40 RESEEDING WESTERN GRAZING LANDS 



find other methods and implements than those upon wliich the 

 farmer ordinarily relies. 



PLANT INTRODUCTION ON ARID LANDS 



Many attempts have been made to grow cultivated plants on 

 the more arid, sparsely vegetated range. That little progress 

 has been made in reseeding such lands is evident from several 

 carefully conducted tests. 



Tests in Southern Arizona. — The most extensive tests in 

 seeding native forage plants were conducted by Griffiths/ 

 Thornber," and Wooton,' between 1900 and 1916. 



Griffiths's studies were confined to trials with introduced and 

 native forage plants upon the mesa lands, where not less than 

 200 plant species were tested in a fenced pasture. The seeding 

 was done in both spring and fall. In some tests the ground was 

 worked up sufficiently to kill a goodly portion of the native 

 vegetation. Notwithstanding these carefully conducted tests 

 and the special soil treatment, most of the introduced plants 

 failed even to gain a foothold. Only one introduced species, 

 namely, allilaria (Erodium cicutarium), gave results, and those 

 were of limited practical value. Griffiths concludes: 



The net economic results of all this foreign introduction has been practically 

 nil. Most of the species in our experience have never come up, and the few 

 things that did make any growth usually died before seed was produced. 



Thornber, experimenting on a range reserve near Tucson, 

 Arizona, after finding that experimental seedings failed on the 

 drier lands, attempted a series of experiments on similar areas, 

 some of which were irrigated. The increased water supply was 

 procured by the construction of dams, by means of which flood 

 water was conserved. Such valuable native species as blue 

 grama {Bouteloua gracilis) and hairy grama {B. hirsuta) pro- 

 duced a fairly good cover where the lands were amply watered. 



^ Griffiths, David, "A Protected Stock Range in Arizona." U. S. Dept. of 

 Agr., Bur. of Plant Ind., Bui. 177, p. 12, 1910. 



2 Thornber, J. J., "The Grazing Ranges of .\rizona." Arizona Agr. E.xp. Sta. 

 Bui. 65, p. 312, 1910. 



^ Wooton, E. O., "Carrying Capacity of Grazing Ranges in Southern Arizona." 

 U. S. Dept. of Agr. Bui. 367, p. 38, 1916. 



