METHODS OF USE 267 



be discouraged, for they are not only expensive, but by 

 interfering with the activity of bacteria in manure destroy 

 one of its most valuable functions, namely, that of supplying 

 microorganisms to the soil. 



6. Lime Should Never be Used. — In this connection it 

 must be emphasized that for the preservation of nitrogen 

 or absorption of liquid in stalls, lime should never be used. 

 It does not hold the ammonia, but rather causes its loss by 

 releasing it from any of its compounds. Ground limestone 

 is not so bad in this respect as burnt lime. Wood ashes 

 should never be used because the potassium carbonate will 

 drive off ammonia even more readily than burnt lime. 

 The use of lime in composting, however, is allowable, but 

 for a different purpose if proper precautions are taken 

 (Section 205, c). 



205. Methods of Use. — There are only a few points to be 

 brought out in a work of this kind. A more complete treat- 

 ment of the subject is better suited to a discussion of special 

 crops and methods of farming. 



(a) Fresh Manure. — Experiments show conclusively 

 that better yields are secured on ordinary soils from manure 

 hauled fresh to the fields than from manure that has stood 

 in the pile for some time even under optimum conditions. 

 This is principally due to the fact that all the fertilizing 

 material has been retained and that the maximum effect 

 of bacteria in decomposing organic matter and dissolving 

 mineral plant food has been obtained. Manure which has 

 been hauled fresh to the fields can be spread on the surface 

 of the soil and allowed to lie exposed without danger of loss 

 of nitrogen, for the sun will check bacterial action directly, 

 and also by drying the manure will thus deprive the bacteria 

 of their necessary moisture. Fresh manure can be applied 

 on top of the snow with success. No loss of ammonia will 

 occur, and as the snow melts the soluble fertilizing ingredients 

 soak into the soil. This practice, however, is not safe on 

 frozen hillsides where there is danger of loss of these soluble 

 compounds by being washed away over the frozen soil. 



(b) Well Decomposed Manure. — Sometimes, however, 

 it is not economical to spread manure at once. It may cost 



