NATIVE GRASSES OF NORTHERN MEXICO. 97 



Heteropogon contortus, R. & S. This is probably the most 

 abundant grass of dry hills of igneous rock thinly covered with 

 soil. It grows in tall, narrow clumps, and is a perennial with 

 numerous leafy branches. Stock show a preference for other 

 grasses if such are to be found. The hay on sale in Chihuahua 

 last spring seemed to be mainly composed of this plant, usually 

 dead when gathered, and blanched by winter weather. During 

 autumn I found its seeds a nuisance. Their long bearded and 

 twisted awns sent the slender and rough seeds into my clothing, 

 and often into my flesh. Sheep, goats, and even donkeys must 

 find these seeds a terrible annoyance. 



Andropoyon Itirtiflorus, Kth., is a fine, soft, leafy plant, grow- 

 ing in dense clumps, but apparently confined to hedges, etc. 



Andropogon saccliaroides, Sw., grows in clumps three or four 

 feet tall. In valleys, and the moister depressions of the plains, 

 this is a grass of some importance. 



Some ten species or more of Arixtida are mostly bunch grasses 

 of hills and mountains, of average frequency in such situations, 

 and of full average quality, contribiiting largely toward the 

 upland pastures. 



There are two new species cf Stipa also, tall and tender plants, 

 excellent for forage but not abundant. 



There are many species of Mulilenbergia of more or less value. 

 M. Texana, Thurber, is the mesquite grass of our southwest, and 

 one of the most valuable species of those regions, common over 

 mesas and hills. It is such a favorite with animals that it is 

 exterminated except when growing under the protection of 

 thorny shrubs, usually mesquite bushes (species of Prosopis and 

 Acacia). Its leaves are short and scanty, but its branching, 

 perennial, wiry stems are nutritious, and at all seasons furnish 

 forage which is greatly relishel by all kinds of stock. In Ari- 

 zona the Indians bring it during winter and spring long distances 



into the towns to sell, the men tying the bundles behind and 

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