ANIMAL MANURES 95 



is nearly the same. The horse and the cow manure contain 

 more potash than the manure from hogs. On the other 

 hand sheep and hog manures run higher in phosphoric 

 acid. An explanation of this can probably be found hi 

 the fact that the horse c*nd the cow largely make use of 

 different sources of feed than those consumed by hogs and 

 sheep. 



Horse manure ferments very rapidly under certain 

 conditions, and the best method for the farmer to pursue 

 is to haul the manure to the field frequently and apply it 

 to a growing crop; but such method is often impracticable, 

 due to the extra labor entailed, inclemency of the weather, 

 and the fact that there is not always a growing crop avail- 

 abb. Where horse manure is kept in a pile for some time, 

 it must be packed down sufficiently to prevent violent 

 nitrification, followed by denitrification, which is known 

 as firefanging. This latter condition results in the loss of 

 much of the nitrogen, and the material is just as truly ashed 

 in the firefanged spots as though it had been in the fire. 

 When manures firefang, they heat and liberate gases both 

 injurious and uncomfortable to the animals. There is 

 little danger of firefanging of cow manure because this 

 manure will not heat. 



72. Effect of Exposure to the Weather. In handling 

 dairy cattle, it is absolutely necessary that the stalls be 

 kept scrupulously clean. In such a case it may be advis- 

 able that the manure be hauled out every day, if possible, 

 and spread upon the land that has, or is soon to have, a 

 growing crop. Preferably the manure should be plowed 

 in as soon as possible. It has been shown at the Maryland 

 Experiment Station that, when 80 tons of manure were 

 exposed to the weather for a period of one year, the weight 

 was reduced to 27 tons. At the Experiment Station of 

 the Dominion of Canada, when 2 tons of manure, con- 

 taining 1938 pounds of dry matter, were exposed for four 

 summer months, the dry matter was reduced to 655 pounds 



