COMMON HED CLOVER 233 



clover is liable to be uprooted by the alternate 

 freezing and thawing, and on sandy lands it suf- 

 fers from drought. Like alfalfa, the soil must be 

 either rich in lime, or this substance must be 

 applied, for it is a heavy feeder on lime, as well 

 as on the other mineral constituents. The very 

 beneficial effects that were observed from the 

 former use of gypsum, when it was thought that 

 plaster or gypsum was a specific fertilizer for 

 clover in the eastern states, is now considered 

 to be due to the power that gj T psum possesses 

 of setting free the dormant potash of the soil. 

 Therefore, on old soils from which the potash has 

 been to some extent exhausted, the element potas- 

 sium should be applied in considerable excess. The 

 very beneficial effect of w T ood ashes, following 

 the use of gypsum, also verifies this conclusion, 

 as ashes is rich in both of the constituents, potash 

 and lime. 



As clover is a legume, it is not usually bene- 

 fited by the addition of nitrogenous manures, 

 except in the early stages of growth. On soils 

 not well supplied with vegetable matter, manures 

 are very beneficial, primarily in correcting the 

 deficiencies, and in providing a more favorable 

 medium for the development of the specific bac- 

 teria. The size of the crop will be measured to 

 some extent, also, by the abundance of mineral 

 elements, thus enabling the plant to employ to 



