134 AGRICULTURE 



Clover on the particular field until the land 

 has had a " rest." Many leguminous plants 

 are subject to some such " sickness," "and 

 as all must have healthy colonies of bacteria 

 on their roots for successful growth, the 

 conclusion would appear to be justified that 

 the sickness of the plant is closely associated 

 with sickness amongst the bacteria. What- 

 ever the reason, there is no doubt'*as~to the 

 fact that White Clover, which may have 

 been very abundant two or three years after 

 phosphates were applied, becomes com- 

 paratively scarce. But after the clover 

 has remained on a lower level of productive- 

 ness for some years, it generally responds to 

 a repeated dressing of basic slag, although 

 not to the same extent as in the first instance ; 

 so that the most rational method of treating 

 such land would appear to be to apply a 

 substantial dressing (7-10 cwt. per acre) of 

 a phosphatic manure to begin with, and to 

 supplement this after an interval of five or 

 six years with a smaller dressing (4-6 cwt. 

 per acre). Although superphosphate of lime 

 has a stimulating influence upon clover, it 

 is rarely that one sees quite such striking 

 results from the use of this substance as 

 those which follow the application of basic 

 slag. 



