HOW TO KNOW THE GRASSES 



HOW TO RECOGNIZE THE TRIBES OF GRASSES 



HE common grasses of the United States are grouped into 

 thirteen tribes, or subdivisions of the family. With a 

 Httle practice, it is usually possible to determine the 

 tribe to which a given grass belongs very quickly, 

 thereby making it unnecessary to go through a portion 

 of the key. The following summaries of the characteris- 

 tics of the different tribes should help you to recognize 

 them. 



Subfamily FESTUCOIDEAE. Spikelets with one to numerous florets; 

 sterile florets, if present, usually at the tip of the spikelet; spikelets 

 laterally compressed or round in cross section; disarticulation usually 

 above the glumes. 



Tribe I. BAMBUSEAE. Tall plants, with woody perennial cuhns. Spike- 

 lets rarely present. Page 15. 



Tribe II. FESTUCEAE. Spikelets with several ^ \ ^^ 



to many florets; glumes not reaching the tip ^^ ,\J^ 



of the lowermost floret; disarticulation usually 

 above the glumes; inflorescence a panicle. 

 Fig. 11. Pages 23-84. 



Figure 1 1 



Tribe III. HORDEAE. Inflorescence a single 

 terminal spike, with spikelets in rows on op- 

 posite sides of the rachis. Spikelets with one 

 to several florets, usually disarticulating 

 above the glumes. Fig. 12. Pages 85-94. 



Figure 12 



Tribe IV. AVENEAE. Spikelets similar to 

 those of the Festuceae, but with much 

 enlarged glumes, usually covering the 

 entire spikelet. Disarticulation above 

 or below the glumes; inflorescence a 

 panicle. Fig. 13. Pages 95-101. 





Figure 13 



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