No. 7. DEPARTMENT OF AGRICULTURE. 455 



knowledge concerning the possibilities of loss of the constituents 

 from manures. 



In experiments that were begun at the New Jersey Station, in 

 1898, it was possible to study two phases of this question, first, as 

 to the losses that are liable to occur by exposing manures to the 

 action of the rains, making the conditions similar to those which 

 would occur were the manures left in the open yard. Data have 

 been tabulated from year to year, and up to the present time, five 

 years' records are available for study. It was shown by careful 

 chemical control, that in the solid portion of the manure, only the 

 loss of organic matter was 37.6 per cent., while in the solid and 

 liquid combined, it was 40.7 per cent. The loss of nitrogen in the 

 solid was 38.4 per cent., and in the solid and liquid manure 52.6 per 

 cent.; the loss of phosphoric acid in the solid manure was 46.8 per 

 cent., and of the solid and liquid portion, 48 per cent.; the loss of 

 potash in the solid manure was 44.4 per cent., and of the solid and 

 liquid manure 57.6 per cent. Or, m other words, of the total pro- 

 duct, for every 100 pounds each of nitrogen, phosphoric acid and 

 potash in the original manure, 52.6 pounds of nitrogen, 48 pounds 

 of phosphoric acid and 57.6 pounds of potash were lost by leach- 

 ing during an average of about 100 days. There may, of course, have 

 been a slight loss from fermentation; but inasmuch as the manures 

 were exposed from about the first of February to the middle of May, 

 the loss from this source could not have been serious, as the tem- 

 perature was too low to permit such activities. It may be said, on 

 the other hand, that the losses from the solid manure were very 

 much less than from the solid and liquid manure, and that, there- 

 fore, comparisons on that basis would be more in accordance with 

 the actual losses that occur. This argument has been used, and yet 

 when it is remembered that more than one-half of the nitrogen and 

 potash of the total manure product is contained in the liquid por- 

 tion^ if this portion were not considered at all, then the losses would 

 be multiplied by just that amount. However, in order that we may 

 have some definite and practical idea of what these individual losses 

 mean, if they are applied in the aggregate, I have calculated the 

 amounts possible to lose in this way for the cows in Pennsylvania, 

 and find that if these maximum losses were incurred, the nitrogen 

 would be equivalent to 209,455 tons of nitrate of soda, 139,200 tons 

 of acid phosphate and 54,086 tons of muriate of potash. These 

 would cost, if purchased in this form, $14,157,710. 



It is not to be understood by this that I say that these constitu- 

 ents are lost in this proportion, or that they would be worth as much 

 as the constituents that are in the commercial fertilizers. Never- 

 theless, I do believe, and experimental data bear me out, that the 

 constituents in manures, particularly nitrogen, may be, on the aver- 

 age, quite as useful and return the farm quite as large an increase 

 per unit, particularly the nitrogen, as those bought in commercial 

 fertilizers. If the farmers do not believe this, and they are allow- 

 ing the constituent elements of their manures to be lost, the best 

 way to prove the fact to their own satisfaction, is to stop the losses 

 upon their farms. 



The practical question that may be asked in reference to this 

 matter is, how is the farmer to save these constituents? Experi- 



