MANURES AND FERTILIZERS. 117 



which is the largest quantity that the figures show is 

 necessary. The trouble is, that the fertilizing elements 

 of manure are not rapidly set free ; their action is 

 proverbially slow, and from this slow action comes the 

 great "lasting power" of manure. It is lasting because 

 it cannot be quickly used. The availability of the ma- 

 nure is increased, but at the loss of considerable of the 

 nitrogen, by rotting, especially when assisted by work- 

 ing over the pile, breaking up the lumps, and allowing 

 the air free access to all parts of the heap. 



But eight and one-half cords of manure, however 

 short and well rotted it may be, will not satisfy the re- 



FIG. 14. WOODEN FRAME FOR PLANT BED (German). 



quirements of the crop. It is likely that not more than 

 thirty per cent of its fertilizing elements can be used by 

 tobacco the first year, although this percentage is gov- 

 erned considerably by the length of time the manure re- 

 mains in the soil before the plants are set, and upon 

 temperature and moisture. Yet the longer it thus re- 

 mains in the soil, the more likely is the loss of nitrogen 

 from evaporation and leaching. This loss is again offset 

 by the uniform distribution of what nitrogen is not thus 

 lost, and the more available form in which it exists. 



It is, therefore, very difficult to tell how much 

 manure to use, if that, alone, is to be depended upon, 



