182 



Nature-Study Agriculture 



Keeping 

 manure 

 sheltered 

 and wetting 

 it 



The effects 

 of exposure 

 to rain and 

 air 



animals tread on the manure, which is mixed with clean 

 straw used as bedding, and so pack it that air does not 

 enter freely. Keeping the air out prevents chemical 

 changes that would cause much of the strength to escape 

 in the form of gases. The bottom of the stall is tamped 

 or cemented to prevent leakage. 



Another method of storing manure is to pile it in a 

 heap under shelter, keeping it so wet that not much air 

 can penetrate it. Care must be taken not to put on 

 so much water that some of it. will drain away, carrying 

 off dissolved plant-food materials. 



Figure 139 shows a wasteful method of keeping manure 



that is all too common. 

 The manure" is thrown 

 in a loose heap, not only 

 unsheltered, but even 

 under the drip of the 

 eaves. A great deal of 

 nitrogenous material, 

 potash, and phosphate 

 are thus sure to be dis- 

 solved from the manure 

 and washed away by the 

 rain (Fig. 140 and Exp. 

 7 ). Also, the manure 

 being alternately wet 

 and dry, the air acts on 

 U.S.D.A. ft chemically so as to 



FiG. 139. The manure in this heap loses . . , 



most of its value through leaching, and the CaUSC quantities OI nitro- 



boards against which it is piled rot; flies (TQY\. to CSCaDC as *as 



breed in the manure, and mosquitoes 



breed in the pool. This aCCOUntS for the 



