HOW TO KNOW THE GRASSES 



TRIBE II. FESTUCEAE 



la. Spikelets all similar in appearance (rarely unisexual) 2 



lb. Spikelets of 2 diiierent kinds 8 



2a. Lemmas undivided or with not more than 3 awns at the tips .... 3 



2b. Lemmas bearing at the tip 9 or more awns, which are feathery on 

 the lower half. Fig. 41. 



PAPPUS GRASS 



Enneapogon desvauxii Beauv. 



Figure 41 



Perennial; tufted; culms 20 — 40 cm. 

 long; panicles spikelike. Leaf blades 

 threadlike, about 1 mm. wide. The 

 lower sheaths are somewhat swollen, 

 and contain cleistogamous spikelets 

 which have nearly awnless lemmas. 

 Several related species in the genus 

 PappophoTum lack the feathery hairs 

 on the awns. Dry desert hills and 

 plains, from western Texas to Ari- 

 zona and southward. Forage value 

 low. September — October. Also 

 called Pappophorum wiightii. 



3a. Rachilla joints or backs of the lemmas bearing long straight hairs 

 which give the spikelets a silky appearance; tall grasses, the culms 

 1—4 m. high 4 



3b. Rachillas and lemmas not covered with hairs which cover the 

 spikelet; (lemmas sometimes hairy on nerves or callus); plants 

 usually 1.5 m. or less tall 5 



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