Sail Fertility 69 



process that causes the manure to turn white whenever a pile 

 is left exposed for a time. Firefanging is caused by fungi 

 and the manure so affected is of little value. The liquid por- 

 tion of horse manure is rich in nitrogenous compounds, but 

 soon after it is voided bacteria start to work on these com- 

 pounds and set ammonia, a gas, free. As ammonia contains 

 nitrogen, the fermentation means a loss of this product. Much 

 of the fertility of horse manure can be saved by mixing the 

 manure with that of cattle in the storage place. On account 

 of its dry condition horse manure is known as a hot manure. 



Cow manure is about equal in fertilizing value to horse ma- 

 nure, but it contains less fiber, consequently, less humus-form- 

 ing material. Owing to its large percentage of moisture, it is 

 known as a cold manure. A ton of cow manure contains on 

 the average about half as much dry matter as a ton of horse 

 manure. It does not firefang and it decomposes slowly. 

 When stored it should be protected from the weather to pre- 

 vent loss of plant-food. 



Hog manure, like that of cattle, is a cold manure and de- 

 composes slowly. The comparative quantity of plant-food 

 it contains can be .learned from Table I. 



Sheep manure is rich in nitrogen and potassium, is dry, and 

 decomposes rapidly. It is very concentrated and is often 

 sold in bags like commercial fertilizer. 



Poultry manure is very concentrated and is rich in nitrogen. 

 On account of being so concentrated it should be mixed with 

 litter or with other kinds of manure when applied to the soil. 

 It is very valuable for such crops as onions that require a large 

 quantity of nitrogen. 



31. Composition and character of farm manure. Farm 

 manure is variable in composition and character, due chiefly 

 to the kind and quantity of litter used, the class of animals by 

 which the manure is produced, the age and the kind of work 

 done by the animal, the feed of the animal, and the way in 

 which the manure is handled. 



