HOW TO KNOW THE GRASSES 



11a. Plants with rhizomes; spikelets disarticulating below the glumes, 

 falling whole 12 



lib. Plants tufted, lacking rhizomes; spikelets disarticulating above the 

 glumes, the floret dropping. Fig. 256. 



TUMBLEGRASS Schedonnardus paniculatus (Nutt.) Trel. 



Perennial; tufted; plants 20 — 40 cm. tall, 

 with short, crowded basal leaves. Most of 

 the height of the plant is made up of the 

 skeleton-like panicle of very slender spikes. 

 The main axis of the inflorescence is some- 

 what spiral. The whole panicle breaks from 

 the plant when ripe and rolls with the wind, 

 thereby distributing the seed. This is a grass 

 of poor, dry soil, especially on overgrazed 

 or disturbed areas. Forage value very low. 

 June — August. 



Figure 256 



12a. Leaf blades flat when fresh, 4 — 25 mm. wide 



13 



12b. Leaf blades rolled, 2 mm. or less wide. Fig. 257. 



SALT-MARSH GRASS Spartina patens (Ait.) Muhl. 



13 



Figure 257 



Perennial; spreading by slender, scaly 

 rhizomes, forming large colonies in coastal 

 salt marshes along the Atlantic and Gulf 

 coasts. Culms up to 1 m. tall, usually 

 shorter. This grass is tough and harsh, 

 but is frequently harvested for hay, which 

 is used as packing material. The plants 

 are valuable as land-builders along the 

 coast, trapping and holding the tidal mud. 

 July — September. 



Spartina gracilis Trin. (ALXALI CORD- 

 GRASS) is similar, but is found on alkaU 

 or sahy flats in the interior of the United 

 States, from the Dakotas to Kansas, west- 

 ward to Washington and CaUfomia. 



136 



