72 Effective Farming 



of the readily soluble plant-foods, will always occur in the case 

 of the urine and also in the case of the solid parts when the 

 manure is exposed to rain or snow. This loss can be lessened 

 by storing the manure in a concrete pit or a yard that has a 

 water-tight bottom or by spreading the manure on the field 

 where it is to be used soon after it is voided. By this latter 

 method the plant-food will leach out, but it will enter the soil 

 where it can be used by the plants. 



Fermentation, or the decomposing of the manure, takes place 

 rapidly. The manure as it leaves the animal is teeming with 

 bacteria from the digestive system and these cause it to decom- 

 pose rapidly. Two classes of bacteria are at work one known 

 as aerobic, which require oxygen for their development and 

 the other known as anaerobic, which work where air is either 

 lacking or present only in small quantities. When manure 

 is fresh it is likely to be rather loose and, if it dries, it soon be- 

 comes aerated. Under such a condition the aerobic bacteria 

 start to work, changes are rapid, and much heat occurs. This 

 fermentation is undesirable, as it destroys the organic matter 

 and liberates the nitrogen. The action of these bacteria can 

 be lessened by compacting the manure and by wetting the pile 

 to exclude the air. The losses from aerobic fermentation are 

 greater in horse, sheep, and poultry manures the hot ma- 

 nures than they are in cattle and swine manures. 



Anaerobic bacteria work where most of the air is excluded 

 from the pile. The changes caused in the manure are unfa- 

 vorable to the loss of nitrogen and the manure rots without 

 much loss of plant-food. This kind of rotted manure is very 

 valuable, as it contains readily available plant-food. When 

 a vegetable-grower places manure and soil in layers in a pile 

 and packs and wets the pile, he makes conditions favorable 

 for anaerobic bacteria to work. This way of handling manure 

 is known as composting it and the pile, as a compost pile. 

 The manure rots, but still contains much readily available 

 plant-food. 



