GRASSES OF OHIO 
299 
Tribe, Agrostideae. Bent-grass Tribe. 
Grasses zvith more or less laterally compressed spikelets jointed 
above the empty glumes and arranged in panicles or racemes; spikelets 
1- flozvcred, the rachilla sometimes prolonged behind the palet into a 
naked or plumose bristle. 
35. Sporobolus R. Br. Rush-grass, Dropseed. 
Perennial or rarely annual grasses with flat or convolute leaves 
and open or contracted panicles, our species with a peculiar constric¬ 
tion about the middle of the leaf blade. Spikelets usually small, 1- 
flowered, awnless; empty glumes ^usually unequal, membranous; 
lemma 1-nerved, equaling or longer than the empty ones; palet 
2- nerved, often splitting at maturity; grain free, readily falling from 
the spikelet. 
1. Panicle contracted. 2 
1. Panicle open, its branches spreading; stems tufted; perennials. 5 
2. Lemma pubescent. 3 
2. Lemma glabrous. 4 
3. Panicle 2-5 in. long, its branches 1-2 in. long; palet long-acuminate; perennial. 
5. clandestinus. 
3. Panicle 1-2 in. long, its branches in. long or less; palet long-acute; annual. 
S. vaginaedoTus. 
4. Panicle 3-10 in. long; sheaths cylindric; palet obtuse; perennial. S. asper. 
4. Panicle 1-214 in. long, sheaths inflated; palet acute; annual. S. neglectus. 
5. Spikelets in. long or less; empty glumes ovate to lanceolate, leaf sheaths 
densely pilose at the throat. 5. cryptandrus. 
5. Spikelets nearly in. long; outer empty glumes subulate, leaf sheaths glabrous 
or sparingly pilose at the summit. S. heterolepis. 
1. Sporobolus asper (Mx.) Kunth. Longleaf Rush-grass. A 
perennial grass with stout, erect, simple or occasionally branched 
stems, 1^-3^ ft. high and terminal linear panicles, partly included 
in the inflated upper sheath. Lemma glabrous, acutish or obtuse. 
In dry sandy soil. Aug., Sept. Lake, Erie, Franklin. 
2. Sporobolus vaginaeflorus Torr. Sheathed Rush-grass. An 
annual grass with tufted, slender stems, ^-1^2 ft. high, and numerous 
panicles partly included in the inflated sheath, the terminal one 
exserted. Lemma acuminate, scabrous, shorter than the sharp- 
pointed palet. 
In dry soil. Aug., Sept. Auglaize, Madison, Warren, Vinton, 
Athens. 
3. Sporobolus neglectus Nash. Small Rush-grass. An annual 
grass with erect slender often much branched, usually decumbent 
