Digitaria velutina (Forssk.) P. Beauv.
Poaceae
Paniceae
velvet fingergrass, annual couchgrass
spikelet, disarticulation below the glumes
Spikelets of 1 fertile floret and 1 basal sterile lemma. Spikelets elliptic to lanceolate, dorsally compressed, plano-convex, 1.5–2.1 mm long, 0.5–0.6 mm wide. Pubescent, with short to long hairs between nerves on upper glume and sterile lemma. Glumes dissimilar; lower glume a small scale or absent; upper glume membranous, 1.2–1.6 mm long. Sterile lemma membranous, as long as spikelet. Fertile lemma gray to brown at maturity, cartilaginous, striate, as long as spikelet, with flat margins covering much of palea.
Fertile lemmas in the genus Digitaria are flat and thinner at the margins. See Digitaria abyssinica (Hochst. ex A. Rich.) Stapf.
Digitaria horizontalis Willd. (non-FNW)
widespread in tropical Africa, including South Africa; Asia: China, India, Japan, Korea, Malaysia, Taiwan; Oceania: Micronesia; North America: Costa Rica, United States
native to eastern Africa
sandy soils, damp places; fields, plantations, open brush
Digitaria velutina is a slender, annual grass, up to 100 cm tall. It is a quickly invading, common weed of arable land in Africa. Propagation is by the grains, which are highly viable. This grass has been used as a forage plant.
A, spikelet in ventral view showing sterile lemma; B, spikelet in dorsal view showing upper glume and fertile lemma; C, floret in ventral view showing palea and margins of lemma; D, floret in dorsal view showing lemma; E, caryopsis in ventral view; F, caryopsis in dorsal view; drawing by Lynda E. Chandler |