82 GRAMINEAE (GRASS FAMILY) 



Spikes bushy, with spreading awns 1. H. jubatum. 



Spikes narrow, with nearly erect awns. 



Glumes aristiforrn . . . . . . . . . . 2. H. nodosum. 



Glumes dilated above 3. H. pusillum. 



1. Hordeum jubatum L. Sp. PI. 85. 1753. Short-lived perennial or annual: 

 culms 2-5 dm. high: spike 1 dm. long or less, liglit green or yellow, very 

 fragile; lateral flowers reduced to awns slightly exceeding the perfect floret: 

 glumes aristiform, slightly exceeded by the awn of the perfect floret. 

 Prairies, Texas to Minnesota and westward; a very troublesome weed, in 

 meadows; commonly called FOXTAIL, but more properly SQUIRRELTAIL GRASS. 



2. Hordeum nodosum L. Sp. PI. Ed. 2. 56. 1762. Perennial (?): culms 4-8 

 dm. high: spike narrow, 4-8 dm. long, usually dark green or purple; lateral 

 spikelets staminate or neutral, awnless: glumes aristiform, about 1 cm. long, 

 equaling the awn of the perfect floret. WILD BARLEY. Common in our range 

 in saline soils; extending to Arizona and Alaska. 



3. Hordeum pusillum Nutt. Gen. 1: 87. 1818. Annual>culms 3-5 dm. 

 high, slender, weak: spikes 3-6 cm. long; lateral spikelets staminate or neutral, 

 awnless: four anterior empty glumes broadened above the narrow stalk-like 

 base, tapering above into a rigid awn about 1 cm. long, equaling the awn of 

 the perfect floret. From Idaho to Arizona and eastward through the southern 

 States. 



64. ELYMUS L. WILD RYE. LYME GRASS 



Rather coarse grasses with flat rough leaves. Spikelets 2-7-flowered, all 

 perfect except the upper florets, compressed, sessile in clusters or 2 to 4 at each 

 node in the spike. Glumes nearly side by side in front of the spikelets, 2 for 

 each, thickened and nervose or aristiform; lemma coriaceous or rigid, convex, 

 very acute or awned, nearly equaled by the palet. Grain linear, channeled, 

 adhering to the palet and enveloping lemma. 



Lemma conspicuously awned. 



Spikelets divergent from the rachis of the broad spike . . . 1. E. canadensis. 

 Spikelets appressed to the rachis of the narrower spike. 



Spikelets 3-6-flowered 2. E. glaucus. 



Spikelets 1-3-flowered 3. E. Macounii. 



Lemma short-awned or merely acute. 



Relatively low and slender, usually less than 1 m. high. 



Spike densely villous-pubescent . . . . . . . 4. E. innovatus. 



Spike glabrate. 



Flowering glume 7-nerved above . . . . . . 5. E. triticoides. 



Flowering glume indistinctly 5-nerved. 



Leaves smooth or merely roughened . . . . . 6. E. ambiguus. 



Leaves pubescent beneath . . . . . . . 7. E. salinus. 



Tall and coarse, tufted, often 2 m. high 8. E. condensatus. 



1. Elymus canadensis L. Sp. PI. 83. 1753. Culms stout, 5-10 dm. high: 

 spike usually nodding, 1-2 dm. long: spikelets mostly in pairs, 3-5-flowered, 

 hispid or pubescent throughout: glumes narrowly lanceolate, indistinctly 

 3-nerved, tapering into a rather rigid awn 1-2 cm. long and about one half as 

 long as the divergent awns of the 5-nerved lemma. The following are very 

 closely related if indeed they be not mere forms of this: E. robustus Scribn. & 

 Sm. U. S. Dept. Agr. Div. Agrost. Bull. 4: 37. 1897; E. Ursutiglumis Scribn. & 

 Sm. 1. c. 11: 56. 1898; E. brachystachys Scribn. & Ball, 1. c. 24: 47. 1900. 

 Across the continent northward, and south through our range to 'New Mexico 

 and Texas. 



2. Elymus glaucus Buckley, Proc. Acad. Phila. 1863: 99. Culms 6-15 dm. 

 tall: sheaths rarely pubescent: leaves 1-3 dm. long, 4-16 mm. wide, smooth 

 beneath, sometimes rough above: spike 7.5-20 cm. in length, narrow, slender: 

 spikelets appressed to the rachis, 3-6-flowered: glumes narrowly lanceolate, 

 8-12 mm. long, acuminate or awn-pointed, rigid, 3-5-nerved; lemmas smooth 

 or slightly rough, 1-1.2 cm. long, bearing a slender straight rough awn 1.2-1.8 

 cm. in length. E. sibiricus. Throughout our range and west to the Pacific 

 States. 



3. Elymus Macounii Vasey, Bull. Torr. Bot. Club 13: 119. 1886. Culms 



