12 



BULLETIN 201, U. S. DEPARTMENT OP AGRICULTURE. 



valuable grasses have been exterminated, it constitutes the main feed, aside from that 

 furnished by the shrubs. (PL III, fig. 2.) 



No. 9618 was collected in the Santa Rita Mountains of Arizona, September 22, 1908. 

 The sample was mature, but only a few spikes had fallen off. It was cut close to the 

 ground. Its percentage of moisture was 2.44. Other constituents (on a water-free 

 basis) were as follows: Ash, 6.84; ether extract, 2.12; crude fiber, 35.11; nitrogen- 

 free extract, 46.96; protein, 8.97; pentosans, 23.16. 



BOUTELOUA BURKH Scribn. 



Bouteloua burkii, a species of grama, is one of the most abundant of the pasture grasses 

 of central to southern Texas. It is a perennial, seldom growing over 10 inches high, 

 and usually only about 6 inches, but it produces an abundance of root leaves and fur- 

 nishes a very large percentage of the forage of the native pastures of the region. It 

 never gets large enough to be considered as a hay crop. Like the vast majority of 

 gramas its seed habits render it useless for cultivation. 



No. 8398 was collected near Green, Tex., August 14, 1906. The sample was overripe, 

 the seed having all fallen, and half of the plant was dead and dry. It was cut close to 

 the ground. Its percentage of moisture was 6.81. Other constituents (on a water-free 

 basis) were as follows: Ash, 12.89; ether extract, 1.82; crude fiber, 30.54; nitrogen- 

 free extract, 46.70; protein, 8.05; pentosans, 22.13. 



BOUTELOUA CURTIPENDULA (Michx.) Torr. 



Bouteloua curtipendula, the side-oat grama, as it is popularly called, is the most 

 promising of the gramas for cultivation. It makes a taller, ranker growth than any of 

 the other species, but like the others has poor seed habits for an agricultural grass. 

 It has a wider distribution in the United States than any of the other gramas except, 

 possibly, B. hirsuta, which is of much less value. Some efforts have been made to 

 domesticate it, and this species is one that was always included in the tests made 

 during the grass-garden period of experimentation of 12 to 15 years ago. A stand 

 of it is not difficult to obtain from seed, but in all cases of cultivation whole spikes, 

 as they were stripped from the plant, were invariably sown or drilled in. The 

 separation of pure, clean seed is not to be considered. 



The species is conspicuous and is an important pasture plant mainly upon the 

 rougher portions of the Plains region . In southern Arizona it inhabits similar situations 

 at altitudes mainly between 3,000 and 5,000 feet.. However, when sown and fur- 

 nished sufficient water, it thrives upon the desert mesas at 2,000 feet or less. The con- 

 trolling factor in its growth is moisture. When this is properly supplied, it adapts 

 itself to almost all other conditions. 



No. 8589 was collected on the north slope of the Santa Rita Mountains of Arizona 

 September 27, 1906. The straw in this sample was ripe and dry; some of the seed had 

 fallen. 



Material analyzed. 



Percent- 

 age of 

 moisture. 



Water-free basis (per cent). 



Ash. 



Ether 

 extract. 



Crude 

 fiber. 



Nitrogen- 

 free ex- 

 tract. 



Protein. 



Pen- 

 tosans. 



Our sample No. 8589 



4.60 



8.31 

 9.76 



1.59 

 1.85 



32.49 

 37.76 



53.28 

 45.05 



4.33 

 5.58 



25.88 

















9.63 



1.94 



32.86 



49.23 



6.34 











1 Colorado Bui. 8, p. 11; Iowa Bui. 56, p. 461; New Mexico Bui. 17, p. 36; Wyoming Bui. 87, p. 28. 

 BOUTELOUA ERIOPODA Torr. 



Bouteloua eriopoda, the black grama of New Mexico and the woolly-foot of other regions, 

 is a species of varying importance from Colorado south and from Texas to California. 

 Over the greater portion of its range it is strictly a pasture grass, but in portions of south- 

 ern New Mexico it is frequently cut for hay in almost pure stands from the upper, open 



