18 



BULLETIX 1087, U. S, DEPAHTMEXT OF AGPJCULTLTIE. 



Most of the seed that is placed on the market is produced in Mon- 

 tana and the Black Hills region of South Dakota. The root systems 

 of this alfalfa are fairly uniform and intermediate between the root 

 sj'stem characteristic of southern-grown conunon alfalfa and that of 

 the hardier varieties, such as Turkestan and Grimm. The taproot is 

 quite distinct and branch roots are most prominent at 1^ to 4 inches 

 below the crown. This is somewhat nearer the surface than is charac- 

 teristic of the southern-grown strains and almost identical with the 

 Turkestan and Grimm. In number and prominence of branch roots, 

 the northern-grown common alfalfa exceeds the southern grown, 

 but does not equal the Turkestan and Grimm. The distinguishing 



Fig. 1.3. — Root systems of northern-grown common alfalfa plants, the 



season. 



growth of one 



differences in these respects, however, are usually so slight that they 

 can be noted only by examining many plants. (Fig. 13.) 



TURKESTAN ALFALFA. 



Strains of Turkestan " alfalfa have been under test for a number 

 of years in the nortliern Great Plains region, and certain introduc- 

 tions have proved hardy and quite productive. They are character- 

 ized by broad, deep-set crowns and more numerous crown branches 

 than the common and nonhardy alfalfas. The taproots are relatively 

 shorter, more tapering, and less distinct than in common, Peruvian, 

 and Poona. The diameter of the taproot somewhat exceeds that of 

 the nonhardy alfalfas studied, but as measurements show, it is some- 

 what less in plants of one season's growth than in the Grimm alfalfa. 



* The root systems of plants of Turkestan alfalfa studied at Redfield were from plats 

 sown with seed that was the result of several seed generations in the northern Great 

 riains region. The original seed was of S. P. I. Xo. 991, which was collected under the 

 direction of the IT. S. Department of Agriculture at Tashkend. Turkestan, in 1898. 



