GrassBase - The Online World Grass Flora


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

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

Agrostis perennans

HABIT Perennial; caespitose. Culms decumbent; weak; 50–100 cm long; 0.7–1 mm diam. Lateral branches lacking. Leaves cauline. Leaf-sheaths ribbed; smooth; glabrous on surface. Ligule an eciliate membrane; 2–5 mm long; lacerate. Leaf-blades 6–13 cm long; 1.5–3 mm wide. Leaf-blade surface ribbed; scaberulous.

INFLORESCENCE Inflorescence a panicle. Peduncle 8–15 cm long.

Panicle open; ovate; effuse; 11–15 cm long; 6–11 cm wide. Primary panicle branches 3–7 -nate; whorled at most nodes. Panicle branches flexuous.

Spikelets spreading; solitary. Fertile spikelets pedicelled.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets oblong; laterally compressed; 2.2–2.9 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus glabrous.

GLUMES Glumes persistent; similar; exceeding apex of florets; firmer than fertile lemma; shiny; gaping. Lower glume oblong; 2.2–2.9 mm long; 1.1–1.2 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume primary vein scabrous. Lower glume lateral veins absent. Lower glume apex caudate. Upper glume oblong; 1.9–2.3 mm long; 1.1–1.3 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume primary vein scabrous. Upper glume lateral veins absent. Upper glume apex caudate.

FLORETS Fertile lemma ovate; 1.7–1.8 mm long; hyaline; without keel; 5 -veined. Lemma lateral veins obscure; extending close to apex. Lemma apex erose; truncate; muticous. Palea absent or minute.

FLOWER Lodicules 2; membranous. Anthers 3; 0.8–1 mm long; purple.

FRUIT Caryopsis with adherent pericarp. Hilum linear.

DISTRIBUTION Africa: western Indian ocean. North America: eastern Canada, north-central USA, northeast USA, south-central USA, southeast USA, and Mexico. South America: Mesoamericana, Caribbean, northern South America, western South America, and southern South America.

NOTES Aveneae. Fl Costaric 1993.

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