PHOSPHATIC MANURES 138 



not appreciated by stock, which will hardly 

 eat it, at least during summer, if better 

 herbage is to be obtained. It is, to a large 

 extent, suppressed by the luxuriant growth 

 of clover which follows the use of phosphatie 

 manure ; but when the clover is in its turn 

 partially displaced, the grasses that follow 

 are generally Poas, Fescues, Fox-tail, Yellow 

 Oat Grass, and Cock's-foot. While grasses 

 become more conspicuous about the fourth 

 year, and tend to increase in subsequent 

 years, White Clover does not by any means 

 completely disappear, although it is usually 

 much less abundant than in the earlier 

 stages of the improvement. 



The cause of the reduction in quantity of 

 the clover would appear to be associated 

 in some way with the phenomenon that is 

 known as Clover Sickness, which, as is well 

 known, prevents the growth of Red Clover, 

 except at considerable intervals, on many 

 classes of tillage land. While the causes of 

 Clover Sickness are not fully understood, it 

 would appear to be likely that some re- 

 stricting factor is induced to assert itself in 

 consequence of the too frequent or over- 

 luxuriant growth of clover ; and one way 

 by which the trouble may be overcome is 

 to desist from the attempt to cultivate Red 



