462 



STATE BOARD OF AGRICULTURE. 



in it results favorably, increasing the root, leaf and stem development, 

 aids in grain formation and shortens the growing period. 



The effects on the soil are beneficial rather than harmful and its 

 judicious use is a business-like procedure. 



The most profitable amount to apply is governed by the nature of the 

 soil, carrier used, as well as somewhat by the prices paid for the fertilizer 

 and received for the crop grown. 



The active form usually should be applied to the cash crops in the 

 rotation and the other if used when sod, meadow or other crop residues 

 are to be turned under. 



Figiiro 21. — Swppf rlovf>r responds vigorously to liino and iiliospliorus. On some of tho liglil 

 soils potash is needofl. This clover is gr(>wing on the same soil as the rye shown in Figure 

 15. The result of lime and acid phosphate. It will solve the nitrogen and humus problem. 



Phosphate fertilizers may be applied in several ways, but it is usually 

 advisable to utilize a fertilizer distributor. 



The phosphorus content of barnyard maiiuie is relatively low in com- 

 parison with nitrogen and potassium and the reinforcement of it with one 

 of the carriers usually is desirable. 



As nearly as can be estimated about 22,900,000 pounds of phosphorus 

 are lost from Michigan soils annually. 



Analyses of samples of soil from fields long under cultivation and from 

 uncropped adjacent land show that the change in the phosphorus content 

 of the soil is governed by the system of farming followed. In several 

 instances as much as forty per cent of phosphorus was found to have been 

 removed from the surface soil, in others twenty per cent, and in still 

 others little if any changes have taken place. 



