THE EARTH'S BOUNTY 



Dakota Station also examined the roots of one- 

 and two-year-old plants of Bromus inermis, 

 and found that at one year old the roots had 

 attained a depth of over 4 feet and formed a 

 good sod, while the roots of the two-year-old 

 grass had reached a depth of at least 5 l /2 feet. 

 In comparing the root systems of native 

 prairie grasses, timothy roots, and the roots 

 of Bromus inermis, it was found that the 

 roots of the native prairie grasses did not 

 make as heavy a sod as the cultivated ones, and 

 that the roots examined reached less than 3 

 feet in depth. In later work a brome grass 

 specimen taken from a three-year-old sod 

 showed the densest rooting of all samples of 

 cereal and forage crops. Native slender 

 wheat grass, also from a three-year-old sod, 

 did not have the strong root growth of the 

 brome grass, although its root system was 

 heavier than that of any other crop studied. 

 The Kansas Station also found that the largest 

 growth of fibrous roots in the surface soil was 

 made by the perennial grasses as compared 



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