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.

Brachyelytrum aristosum

HABIT Perennial. Rhizomes short. Culms 28.5–96 cm long; 0.6–1 mm diam. Culm-internodes 3.9–15.5 cm long; distally glabrous, or pubescent. Culm-nodes pubescent. Leaves cauline. Leaf-sheaths 3.2–10.4 cm long; pubescent. Ligule an eciliate membrane; 1.8–2.5 mm long. Leaf-blades linear, or lanceolate; 6.9–16.1 cm long; 8–16 mm wide. Leaf-blade venation without cross veins, or with obscure cross veins. Leaf-blade surface pilose; sparsely hairy; hairy on both sides. Leaf-blade margins scabrous; ciliate.

INFLORESCENCE Inflorescence a panicle; comprising 8–55 fertile spikelets.

Panicle open; linear, or oblong; 6.6–17.5 cm long; 0.4–0.8 cm wide; bearing many spikelets, or few spikelets. Primary panicle branches 1–7 in number; indistinct the panicle almost racemose, or simple, or sparsely divided.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; with a barren rhachilla extension. Spikelets lanceolate; dorsally compressed; 9–10 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; pilose.

GLUMES Glumes persistent; dissimilar; shorter than spikelet; thinner than fertile lemma. Lower glume ovate; 0.1–0.9 mm long; 0.15–0.3 length of upper glume; membranous; without keels; 0 -veined. Lower glume lateral veins absent. Lower glume apex acute. Upper glume lanceolate; 0.6–3 mm long; 0.3–0.6 length of adjacent fertile lemma; membranous; without keels; 1(–3) -veined. Upper glume apex acute.

FLORETS Fertile lemma elliptic; 9–10 mm long; 0.7–1.4 mm wide; herbaceous; without keel; 5 -veined. Lemma lateral veins obscure. Lemma surface scaberulous; glabrous. Lemma apex acuminate; awned; 1 -awned. Principal lemma awn 14–26 mm long overall. Palea tightly convolute around flower; 7.7–11.5 mm long; 2 -veined. Rhachilla extension 4–6.9 mm long.

FLOWER Lodicules 2. Anthers 2; 2–3.5 mm long. Stigmas 2.

FRUIT Caryopsis with tardily free pericarp; linear; 5.5–7.5 mm long; light brown, or dark brown.

DISTRIBUTION North America: north-central USA, northeast USA, and southeast USA.

NOTES Brachyelytreae. Saarela et al 2004.

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