Tragus berteronianus
Plants annual. Culms (2)3.5-45 cm. Ligules 0.5-1 mm; blades (0.5)0.7-8.5 cm long, 1.2-5 mm wide, glabrous. Panicles (1)2-13 cm long, (3)4-8 mm wide; rachises pubescent; branches (0.5)0.7-2.7 mm, pubescent, with 2(3) spikelets, axes occasionally extending past the distal spikelets; proximal internodes 0.2-0.6(0.7) mm, shorter than the second internodes. Proximal spikelets (1.8)2^.3 mm; second spikelets (0.8)1-3.9 mm, some¬times sterile. Lower glumes 0.1-0.6 mm, membranous, minutely pubescent; upper glumes 1.8-4.3 mm, minutely pubescent, 5-veined, rarely with 1-2 additional veins adjacent to the midvein; glume projections (4)6-14, in 5 rows, (0.2)0.3-1 mm, uncinate; lemmas (1.5)1.8-3.1 mm, sparsely pubescent on the back, midveins occasionally excurrent to 0.6 mm; paleas (1.3)1.5-2.4 mm; anthers 3, 0.4-0.6 mm, yellow, occasionally purple-or green-tinged. Caryopses (0.9)1.2-2 mm long, 0.4-0.8 mm wide. 2n = 20.
Distribution
Maine, Puerto Rico, Mass., N.Mex., Tex., Va., Virgin Islands, N.Y., Pacific Islands (Hawaii), S.C., Ariz.
Discussion
Tragus berteronianus is native to Africa and Asia, and is now established in Arizona, New Mexico, and Texas. It was collected in Maine, Massachusetts, New York, and Virginia in the nineteenth century, and Virginia in 1959.
Selected References
None.