282 FEEDS AND FEEDING 



value in periods of 2 to 5 months. Obviously, the loss falls on the 

 constituents which are most soluble and most quickly available to plants. 



Farm manure is teeming with bacteria, molds, and yeasts, the numbers 

 often running into billions for each gram of manure. These organisms in 

 general break down the complex compounds of the manure into simpler 

 ones, which are soluble. Some, of these changes are advantageous, as they 

 make the plant food more available to crops, but under improper condi- 

 tions of storage much of the nitrogen in the manure may be lost thru 

 these fermentations. When the manure is dry or loosely packed, the bac- 

 teria which thrive in the presence of air develop profusely, causing 1 1 hot ' ' 

 fermentation. In this process there is a rapid formation of ammonia, 

 much of which passes as gas into the air. The strong smell which every 

 farmer has noticed in close horse stables is due to this escaping ammonia 

 gas produced by the breaking down of nitrogen compounds in the urine. 

 In still other changes which may take place free nitrogen gas may be 

 formed, which is likewise lost into the air. When the pile of manure is 

 well packed and is kept damp, these changes can not go on, but only the 

 beneficial decompositions which render the plant food more available and 

 produce what is termed " well-rotted manure. " If the manure is very 

 loose and dry, "fire fanging," may occur, when the manure becomes 

 grayish or dusty in appearance. This change, produced by certain fungi, 

 seriously injures the manure. Phosphoric acid and potash are not lost 

 thru fermentation, but heavy losses may occur thru leaching. 



443. Care of manure. To prevent loss in manure, the urine should 

 be saved by having tight gutters and using plenty of bedding. If possible, 

 the manure should be drawn directly to the fields and spread each day. 

 This is not advisable, however, in winter on very sloping land when 

 covered by deep snow, as much fertility may wash down the hill in the 

 spring. When manure can not be spread on the land, it should be stored, 

 preferably in well-packed piles kept moist to prevent hot fermentation, 

 and preferably under cover or in a manure pit. If hogs or cattle have 

 access to the shed, they aid in firming the pile. It is an excellent plan 

 to mix the manure from horses or sheep, which is drier and therefore called 

 "hot manure," with that from cattle or pigs, which contains more water. 

 In Europe manure is often stored in pits and cisterns. When it is neces- 

 sary to leave manure out of doors, the pile should be made high and com- 

 pact, so that rains will not soak thru, and should be built with the sides 

 perpendicular and the top sloping toward the center so that all rain will 

 soak into the pile instead of draining off as from a stack of hay. It is im- 

 possible to prevent all waste in caring for manure, but under proper 

 management not over 10 to 20 per ct. of the nitrogen and practically none 

 of the phosphoric acid and potash will be lost. 



