

MANUAL OF THE GRASSES OF THE UNITED STATES 489 



The species with rhizomes often form extensive colonies to the ex- 

 clusion of other plants. They are important soil binders and soil 

 builders in coastal and interior marshes. A 

 European species, S. townsendi H. and J. Groves, 

 has in recent years assumed much importance, 

 especially in southern England, the Netherlands, 

 and northern France, as a soil builder along 

 the coast where it is reclaiming extensive areas 

 of marsh land. The marsh hav of the Atlantic 

 coast, much used for > packing and formerly Fl |SS«1^ff mof 

 for bedding, often consists largely of S. patens. 



Blades usually more than 5 mm wide, flat when fresh, at least at base, the tip 

 involute; plants mostly robust and more than 1 m tall. 

 First glume as long as the floret, slender-acuminate, the second with an awn 

 as much as 7 mm long; spikes somewhat distant, mostly more or less 



spreading 1. S. pectin - ata. 



First glume shorter than the floret, acute, the second acute or mucronate but 

 not slender-awned; 6pikes approximate, usually appressed. 

 Blades very scabrous on the margins; glumes strongly hispid-scabrous on the 



keels/ 2. S. cyxosuroides. 



Blades glabrous throughout or minutely scabrous on the margins; glumes 

 glabrous or usually softly hispidulous or ciliate on the keels. 

 Inflorescence dense and spikelike, the spikes closely imbricate; the spike- 

 lets mostly somewhat curved, giving a slightly twisted effect; blades 



mostly comparatively short 3. S. leiaxtha. 



Inflorescence less dense, the spikes more slender, less crowded, the spike- 

 lets not curved, the inflorescence with no suggestion of a twist. 



4. S. alterxiflora. 



Blaaes less than 5 mm wide (rarely more in S. gracilis); ir volute (sometimes flat 



in S. gracilis); plants mostly slender and less than 1 m tall (taller in S. bakeri). 



Inflorescence dense, cylindric; spikes numerous 5. S. spartixae. 



Inflorescence not cylindric; spikes not more than 10, usually fewer. 



Creeping rnizomes absent (see also S. patens var. caespitosa) ; plants in large 

 hard tufts with tall culms (1.5 to 2 m) and long slender blaaes. 



6. S. bakeri. 

 Creeping rhizomes present (except in S. patens var. caespitosa) ; plants usually 

 less than 1 m tall. 

 Spikelets crowded, the spikes mostly thick, erect; Western States. 



7. S. GRACILIS. 



Spikelets less crowded, the spikes relatively slender, ascending; Atlantic 

 seacoast 8. S. patexs. 



1. Spartina pectinata Link. Prairie cordgrass. (Fig. 1038.) 

 Culms 1 to 2 m tall, firm or wiry; blades elongate, flat when 

 fresh, soon involute in drying, as much as 1.5 cm wide, very scabrous 

 on the margins; spikes mostly 10 to 20, sometimes fewer or as many 

 as 30, mostly 4 to 8 cm long, ascending, sometimes appressed, rarely 

 spreading, on rather slender peduncles; glumes hispid-scabrous on 

 the keel, the first acuminate or short-awned, about as long as the 

 floret, the second exceeding the floret, tapering into an awn as much 

 as 7 mm long; lemma glabrous except the scabrous keel, 7 to 9 mm 

 long, the apex with two rounded teeth; palea usually a little longer 

 than the lemma. % (S. michauiiana Hitchc!) — Fresh-water 

 marshes, Newfoundland and Quebec to eastern Washington and 

 Oregon, south to North Carolina, Kentucky, Illinois, Arkansas, 

 Texas, and New Mexico; in the Eastern States extending into brackish 

 marshes along the coast (fig. 1039). 



2. Spartina cynosuroides (L.) Roth. Big cordgrass. (Fig. 1040.) 

 Culms 1 to 3 m tall, stout, the base sometimes as much as 2 cm thick; 

 blades flat, 1 to 2.5 cm wide, very scabrous on the margins; spikes 



