COMMON RED CLOVER 233 
clover is lable 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 gypsum 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 wood 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 
