146. Gramineae 329 



3. Spikelets avvnless or nearly so, 2-3.5 cm long, nearly terete; 

 panicle erect, 10-20 cm long, the branches spreading; 

 plants with rhizomes; fields and roadsides; nat. from Eur. 

 May-June. Smooth or Hungarian Brome ...B. iricrrnis Leyss. 

 3. Spikelets conspicuously awned; native species. 



4. Lemmas pubescent on the margins and sometimes near the 

 base, otherwise glabrous; second glume 3-nerved; first 

 glume 1 -nerved; hillsides and open woods. June-Aug. 



B. ciliatus L. 



4. Lemmas evenly pubescent. 



5. Second glume 3-nei-ved; first glume 1 -nerved. 



6. Sheaths (except the lower one or two) shorter than 

 the internodes; blades scarcely auriculate at base; 

 meadows, woods, and banks throughout 111. June- 

 Aug. Canada Brome B. purgans L. 



6. Sheaths longer than the internodes, densely villous 



at the summit; blades somewhat auriculate at base; 

 meadows and open woods, chiefly in the n. half 

 of the state. July-Sept. [B. altissimus Pursh, non 



Gilib. ; B. inconus (Shear) Hitchc] 



B. latiglumis (Shear) Hitchc. 



5. Second glume 5-7-nerved. 



7. Spikelets 3-4 cm long; first glume 1 -nerved; panicle 



12-20 cm long; awns of the lemmas 6-8 mm long; 

 known in 111. from three coll. by V. H. Chase: 

 Wady Petra, Stark Co., in 1900, Woodford Co., in 

 1946, and Peoria Co., in 1953. ...fi. nottowayanus Fern. 

 7. Spikelets 1.5-2.5 cm long; first glume 3-ner\ed; 

 panicle 7-10 cm long; awns of the lemmas 1-3 nmi 

 long; dry ground in open woods in the n. half of 



the state. June-July B. kalmii A. Gray 



2. First glume 3-5-nerved, the second with 5-7 nenes; lemmas 

 keeled; adv. from w. U.S.; waste ground. Cook and Kane 

 counties. June-Aug B. marginatus Nees 



Annual weedy species, nat. from Eur. 



8. Lemmas awnless or the awn not more than 2 mm long; leaves 

 pubescent. 

 9. Panicle loose, 1-sided, the spikelets few, ovate, nodding, 1.5- 

 2.5 cm long; lemmas ovate, awnless, scarious; fields and 



waste places, occasional. June-July. Rattlesnake Grass 



B. hrizaeformis Fisch. & Mey. 



9. Panicle-branches ascending, the spikelets 2-3.5 cm long; 

 lemmas lanceolate, the awn not more than 2 mm long; 

 cult, in s. U.S. and occasionally adv. northward; weed 

 along railroad, Urbana, Champaign Co., H. E. Ahles in 



1953. Rescue Gra.ss [B. calliarticus Vahl, nom. dub.) 



B. willdcnowii Kunth 



8. Lemmas awned. 



