GRAMINEAE 



completely by Ephed ra viridis and Nuhlenbergia pun gens , was once 

 covered by other plants. At present, however, much of the wind- 

 blown sandy area is so completely taken by these two species that 

 a definite statement regarding the original vegetation seems con- 

 jectural. This species likes the drifting sands where the move- 

 ment is not too severe and since it forms dense clumps, spreads by 

 creeping rhizomes and is quite unpalatable even to sheep and goats. 

 It is an ideal sand binder. Our knowledge of. its propagation is 

 nil at present and reports must await the results of observational 

 planting which the Nursery Section or the Navajo agronomists can 

 make in the future, Vihile it seeds abundantly, the only way seed 

 can be conveniently collected is with hand strippers because of 

 the extreme roughness of sites on which it grows. Incidentally, 

 it should be mentioned that this is ono of our riost handsome 

 grasses well worthy of trial as an ornamental. This species reaches 

 its maximum development in northern Arizona and northern New Mexico 

 but extends as far north as Y/yoming and South Dakota in the Rocky 

 Mountains. 



* Muhlenbcrg ia ropens, Creeping I'uhly, Among the plants which 

 have taken advantage of the severe overgrazing of the range in some 

 of the southwestern mountains, is M, ropens. It is very low in 

 palatability and as it spreads raplcTly by creeping rhizomes and 

 forms dense carpets, it is an ideal erosion control plant. Like 

 all other plants, it is limited in its usefulness by the site 

 requirements* It, however, covers hundreds of acres of the gentle 

 slopes in such mountains as the Capitans of New Mexico and the Dos 

 Cabezos of Arizona. It has a persistent habit of closing in on 

 small water courses started by cow trails and old wagon or auto 

 ruts. On gentle slopes and in the bottoms of swales it is an al- 

 most perfect desilter, ^ little of it planted on the nursery at 

 Tucson has grown vigorously and spread rapidly by rhizomes but not 

 by seed. On the range it is not easy to locate good seed. A good 

 collection, however, was made in 1337, Since it is very low it is 

 best collected by means of lawn mowers with the usual hopper attach- 

 ment. Its natural distribution is western Texas, New Mexico and 

 Arizona. It doubtless is widespread in northern Chihuahua also but 

 thus far it has been reported from but one locality. 



*Muh 1 enb erg i a rigens. Deer Grass, as this one is often cal- 

 led, is confined to rather moist places usually in the beds of 

 rocky washes and to steep usually north-facing slopes in the extreme 

 southwest. It has rather coarse, stiffly erect stems from a tough 

 hard rhizomatous base which is calculated to held its ground even 

 in severe floods. In fact the clumps anchor themselves sc tightly 

 to the rocks that viator merely bends the culms downstream after 



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