422 MISCELLANEOUS FARM SUBJECTS 



mentation is necessary to the successful rotting of manure. If the 

 heap is too loosely built the decomposition is too rapid ; the materials 

 useful for the formation of humus in the soil are destroyed, and the 

 nitrogen, especially that of the urine, escapes into the air, partly 

 as ammonia, partly as free nitrogen. On the other hand, if the 

 manure is too firmly packed the decomposition may be too slow and 

 the manure will not become sufficiently disintegrated to produce 

 the best effect in the soil. 



It has i>een found that barnyard manure contains in large 

 numbers microscopic organisms which cause denitrification that 

 is, they decompose nitrates and set the nitrogen free in the gaseous 

 form. For this reason nitrates are not found in fermenting manure 

 and should not be mixed with it. It has even been asserted that the 

 application of manure may result in considerable losses of nitrogen 

 from the nitrates of the soil from this cause, but recent experiments 

 make it clear that such losses occur, if at all, only in case of exces- 

 sive applications of manure, and that on the other hand ordinary 

 applications of manure favor nitrification, or the formation of ni- 

 trates, in the soil. 



A powerful means of controlling fermentation is the supply of 

 moisture. The addition of water lowers the temperature and thus 

 retards fermentation. By filling up the pores of the mass and ex- 

 cluding the air it checks aerobic fermentation when this becomes 

 too active. French authorities maintain that the principal precau- 

 tions necessary to prevent losses of ammonia consist simply in reg- 

 ularly and properly watering the manure with the leachings. In 

 case of drought, if the leachings are insufficient, the lack should be 

 made up with water. 



The need of keeping manure moist is especially marked in 

 case of horse manure, which is naturally dry and decomposes with 

 great rapidity. The same is true in a less degree of sheep manure. 

 The common and harmful fire-fanging is the result of an insuffi- 

 cient supply of water and may be readily checked by sprinkling. 

 The sprinkling, however, should be regularly done and the heap 

 kept in a constant state of moisture, otherwise the alternate wetting 

 and drying will result in a loss of ammonia. Preservation of man- 

 ure in this manner is generally practiced in Europe, and the product 

 obtained is highly esteemed as a fertilizer. It is very dark colored, 

 or even black, and acquires a highly offensive odor, while the straw 

 in it loses its consistency and becomes soft and incoherent. This 

 black substance is held by certain French agriculturists to possess 

 special value as plant food. A method employed in the preparation 

 of this well-rotted manure in France is as follows: The manure is 

 placed on slightly inclined plats of packed earth or cement, so ar- 

 ranged that the leachings drain out into a pit, from which they are 

 pumped up and distributed over the manure heap. It is usual to 

 provide two manure plats, so arranged that when one is full (when 

 the manure is 8 to 10 feet high) it may be allowed to ferment un- 

 disturbed while the other is used. 



