GRAMINEAE (GRASS FAMILY) 77 



at length adhering to the prominent groove in the linear smooth amber- 

 colored grain. 



Annuals (introduced). 

 Lemma awned. 



Awn longer than the glume . . . . . . 1. B. tectorum. 



Awn shorter than the glume 2. B. secalinus. 



Lemma not awned . . . . . . . . 3. B. brizaeformis. 



Perennials (indigenous except No. 4). 



Lower glume 1-nerved; the upper 3-nerved. 



Sheaths and leaves smooth or nearly so . . . . . 4. B. inermis. 



Sheaths and leaves more or less pubescent or scabrous. 



Panicle erect 5. B. Pumpellianus. 



Panicle dropping. 



Leaves pilose on both sides or nearly glabrous . . 6. B. ciliatus. 

 Leaves scabrous above, glabrous below . . . 7. B. Richardsonii. 



Lower glume 3-nerved; the upper 3-7-nerved. 



Panicle drooping . . . . . . . . . 8. B. Porteri. 



Panicle erect. 



Sheaths and leaf-blades pilose . . . . . 9. B. marginatus. 



Sheaths and leaf-blades smooth or scabrous . . . . 10. B. polyanthus. 



1. Bromus tectorum L. Sp. PI. 77. 1753. Culms 1.5-6 dm. tall, erect from 

 an annual root: sheaths, at least the lower ones, softly pubescent; leaves 2.5-10 

 cm. long, 2-4 mm. wide, softly pubescent: panicle 5-15 cm. in length, open, 

 the branches slender and drooping, somewhat one-sided : spikelets numerous, 

 5-8-flowered, on capillary recurved slender pedicels:, glumes acuminate, 

 usually rough or hirsute, the first 1-nerved, the second longer, 3-nerved; 

 lemma 8-12 mm. long, acuminate, 7-nerved, usually rough or hirsute; awn 

 1.2-1.6 cm. long. A weed naturalized from Europe; rare in our range. 



2. Bromus secalinus L. 1. c. 76. Culms 4-8 dm. high: panicle 1-2 dm. long, 

 pyramidal; branches mostly in fours or fives, verticillate, nearly smooth: 

 spikelets 1-2 cm. long, 5-10-flowered; florets turgid: glumes obtuse or sub- 

 acute; lemma obtuse, denticulate, mucronate or short-awned, smooth, 7- 

 nerved: grain concavo-convex. Closely allied and probably to be referred 

 here is B. racemosus L. 1. c. This is the CHESS or CHEAT so often found in 

 wheat fields. 



3. Bromus brizaeformis Fisch & Mey. Ind. Sem. Hort. Petrop. 3: 30. 1836. 

 Culms 2-6 dm. tall: sheaths, at least the lower, pubescent with soft villous 

 hairs; leaves 2.5-17.5 cm. long, 2-6 mm. wide, pubescent: panicle 4-20 cm. 

 in length, open, the branches ascending or often drooping, flexuous: spikelets 

 few, 1.25-2.5 cm. long, laterally much compressed: glumes very obtuse, often 

 purplish, glabrous or minutely pubescent, the first 3-5-nerved, the second 

 larger, 5-9-nerved; lemma 6-8 mm. long, very broad, obtuse, 9-nerved, shin- 

 ing, glabrous or sometimes minutely pubescent, awnless. QUAKE BROME 

 GRASS. An introduction from northern Europe or Asia; only occasionally 

 found in our range. 



4. Bromus inermis Leyss. Fl. Hal. 16. 1761. Culms tufted, 8-12 dm. tall: 

 sheaths smooth and glabrous; leaves 1.5-2.5 dm. long, 4-6 mm. wide, smooth 

 and glabrous: panicle 1.5-2.5 dm. long, oblong, the axis scabrous, its scabrous 

 branches ascending, in clusters: spikelets 2-2.5 cm. long, about 5 mm. wide, 

 oblong, erect: first glume 1-nerved, the second 3-nerved; lemma 10-12 mm. 

 long, 5-7-nerved, awnless, or rarely awn-pointed. SMOOTH or HUNGARIAN 

 BROME GRASS. Introduced and extensively grown for hay; often an escape 

 from cultivation. 



5. Bromus Pumpellianus Scribn. Bull. Torr. Bot. Club 15: 9. 1888. Stout 

 erect perennial, with creeping rootstocks: culms smooth or sparingly pilose- 

 pubescent: leaves smooth below, scabrous or pubescent above, 1-2 dm. long: 

 panicle narrow, erect, 10-20 cm. long: spikelets 7-11-flowered, 2-3 cm. long: 

 glumes smooth; the lower 1-nerved, acuminate, 6-8 mm. long; the upper 

 broader and longer, 3-nerved; lemma 5-7-nerved, 10-12 mm. long, densely 

 and coarsely ciliate-pubescent on the margin nearly or quite to the apex and 

 across the back at the base, the awn usually 2-3 mm. long; palet nearly as 

 long as the glume; rachilla pilose-pubescent. Colorado and far northward 

 and westward. 



