EXPP^RIMENT STATION BULLETINS. 



44? 



either caustic lime or wood aslies aiul if mixed with nitrate of soda the 

 mixture should be applied immediately. 



Where to Apply. It is usually advisable to fertilize the rotation. 

 Phosphates are fixed or held by the soil until utilized by growing plants, 

 although when acid phosphate is applied to light sands it may be washed 

 <lo\vnward to some extent. Tliis means that crops following in the rota- 

 lidii are benefited l»y phosphorus left by previous crops. It is generally 

 considered tliat about two-thirds the cost of the application of acid phos- 

 l)hate should be charged to the first crop and the remainder to those that 

 follow in the rotation. In case of the floats these figures do not apply 

 and it is usually the practice to add them to the clover or other sod before 

 plowing and repeat the application in from four to six years, depending 

 upon the size of the application and the crops grown. It is advisable to 

 apply the bone meal or acid phosphate to the grain crops in the rotation 

 as illustrated by figures 6 and 7. In several sections it is becoming more 



Kig'ure 5. — Oats growing on Van Buren Co. sandy soil. On the left 1000 pounds of rock 

 phuspliate per acre were applied to corn before the oats. On the right liOOO pounds were 

 added. It pays to use the rock pliosphate freely. 



and more difficult to obtain suitable stands of clover with small grains, 

 as a result proper rotation of crops becomes difficult. It is doubtless 

 true that* the lack of both lime and phosphorus in the soil accounts in a 

 large measure for this undesirable condition and judicious applications 

 of these result favorably as illustrated by figure 8. 



HoiD to Apply. There are several methods of applying these fertilizers. 

 Kaw rock phosphate is applied by means of a lime and pliosphate dis- 

 tributor, fertilizer drill, or with the manure spreader when the manure 

 is applied to the soil. Bone meal may be I)road-casted and incorporated 

 with the soil when the seed bed is prepared, distributed by means of a 

 fertilizer distributor or attachment to the grain drill. 



