128 EXPERIMENT STATION RECORD. 



Influence of exposure upon the quantity and quality of yard 

 manure, W. Fkear {Pennsylrania Hta. Rpt. 1892^ pj). S5-93). 



Synopnin. — Tlio results of experiments on niauure stored in compact lieai)S in an 

 open dished yard covered with puddled claj-, and in a shed open on one side and 

 ■wholly aliovo ground, while not conclusive, indicate that the average loss for 

 the whole year (summer and wiuter) was less from the open j'ard than from the 

 shed. 

 To aid in determining the comparative economy of vStorino' niannre in 

 covered sheds open on one side and wholly above gronnd, and in open 

 dished yards covered with jjnddled clay, alternate loads of the manure 

 produced by " a herd of about 25 cows, a few steers and sheep used for 

 digestive experiments, a dozen calves and 10 horses," supplied with 

 the minimum amount of straw and sawdust consistent with cleanliness, 

 were carried to the two heaps. The heaps were compacted by allowing 

 the cattle to run on them an hour or two each day, and uniformity was 

 secured by allowing a few pigs to work them over. When the manure 

 was removed to the field, in August, two sets of samples were taken 

 from each heap, one chopped fine before being taken to the laboratory 

 and the other left unchopped. Manure ])roduced during the fall was 

 treated in the same manner, and when hauled to the field in February 

 was similarly samjiled. The samples were submitted to careful analyses. 

 While the results of carefully checked analyses show " that more pains 

 in sampling manure is needful if the results are to be worthy of dis- 

 cussion; that at least triplicate sampling is desirable, and that minute 

 differences are just as probably due to imperfections in sampling as to 

 real differences in the general substance under examination," they also 

 point out, with more or less defiuiteness, that — 



"(1) In both summer and winter the open-yard manure contained most moisture. 



'■'(2) In summer, the greatest loss of organi(! matter occurred in the exposed heap; 

 in the winter, though the duplicate analyses differ widely in result, the reverse 

 seems true. 



"(3) Judging by the residual amounts of potash, the o])en-yard manur*^ suffered 

 some loss hy leaching. 



"(l) The results, so far as nitrogen is concerned, agree with those for organic mat- 

 ter. Itis therefore evident that under these conditions of exposure, although we have 

 not the data from which to compute the absolute loss of valuable ingredients, the 

 manure lost relatively most from overheating — under the covered shed in the winter, 

 but when exposed to the sun in sununer. 



" (5) If the expressi(m of value adopted in the foregoing table is accepted,' the loss 

 from the covered shed in winter is shown to be greater than the gain from its use in 

 summer, without taking into consideration the factor of the cost of the shed^which 

 may, however, be partly covered by the gain in comfort of the animals protected 

 from excessive heat. 



" Since the results of analysis leave so much to bo desired in <()nnection with the 

 wiutertest, this will be repeated.'' 



Experiments made elsewhere are reviewed in whicli '^ the results in 

 favor of covering and compacting the manure while fresh are very pro- 

 nounced, so far as the percentage of loss is concerned. It is to be 



■Nitrogen 10 cts. per pound and })hosplioric acid and potash each 5 cts. 



