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MISC. PUBLICATION 200, U. S. DEPT. OF AGRICULTURE 



ciliatus and can scarcely be ranked 

 even as a variety. This is the common 

 form in the Rocky Mountains. 



20. Bromus purgans L. Canada 

 brome. (Fig. 19.) Resembling B. 

 ciliatus; nodes mostly 4 to 6 ; sheaths, 

 except the lower 1 or 2, shorter than 

 the internodes, more or less retrorsely 

 pilose, or sometimes all glabrous; 

 blades elongate, 5 to 17 mm. wide, 

 narrowed at base, and without flanges 

 or auricles; pubescence of lemma 

 nearly uniform, sometimes more dense 

 on the margins, sometimes sparse 

 and short on the back or scabrous 

 only. 9j — Moist woods and rocky 

 slopes, Massachusetts to North Da- 

 kota, south to northern Florida and 

 Texas. 



Figuhe 19. — Bromus purgans. 

 Floret, X 5. (Deam 27982, Ind.) 



Bromus purgans var. laevigltj- 

 mis (Scribn.) Swallen. Culms stout, 

 leafy, mostly more than 1 m. tall; 

 sheaths shorter or longer than the 

 internodes, glabrous to pubescent, 

 not strongly pilose; blades elongate, 

 as much as 1 cm. wide or even wider; 

 panicle large, open; lemmas glabrous 

 or nearly so. % — Woods and river 

 banks, rare. Known from Quebec, 

 Ontario, Maine, Vermont, Connecti- 

 cut, New York, Michigan, Wisconsin, 

 Maryland, West Virginia, and North 

 Carolina. 



21. Bromus latiglumis (Shear) 

 Hitchc. (Fig. 20.) Differing from B. 



purgans in having usually 10 to 20 

 nodes; sheaths overlapping, more or 

 less pilose, especially about the throat 

 and collar; base of blades with 

 prominent flanges on each side, these 

 usually prolonged into auricles. Where 

 the ranges of B. purgans and B. 

 latiglumis overlap, the latter flowers 

 several weeks later than the former. 

 Qi — Alluvial banks of streams, 

 Quebec and Maine to North Dakota, 

 south to North Carolina and Kansas. 



Figure 20. — Bromus latiglumis. Base of 

 blades, X 1. (Type.) 



Bromus latiglumis f. incanus 

 (Shear) Fernald. Culms 1 to 2 m. 

 tall, decumbent below, mostly some- 

 what weak and sprawling; sheaths 

 densely canescent; panicles rather 

 heavy. % — Low woods, Indiana, 

 Illinois, Michigan, and Maryland. 



22. Bromus nottowayanus Fern- 

 ald. (Fig. 21.) Resembling B. lati- 

 glumis, but with fewer nodes; sheaths 

 mostly longer than the internodes, 

 usually retrorsely pilose, without 

 flanges at the mouth; ligule very 

 short; blades elongate, 6 to 13 mm. 

 wide, pilose above, some sparsely so 

 beneath; panicles 12 to 22 cm. long, 

 the slender branches drooping, the 

 pulvini inconspicuous; first glume 1- 

 to 3-nerved, the second 5-nerved; 

 lemma 8 to 13 mm. long, densely 

 appressed-pilose, the awn 5 to 8 mm. 

 long. % — Rich woods, Indiana 

 and Illinois; Maryland to North 

 Carolina; Tennessee; Arkansas. 



