PAEM MANUKB 527 



even as low as 5 or 6 tons to the aere. It is impossible to 

 spread so small an amount by hand and obtain an even dis- 

 tribution. Moreover, a spreader lessens the labor and more 

 than doubles the amount of manure one man can apply a day. 

 When any considerable quantity of manure is to be handled, 

 a manure-spreader will pay for itself in a season or two at the 

 most. 



"Whether manure should be plowed under or not depends 

 largely on the crop on which it is used. On timothy it is 

 spread as a top dressing. Ordinarily, however, it is plowed 

 under. This is particularly necessary if the manure is long, 

 coarse, and not well-rotted. It should not be turned under 

 so deep, however, as to prevent ready decay. If manure is 

 fine and well decomposed, it may be harrowed into the surface 

 soil. The method employed depends on the crop, the soil, and 

 the condition of the manure. The amount to be applied va- 

 ries considerably. Eight tons to the acre would be a light 

 dressing, 15 tons a medium dressing, and 25 tons heavy for 

 an ordinary soil. In trucking land, however, as high as 50 

 or 100 tons are often used. 



303. Reinforcement of manure, — The reinforcement of 

 farm manure is designed to accomplish two things in the han- 

 dling of this product: (1) checking loss due to leaching and 

 decomposition, and (2) balancing the manure and rendering 

 its agricultural value higher. Four chemicals may be used 

 in this reinforcement: gypsum (CaS04), kainit (mostly 

 K2SO4), acid phosphate (CaH4(P04)2 + C,aS04), and floats 

 (raw rock phosphate, Ca3(P0j2)- 



Gypsum and kainit are supposed to react with the ammonia 

 of the manure, changing it to ammonium sulfate, a stable 

 compound. As gypsum is rather insoluble, its action is prob- 

 ably slow. It may be applied either in the stable or on the 

 manure pile, usually at the rate of 100 pounds to the ton. 

 It has no balancing effect. Kainit is soluble and because of 

 its caustic tendencies should not come into contact with the 



