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.

Agropyron cristatum

HABIT Perennial; caespitose. Culms decumbent; 20–70 cm long. Leaf-sheath oral hairs lacking. Leaf-sheath auricles falcate. Ligule an eciliate membrane; 2 mm long. Leaf-blades involute; 6–12 cm long; 1.5–3 mm wide; stiff.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; oblong; bilateral; 1–5 cm long; 10–20 mm wide. Rhachis pilose on surface. Spikelet packing broadside to rhachis. Rhachis internodes oblong.

Spikelets pectinate; solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 3–8 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; compressed strongly; 8–15 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; shorter than spikelet; firmer than fertile lemma. Lower glume ovate; 3–5 mm long; 1 length of upper glume; coriaceous; 1-keeled; keeled all along; 3 -veined. Lower glume surface glabrous, or pilose. Lower glume apex acuminate; awned; 1 -awned. Lower glume awn 1–2 mm long. Upper glume ovate; 3–5 mm long; 0.66 length of adjacent fertile lemma; coriaceous; 1-keeled; keeled all along; 3 -veined. Upper glume lateral veins convergent at apex. Upper glume surface glabrous, or pilose. Upper glume apex acuminate; awned; 1 -awned. Upper glume awn 1–2 mm long.

FLORETS Fertile lemma elliptic; 5–7 mm long; chartaceous; keeled; keeled above; 5 -veined. Lemma surface pilose. Lemma apex acuminate; awned; 1 -awned. Principal lemma awn 3–4 mm long overall; limb scabrous. Palea keels scabrous. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Ovary with a fleshy appendage below style insertion; pubescent on apex.

FRUIT Caryopsis with adherent pericarp; oblong; sulcate on hilar side; hairy at apex; apex fleshy. Embryo 0.2 length of caryopsis. Hilum linear; 1 length of caryopsis. Disseminule comprising a floret.

DISTRIBUTION Europe: central, southwestern, southeastern, and eastern. Africa: north. Asia-temperate: Siberia, Soviet far east, Soviet Middle Asia, Caucasus, western Asia, China, and Mongolia. Asia-tropical: India. North America: Subarctic, western Canada, eastern Canada, north-central USA, and northeast USA.

NOTES Triticeae. Fl Iraq.

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