3b. Ligule 3 mm. or less long 



1/ 



4a. Blade margins hairy 



125. Bromus rigidus — Ripgut Grass 



Leaves rolled in bud-shoot; sheath round, hairy, closed to near top; 

 auricles absent; collar narrow, mostly hairy; ligule membranous, 3 to 5 

 mm. long, rounded, toothed; blade 5 to 10 mm. wide, hairy above and 

 below, margins short hairy or sometimes very rough. Inflorescence— an 

 open, nodding, few-flowered panicle with stout awns to 6 in. long. Mary- 

 land south, rare. Open ground and waste places. 

 4b. Blade margins not hairy 



126. Bromus catharticus — Rescue Grass 



Leaves rolled in bud-shoot; sheath round to somewhat compressed, 

 short hairy, closed to near top; auricles absent; collar medium broad to 

 broad, divided; ligule membranous, 3 to 6 mm. long, rounded, sometimes 

 toothed; blade 7 to about 12 mm. wide, mostly rough above and below 

 but sometimes hairy on one or both surfaces, margin rough or occasion- 

 ally short hairy. Inflorescence— an open, nodding panicle. Only rarely 

 north of Virginia. Waste places. 



5a. Blade hairy above 



5b. Blade not hairy above 



127. Bromus inermis — Smooth Bromegrass 



Leaves rolled in bud-shoot; sheath round, smooth or frequently short 

 hairy on lower sheaths, closed to near top; auricles absent; collar mostly 

 medium broad to broad and divided; ligule membranous, mostly less 

 than 1 mm. long, truncate to rounded; blade generally to 10 to 15 mm. 

 wide, smooth above and below (rarely short hairy), margins smooth to 

 rough. Inflorescence— an erect, dense panicle. South to Maryland. 

 Fields and waste places. 



6b. Sheath densely soft white hairy 9 



6b. Sheath not densely soft white hairy 7 



7a. Collar hairy at least on margins 

 128. Bromus sterilis — Barren Chess 



Leaves rolled in bud-shoot; sheath round, short hairy, closed to near 

 top; auricles absent; collar narrow to medium broad, divided, hairy; 

 ligule membranous, 2 to about 3 mm. long, rounded, toothed, may be 

 ciliate; blade 5 to 9 mm. wide, short hairy above and below, margins 

 hairy. Inflorescence— an open, nodding few-flowered panicle with awns 

 to about 1 in. long. Throughout. Not common. Fields and waste places. 



NOTE: The bromegrasses are quite variable in their vegetative char- 

 acteristics and it is not possible to always readily separate the species. The 

 key given here is based on the characteristics most commonly found. 



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