5a. Sheath margins hyaline 



64. Eragrostis spectabilis — Purple Lovegrass 



Leaves rolled in bud-shoot; sheath round, smooth with upper half 

 long hairy, split with overlapping hyaline margins; auricles absent; 

 collar broad; ligule a minute fringe of hairs; blade 5 to 8 mm. wide, 

 long sparse hairy above, smooth below, margins smooth and sparsely 

 long hairy near base. Inflorescence — a diffuse, bright purple panicle two- 

 thirds entire height of plant. Throughout. Sandy soil. 



5b. Sheath margins hairy 



65. Panicum capillare — Witchgrass 



Leaves rolled in bud-shoot ; sheath somewhat flattened, stiff long hairy, 

 split with overlapping margins hairy; auricles absent; collar narrow; 

 ligule a fringe of hairs, about 1 mm. long, fused at base ; blade to 1 7 mm. 

 wide, short hairy above and below, margins rough and short hairy near 

 base. Inflorescence — a very diffuse, densely flowered panicle, about half 

 entire height of plant. Throughout. Cultivated fields, open ground and 

 waste places. 



6a. Plants with large creeping rhizomes 7 



6b. Plants without creeping rhizomes 



66. Setaria lutescens — Yellow Foxtail 



Leaves rolled in bud-shoot; sheath distinctly flattened, smooth, split 

 with overlapping hyaline margins; auricles absent; collar narrow to 

 broad; ligule a fringe of hairs, about 1 mm. long, fused at base; blade to 

 12 mm. wide, long hairy near base above, smooth to somewhat rough be- 

 low, margins smooth to rough. Inflorescence — dense, bristly, cylindrical, 

 yellow, erect, spike-like. Common throughout. Cultivated soil and waste 

 places. 



7a. Sheath round 8 



7b. Sheath distinctly flattened 



67. Tripsacum dactyloides — Eastern Gamagrass 



Leaves rolled in bud-shoot; sheath distinctly flattened, smooth, split 

 with overlapping margins; auricles absent; collar narrow to broad, some- 

 times divided ; ligule a fringe of hairs, .4 to 1 mm. long, sometimes fused 

 at base; blade 20 to 25 mm. wide, rough above and below at least near 

 tip, margins very rough. Inflorescence — 1 to 3 terminal, unisexual spikes. 

 Massachusetts south. Moist places and banks near water. 



24 



