DAIRY AND SEED IMPROVEMENT MEETINGS. 397 



potash, this comparison is not adequate for determining the 

 relative value, since manures serve certain purposes fertihzers 

 cannot serve. Farm manure is of a very complex composition. 

 It contains more or less of all of the elements contained in the 

 foods given to the animals and in the litter. It is rich in organic 

 matters, being composed chiefly of vegetable substances. Or- 

 ganic matter is the source of humus to the soil and is of much 

 value. Soils need humus and it can only be supplied by the 

 addition of organic matter in farm manure or by plowing under 

 green crops. Commercial fertilizers do not supply humus. 



The urine is by far the most valuable part of the excreta of 

 animals. It is not sufficient to save the solid droppings but the 

 liquid should be collected as well. The amount of fertilizing 

 constituents in a manure stands in direct relation to those in the 

 food. The nitrogen in a food exerts a greater influence on the 

 quality of the manure than any other constituent. It is the 

 most costly fertilizing constituent. It undergoes more change in 

 the animal's stomach than the mineral constituents and rapidly 

 escapes from the manure in fermentation. Even if all the 

 manure is saved and proper absorbents are used, barnyard 

 manure is still an unstable product. It rapidly undergoes 

 changes. The deteriorations of manure result from fermenta- 

 tion and from weathering or leaching. Farm manure loss from 

 destructive fermentation may be largely prevented by the use 

 of proper absorbents and by keeping the manure moist and com- 

 pact. The loss from leaching may be prevented by storage under 

 cover or in water tight bins. 



If practicable, manure should be removed and spread on the 

 field at short intervals and in that case the loss of valuable 

 constituents is not very great. When the manure must be 

 stored for some time the difficulties of preservation are greatly 

 increased. These matters are fully discussed in the Farmers' 

 Bulletin above referred to. Every farmer is urged to get a 

 copy of the United States Department of Agriculture Farmers' 

 Bulletin 192, study it, and put its general principles into prac- 

 tice. If the present shortage of potash should lead the Maine 

 farmer to conserve millions of dollars' worth of plant food 

 which are now being neglected through lack of care in the 

 collection and handling of farm manures it would largely help 

 to offset the losses that may come in 191 5 from a potash short- 

 age. 



