Plants with long rhizomes. Culms 2-4 m tall, 0.6-2 cm thick, solitary
or few together. Sheaths usually glabrous; ligules 1.5-3 mm; blades
50-100 cm long, 10-25 mm wide, usually glabrous, markedly hirsute above the ligules.
Peduncles pilose; panicles 40-70 cm, narrowly oblong to widely ovate,
rachises 25-50 cm, densely pilose; primary branches 2.5-7 cm. Sessile
spikelets 3.5-7 mm. Callus hairs to 12 mm; glumes glabrous over
the back, ciliate toward the tip; lower lemmas about 3 mm; upper lemmas
subequal to the lower lemmas, entire; awns absent; anthers 3. Pedicels
1.5-3 mm, ciliate. Pedicellate spikelets similar to the sessile spikelets.
2n = 20, 24-30, 32, 36, 38, 40, 48-60, 64, 69.
Saccharum spontaneum is a weedy species, native to tropical Africa and
Asia, that is now established in Mesoamerica but not, so far as is known, in the
Flora region. It is listed as a noxious weed by the U.S. Department of
Agriculture, but it is grown in breeding programs as a source of potentially useful
genes for S. officinarum (sugar cane), with which
it readily hybridizes. Because of the potential economic damage of uncontrolled
hybridization between S. spontaneum and S. officinarum, the U.S.
Department of Agriculture should be notified of plants found growing outside a