7 mm long; erose; truncate, or obtuse, or acute. Leaf-blades flat, or involute; 10–25 cm long; 3–6.5 mm wide. Leaf-blade surface smooth, or scabrous.

INFLORESCENCE Inflorescence a panicle.

Panicle open, or contracted; lanceolate, or elliptic; 15–30 cm long. Primary panicle branches 2–11 cm long. Panicle branches smooth, or scabrous.

Spikelets solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; 1.5–4.1 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent. Floret callus hairs 0.1–0.3 mm long; 0.1 length of lemma.

GLUMES Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma; shiny; gaping. Lower glume lanceolate; 1.5–4.1 mm long; 1.1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex acuminate. Upper glume lanceolate; 1.4–4 mm long; 1.2 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume apex acuminate.

FLORETS Fertile lemma oblong; 1.2–3.25 mm long; hyaline; without keel; 5 -veined. Lemma lateral veins extending close to apex. Lemma apex erose; truncate, or obtuse, or acute; muticous, or awned; 1 -awned. Principal lemma awn dorsal; arising 0.3–0.8 way up back of lemma; geniculate; 2–4 mm long overall; with twisted column. Palea 0.1–2 mm long; 0.1–0.75 length of lemma; hyaline.

FLOWER Lodicules 2; membranous. Anthers 3; 0.55–1.4 mm long.

FRUIT Caryopsis with adherent pericarp. Hilum linear.

DISTRIBUTION Asia-temperate: China and eastern Asia. Asia-tropical: Malesia and Papuasia.

NOTES Aveneae. Veldkamp 1994.

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