Digitaria serotina

HABIT Annual; caespitose. Culms decumbent; 20–50 cm long; rooting from lower nodes. Lateral branches ample. Leaf-sheaths hirsute; with tubercle-based hairs. Ligule an eciliate membrane. Leaf-blades ascending; lanceolate; 5–10 cm long; 3–10 mm wide. Leaf-blade surface pubescent; hairy on both sides; with tubercle-based hairs.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 2–6; digitate; erect, or ascending; unilateral; 2.5–10 cm long. Central inflorescence axis 1–2 cm long. Rhachis broadly winged.

Spikelets in pairs, or in threes. Fertile spikelets pedicelled; 2–3 in the cluster. Pedicels terete; glabrous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; acute; 1.5–1.7 mm long; falling entire.

GLUMES Glumes one the lower absent or obscure; shorter than spikelet; thinner than fertile lemma. Upper glume elliptic; 0.33 length of spikelet; membranous; without keels; 3 -veined. Upper glume surface pubescent. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic; 0.9 length of spikelet; membranous; 7 -veined; pubescent; acute. Fertile lemma elliptic; 1.5–1.7 mm long; cartilaginous; much thinner on margins; pallid; without keel. Lemma margins flat; covering most of palea. Lemma apex acute. Palea cartilaginous.

DISTRIBUTION North America: northeast USA and southeast USA. South America: Caribbean.

NOTES Paniceae. N Amer Fl 1994.

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