526 NxVTURE AND PROPERTIES OF SOILS 



supply of manure is usually limited in diversified farming, to 

 decrease the amounts at each spreading and cover a greater 

 acreage. Thus, instead of adding 20 tons to the acre, 10 tons 

 may be applied and twice the area covered. Applications 

 could then be made oftener and a larger and quicker net 

 return realized for each ton of manure. With manure, as 

 with any fertilizer, the yield to the acre is not so important 

 as the crop increase for a given increment of manure added. 

 The influence of rate of application on increased yield to a 

 ton of manure is shown by the Ohio ^ experiments over eight- 

 een years in a three-year rotation of wheat, clover and pota- 

 toes, the manure being placed on the wheat. 



Table CXVIII 



increased yield to the ton when manure is applied in 

 different amounts. ohio experiment station. 



Rate 



Wheat 

 (bus.) 



Glover 

 (lbs.) 



Potatoes 

 (bus.) 



4 tons to the acre. . . 



8 tons to the acre 



16 tons to the acre 



1.34 

 .94 

 .70 



177 



150 



99 



3.81 

 2.79 

 2.76 



Not only is the increased efficiency from the smaller appli- 

 cation apparent, but a greater recovery of the manurial fer- 

 tility in the crops also results. The Ohio experiments show 

 that in the first rotation after the manure is applied, a 25 to 

 30 per cent, higher recovery may be expected from the 8 tons 

 treatment than from the 16 tons. 



Evenness of application and fineness of division are greatly 

 facilitated by the use of a manure-spreader. This also makes 

 possible the uniform application of small amounts of manure, 



* Thorne, C. E., and others, Flans and Summary Talles of the JExperi- 



ments at the Central Farm; Ohio Agr. Exp. Sta., Circ. 120, p. 108, 

 1912. ^ I , , i^ , 



