Pennisetum setaceum	Pennisetum advena	Pennisetum alopecuroides	Pennisetum orientale	Pennisetum villosum
no secondary branching, leaf width 1-3(-4) mm	with secondary branching, leaf width (2-)6-11 mm	leaf width (1-)2-11(-14) mm	leaf width 3-12(-15) mm	leaf width 2-6 mm
peduncle with few short hairs	peduncle rough to the touch	peduncle pubescent	peduncle glabrous	peduncle pubescent
longest bristle 20-35 mm, 1-3 spikelets per fascicle	longest bristle 13-34 mm, 1-4 spikelets per fascicle	longest bristle 8-35 mm, 1-2 spikelets per fascicle	longest bristle 14-31 mm, 1-4 spikelets per fascicle	longest bristle 20-50 mm, 1 spikelet per fascicle
Photos: P. villosum 1 & 2: G. Fried