Digitaria ischaemum

HABIT Annual; caespitose. Culms geniculately ascending, or decumbent; 10–35 cm long; 2–4 -noded. Leaf-sheaths glabrous on surface. Ligule an eciliate membrane; 1–2 mm long. Leaf-blades 2–12 cm long; 2–7 mm wide.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 2–8; digitate; unilateral; 1.5–7 cm long. Rhachis narrowly winged; angular; scabrous on margins.

Spikelets appressed; in threes. Fertile spikelets pedicelled; 3 in the cluster.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; subacute; 2–2.5 mm long; falling entire.

GLUMES Glumes one the lower absent or obscure; reaching apex of florets; thinner than fertile lemma. Upper glume elliptic; 1 length of spikelet; membranous; 3 -veined. Upper glume surface pubescent; hairy between veins; with clavate hairs. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic; 1 length of spikelet; membranous; 7 -veined; with equidistant veins; pubescent; hairy between veins; with clavate hairs; obtuse. Fertile lemma elliptic; 2–2.5 mm long; cartilaginous; much thinner on margins; dark brown; without keel. Lemma margins flat; covering most of palea. Lemma apex acute. Palea cartilaginous.

FLOWER Anthers 3; 0.5–0.7 mm long.

FRUIT Hilum punctiform.

DISTRIBUTION Europe: northern, central, southwestern, southeastern, and eastern. Asia-temperate: Siberia, Soviet far east, Soviet Middle Asia, Caucasus, western Asia, China, Mongolia, and eastern Asia. Asia-tropical: India. Australasia: Australia and New Zealand. North America: western Canada, eastern Canada, northwest USA, north-central USA, southwest USA, and southeast USA. South America: Caribbean.

NOTES Paniceae. CEH.

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