MANUAL OF THE GRASSES OF THE UNITED STATES 487 



1. Schedonnardus paniculatus (Nutt.) Trel. TUMBLEGRASS. (Fig. 

 1034.) Culms 20 to 40 cm tall; leaves crowded at the base; blades 

 flat, mostly 2 to 5 cm long, about 1 mm wide, wavy; spikes 2 to 10 

 cm long; spikelets narrow, acuminate, about 4 mm long. The axis 

 of the inflorescence elongates after flowering, becoming 30 to 60 cm 

 long, curved in a loose spiral; the whole breaks away at maturity and 

 rolls before the wind as a tumbleweed. 91 -Prairies and plains, 

 Illinois to Saskatchewan and Montana, south to Texas and Arizona; 

 Argentina (fig. 1035). This species forms an 

 inconsiderable part of the forage on the Great 

 Plains. 



98. BECKMANNIA Host. SLOUGHGRASS 



Spikelets 1- or 2-flowered, laterally com- 

 pressed, subcircular, nearly sessile and closely 

 imbricate, in two rows along one side ol a slender 

 continuous rachis, disarticulating below the glumes, falling entire; 

 glumes equal, inflated, obovate, 3-nerved, rounded above but the 

 apex apiculate; lemma narrow, 5-nerved, acuminate, about as long 

 as the glumes; palea nearly as long as the lemma. Erect, rather 

 stout annuals with flat blades and numerous short appressed or as- 

 cending spikes in a narrow more or less interrupted panicle. Type 

 species, Beckmannia erucaejormis (L.) Host, to which our species 

 was formerly referred. Named for Johann Beckmann. 



1. Beckmannia syzigachne (Steud.) Fernald. AMERICAN SLOUGH- 

 GRASS. (Fig. 1036.) Light green; culms 30 to 100 cm tall; panicle 10 

 to 25 cm long, the erect branches 1 to 5 cm long; spikes crowded, 1 to 

 2 cm long; spikelets 1-flowered, 3 mm long; glumes transversely 

 wrinkled and with a deep keel, the acuminate apex of the lemma 

 protruding, o Marshes and ditches, Manitoba to Alaska, south 

 to Illinois, Kansas, New Mexico, and California; New York, Ohio 

 (fig. 1037); Asia. The European B. erucaejormis (L.) Host has 2- 

 flowered spikelets. Our species is palatable to stock, sometimes suffi- 

 ciently abundant locally to be an important forage grass, and is not 

 infrequently cut for hay. 



99. SPAETINA Schreb. CORDGRASS 



Spikelets 1-flowered, much flattened laterally, sessile and usually 

 closely imbricate on one side of a continuous rachis, disarticulating 

 below the glumes, the rachilla not produced beyond the floret; glumes 

 keeled, 1-nerved, acute or short-awned, the first shorter, the second 

 often exceeding the lemma; lemma firm, keeled, the lateral nerves 

 obscure, narrowed to a rather obtuse point; palea 2-nerved, keeled 

 and flattened, the keel between or at one side of the nerves. Erect, 

 often stout tall perennials, with usually extensively creeping, firm, 

 scaly rhizomes (wanting in Spartina spartinae, S. bakeri, and some- 

 times in S. patens var. caespitosa) , long tough blades, and two to many 

 appressed or sometimes spreading spikes racemose on the main axis, 

 the slender tips of the rachises naked, often prolonged. Type species, 

 Spartina schreberi Gmel. Name from Greek spartine, a cord made 

 from spartes (Spartiumjunceum), probably applied to Spartina because 

 of the tough leaves. 



