THE SHRINKAGE OF MARKET HAY. he 
one case (experiment 5, p. 5) clover hay, which lost only 22.6 per 
cent by shrinkage, was partly musty at the end of the experiment. 
Considering that the normal water content of cured hay amounts 
to 13 per cent, the percentage of water in this particular lot at the 
time it was put in the barn was 32.66 per cent. | 
The Kansas station *% has found that alfalfa containing as much 
as 24 per cent of water will cure out properly in the stack. In the 
semiarid West it may be safe to stack hay containing more than 24 
per cent of water, while in the South and parts of the East, where 
the humidity is greater and unfavorable weather often prevails, it 
may not be safe to put up hay with such a large water content. 
THIRD FACTOR—NORMAL WATER CONTENT WHEN CURED. 
The normal water content of cured hay is the third important fac- 
tor to be taken into account. Shrinkage in hay practically ceases 
when the water content reaches a certain point which varies with 
climate (See “Average,” Table IT), and not until then is the curing 
process finished in barn or stack hay, which may then be rightly 
classed as well-cured, marketable hay. As the water content of hay 
baled from the windrow or cock is sometimes above normal, it is 
subject to shrinkage in the bale. The average normal water content 
of hay is the amount of water usually contained in hay after it has 
passed through the ‘‘sweat” or “‘heat’’ in the stack or barn and is 
ascertained by averaging all available water-content analyses. In 
the case of timothy (see Table IT), 221 water analyses have been 
averaged, giving an average of 11.6 per cent. In the cases of other 
hays fewer analyses are available, which probably accounts, in part 
at least, for the variation in the figures presented as representing 
the average water content of the different grass and lecume hays. 
FOURTH FACTOR—MINIMUM WATER CONTENT. 
Sometimes hay becomes very dry. In fact, in the West “dry” 
hay is discriminated against on account of the loss by shattering and 
because it is thought to lack. palatability. The water content in 
“dry”? hay is shown in Table II, under “minimum.” When 
the percentage of water in hay is so low that the air will no 
longer absorb any of it, the hay is said to contain a minimum amount 
of water. The minimum water content which is the fourth factor 
depends upon the humidity of the air, length of time the hay is 
exposed to such air, and the amount or bulk of hay in the stack or 
barn. 
To lower the natural minimum it is necessary to subject the hay to 
artificial drying, as is done in the laboratory when making a deter- 
mination of dry matter. The figures given in the table do not imply 
13 Kansas Agricultural Experiment Station, Bull. 155,1908. pp. 258-259. 
