66 Journal of Agricultural Research voi. xix, No. 2 



When the vegetation is considered from the standpoint of grazing, 

 only a very few species are important factors in the total amount of 

 forage annually produced. Sampson (6) has discussed this point more 

 fully. In this region, Bouteloua gracilis and Siipa comata are the most 

 important species, both on account of their total forage production and 

 their value as grazing grasses. 



The value of a given species for grazing purposes depends upon (i) its 

 abundance, (2) whether it is relished by stock, (3) its length of growing 

 season, (4) its ability to withstand trampling and to recover readily from 

 grazing, and (5) its adaptation to drought conditions. According to 

 these requirements, Bouteloxia gracilis would take first rank and Stipa 

 comata would be second in importance. 



A plant may be of importance in relation to grazing because of its 

 abundance, whether it is or is not of grazing value. If it is a valuable 

 grazing species it is of primary importance, and if it is of minor grazing 

 value it is of importance because it occupies ground surface that might 

 otherwise support a more valuable species. On the other hand, a species 

 may be greatly relished by stock, as Andropogon furcatus at Mandan, 

 but occur in such limited areas that it is unimportant in the total amount 

 of forage annually produced. In pastures where this grass occurs it is 

 cropped close to the ground throughout the season, as illustrated in 

 Plate 13, A. 



Bouteloua gracilis is grazed with avidity at all times of the year. It 

 cures well on the ground without great loss of its nutritive value, and late 

 in the fall cattle eat it in preference to any other grass. Although Stipa 

 comata has the disadvantage, for a short period, of its sharp needles, it is 

 so much more abundant than other species, except B. gracilis, that it 

 enters largely into the feed of grazing animals. It is the first grass to 

 produce green shoots in the spring, and it usually produces more growth 

 late in the fall than do other species. 



A grass that is similar in appearance and often confused with Bouteloua, 

 gracilis is Bulhilis dactyioides , or buffalo grass. It has a better reputa- 

 tion for grazing and is more widely known by a popular name than any 

 other single species of grass in the Great Plains. However, out of 

 several thousand acres of native vegetation surrounding the field station, 

 there are less than 5 acres of the true buffalo grass. On a trip over 

 western North Dakota in the summer of 191 6, the author found this grass 

 in only a few small areas. Blue grama {Bouteloua gracilis) is and always 

 has been called buffalo grass by the people in the Great Plains area. 

 This misnomer has been and is so universal that it is difficult to obtain 

 reliable information concerning the abundance and importance of 

 buffalo and blue grama grasses for grazing in the early history of the range. 

 However, at present the true buffalo grass occurs only in small amounts 

 in this region and in western North Dakota, where it is evident it never 



