THE SHRINKAGE OF MARKET HAY. yal 
LIMITATIONS OF RULES FOR MEASURING SHRINKAGE. 
If a definite rule for measuring shrinkage could be laid down, it 
could be used to advantage in all of the hay-growing sections. That 
there is a need for such a rule is shown by the number of inquiries 
received by the Department of Agriculture. Such a rule could be 
used to determine the yield of experimental plots, but its greatest use 
would be to the hay grower who hauls his hay on wagons to the barn 
and has easy access to wagon scales, for it would enable him to com- 
pute, to the ton, just how much hay he would have for sale after 
~deducting the amount needed on the farm. Again, if he grows hay 
for the winter feeding of stock, he could easily determine, by using a 
rule for shrinkage, how much live stock he could keep during the 
winter. Merely weighing the hay as it comes from the field, on its 
way to the barn, does not give a significant figure to the average hay 
grower, since he does not know whether the shrinkage will be 10, 20, 
or 30 per cent; indeed is not sure that there may not be a gain a few 
months later. 
The Rhode Island station used a rule allowing a 20 per cent re- 
duction in the weight of field cured hay to represent barn-cured hay. 
This rule was based on the usually accepted idea of practical farmers 
in that State. In 1902 the actual weights of field-cured and barn- 
cured hay were taken to check the accuracy of the 20 per cent rule. 
With one plot there was an error of about 6 per cent, in another about 
5 per cent, and in another about 0.5 per cent in total shrinkage. 
Tn each instance it was found that a 20 per cent allowance for shrink- 
age was too great.”’ 
The Kansas station says, in regard to the average amount of 
shrinkage: 
Men experienced in handling hay usually figure on about 20 per cent loss in the 
weight of the hay after itis put into the mow. The statement is also made that each 
bale (size and weight not given) will shrink from 2 to 5 per cent in weight. 
It appears that the amount of moisture retained in cured hay when stacked varies 
with different kinds of hay and with different conditions of curing. Ordinarily the 
loss in the weight of hay stacked when well cured and protected from loss other than 
that which may occur by natural shrinkage should not be greater than 10 to 15 per 
cent.”8 
According to this investigator, hay in the mow loses considerably 
more by shrinkage than hay in the stack, provided the stack is pro- 
tected from loss other than that which may occur by natural shrink- 
age; that is, loss from bleaching and rotting due to exposure to the 
weather. To prevent such loss it would be necessary to protect the 
top and sides of the stack, which is exactly what the barn does, and 
the amount of shrinkage would of necessity be the same in the barn 
27 Rhode Island Agricultural Experiment Station Bull. 82, 1902, p. 130-131. 
28 Kansas Agricultural Experiment Station Bull. 175, 1911, p. 331. 
