HOW TO KNOW THE GRASSES 



the Southwest; found throughout the tropics of both Old and New 

 World. June — September. 



Heteropogon melanocarpus (Ell.) Benth. has staminate spikelets with 

 glabrous glumes, a row of glandular spots running down the middle 

 of the glume. Southeastern states and Arizona. 



lib. Awned spikelets falling, awnless ones remaining on the persistent 

 rachis of the raceme. Fig. 345. 



CRINKLE AWN Trachypogon secundus (Presl) Scribn. 



Perermial; tufted; 60 — 120 cm. tall; herbage 

 nearly smooth but the nodes bearing a circle of 

 stiff, erect hairs. The erect slender raceme is 

 10 — 20 cm. long. The rachis remains whole with 

 the short-pedicellate or sessile staminate spike- 

 lets attached to it. The longer-pedicellate per- 

 fect spikelets break from the rachis with their 

 hairy, rigid pedicels attached. The perfect spike- 

 let looks very much like the floret of some spe- 

 cies of Stipa. The lemma is 6 — 8 mm. long, with 

 a bent and twisted awn 3 — 6 cm. long. Rocky 

 dry hills. May — October. 



Figure 345 



12a. Racemes several to many on each pedimcle 13 



12b. Racemes one on each peduncle. Fig. 346. 



LITTLE BLUESTEM Andropogon scoparius Michx. 



Perennial; tufted; plants green or red- 

 dish, 50 — 150 cm. tall; foUage smooth or 

 hairy. The racemes are borne on slender 

 peduncles from the axils of the sheaths 

 and the tips of the culms. The rachis 

 joints and pedicels are strongly hairy. 

 Little bluestem is characteristically a plant 

 of dry prairies and plains, but occurs to 

 some extent over nearly the entire United 

 States. Prairies, old fields, rocky slopes 

 and open woods. Little bluestem furnishes 

 much grazing in the Middle West and 

 West, especially for cattle and horses. 

 August — October. 



Figure 346 



Nine other species, similar in having only one raceme on each 

 peduncle, occur in the southern United States, but are much rarer. 

 13a. Stalked spikelet sterile, rediiced to a small rudiment or nearly 

 absent; racemes feathery, white 14 



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