GROUP 16 



la. Leaves folded in bud-shoot 



201. Lolium perenne — Perennial Ryegrass 



Leaves folded in bud-shoot; sheath round to somewhat flattened, 

 smooth, split with overlapping hyaline margins; auricles small; collar 

 narrow to medium broad, divided; ligule membranous, .6 to 2 mm. long, 

 truncate to rounded; blade to 6 mm. wide, smooth to rough above, 

 smooth and glossy and keeled below, margins smooth and hyaline. 

 Inflorescence— long, narrow, flat spikes with unawned spikelets placed 

 edge to rachis. Cultivated throughout. 



lb. Leaves rolled in bud-shoot 



2a. Plants with white creeping rhizomes 



202. Agropyron repens — Quackgrass 



Leaves rolled in bud-shoot; sheath round, mostly short hairy, split 

 with overlapping hyaline margins; auricles small; collar mostly medium 

 broad, may be divided, sometimes minutely hairy; ligule membranous, 

 mostly .2 to .4 mm. long but occasionally to 1 mm., truncate to rounded, 

 may be finely toothed or ciliate; blade 5 to 12 mm. wide, rough and 

 mostly hairy above, mostly keeled and smooth or short hairy below, 

 margins rough (rarely short hairy) and hyaline. Inflorescence— a long, 

 narrow spike with spikelets placed side to rachis. Common throughout. 



Fields, meadows and waste places. 



o 

 2b. Plants without creeping rhizomes 



3a. Plant glaucous, a cultivated winter annual 



203. Secale cereale— Rye 



Leaves rolled in bud-shoot; sheath round, smooth, split with overlap- 

 ping hyaline margins; auricles small; collar mostly broad; ligule mem- 

 branous, 1 to 1.6 mm. long (Tetra Petkus, mostly longer), rounded, 

 lacerate, may be ciliate; blade 8 to 18 mm. wide, glaucous above and be- 

 low, rough above, smooth and keeled below at least near base, margins 

 rough and hyaline. Inflorescence— a narrow, crowded spike. Cultivated 

 winter annual. 



3b. Plants not glaucous 



4a. Auricles hairy 



4b. Auricles not hairy 6 



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