4 BULLETIN 873, TJ. S. DEPARTMENT OF AGRICULTURE. 



fifth of the tonnage harvested. If it were true that an actual loss 

 of nutrients takes place, there would be good reason for the hay 

 grower to become alarmed and seek information that will enable him 

 to prevent it. That the department is often asked to furnish data 

 regarding methods of curing and storing hay which will tend to pre- 

 vent shrinkage is evidence that many farmers believe that the 

 question of shrinkage is a serious one. 



Some farmers make a practice of weighing newly made hay just 

 before it is put into the barn and wish to know the amount of shrink- 

 age that will take place, under average conditions, in order to be able 

 to estimate the amount of hay there will be after the shrinkage has 

 ceased. This knowledge is desirable when estimating the quantity 

 of hay that is needed on the farm or the quantity that can be sold at 

 some later date. Buyers and shippers of hay often buy hay baled 

 from the cock or windrow and then hold it for some time before 

 selling it. A general knowledge of the question of shrinkage would 

 be of value to them. 



It is the purpose of this bulletin (1) to give data on the average 

 water content of several kinds of hay at harvest time, (2) on the loss 

 of water and dry matter during the curing process, (3) on the loss 

 during the time the hay is stored, and (4) to point out when shrinkage 

 in hay is an actual loss and whom this loss affects, and when the 

 apparent loss, is not a real loss, but is simply a natural result of the 

 normal curing process that all good hay must undergo. 



RESUME OF DATA ON SHRINKAGE. 



During the past 30 years many experiment stations have con- 

 ducted experiments to ascertain the loss occurring in hay when 

 stored for varying lengths of time in the barn or stack. The follow- 

 ing selected data, arranged in order of decreasing percentages of 

 loss reported, show what has been accomplished in trying to ascer- 

 tain the rate of shrinkage in hay: 



(1) The largest loss due to shrinkage is reported by the Pennsyl- 

 vania station. 1 Two plots of clover, not adjoining, were cut at 

 each of three periods of growth, (1) the clover heads in bloom, (2) 

 partly dead, and (3) nearly all dead; the dates of cutting were June 

 22, July 3, and July 19. The hay was weighed when put into 

 the barn, and then reweighed five or six months later, in order to 

 determine the weight of the "dry" hay. The hay cut in bloom 

 lost 42.2 per cent, that cut when partly dead lost 44.2 per cent, 

 and that cut when heads were all dead lost 25.7 per cent. 



(2) At the Missouri station 2 a stack of second-growth clover, 

 weighing when put up in July 6,514 pounds, shrank in weight by 

 the following March to 4,548 pounds, a loss of 30 per cent. 



1 Pennsylvania State < ollege, Kcportfor 1886, pp. 271-276. 



2 For report of experiment see Michigan, State Board |of Agriculture and Experiment Station, 1901, 

 p. 287. 



