Nov. 



W/fcaf and its CuU'ivation. 



699 



The residual value 

 of various applications 

 should be carefully mea- 

 sured by their effect on 

 the resultant stubble and 

 pasture. Unfortunately, 

 the residu.d value of 

 various heavy and light 

 dressings of super, on 

 the sheep carrying capa- 

 city of the pasture has 

 not been the subject of 

 systematic and continued 

 experiment in this State, 

 and there is no local data 

 as a guide. 



In any case it is well 

 to remember that, even 

 if the value of the extra 

 yield obtained from 

 heavy dressings merely 

 covers the increased cost 

 of the manure, it will 

 pay to use the heavy 

 dressing, because the 

 soil is being enriched in 

 phosphoric acid without 

 extra cost. 



It may be thought 

 that, if more soluble 

 phosphates are applied 

 than are really necessary 

 for a wheat crop, the 

 excess is lost for succeed- 

 ing crops. Such, how- 

 ever, is not the case. 

 Phosphates, unlike ni- 

 trates, are not generally 

 found in the drainage 

 waters. They become 

 fixed in the soil shortly 

 after their application. 

 As explained above, 

 soluble phosphates, when 

 applied to the soil, be- 

 come dissolved and inti- 

 mately mixed with the 

 soil particles, and then 

 rapidly imdergo conver- 

 sion into less soluble 

 forms. In tliis manner 



