When data on these vital facie are included slot ae 7 os 
results of a shrinkage experiment, the loss or gain in weight, whether 
it be large or small, at once becomes easy to interpret and will be 
found to be in accord with the natural laws that govern the curing 
of hay. 
Many shrinkage experiments have been made without determining 
the water content, either at the time the hay was taken from the field 
or at the end of the experiment. (See experiments 2, 4, 5, and 6.) 
The hay was merely weighed when put into the barn or stack and 
again at a specified later time and the amount of loss by shrinkage 
was determined by the difference between the two weights. It is 
the publishing of the results of such experiments, especially when a 
comparatively large loss occurred, that has led many hay growers to 
believe that an actual instead of an apparent loss takes place when 
hay is in storage for some time. 
This belief has been further strengthened, in some instances, by 
statements to the effect that besides the loss of water there has been 
a loss of dry matter, because of fermentation (the amount of which, 
however, is unknown) without giving adequate evidence to show that 
‘any such loss has occurred or even that conditions were favorable 
for fermentation.!! The loss of dry matter will be discussed later. 
FACTORS AFFECTING DETERMINATION OF SHRINKAGE. 
FIRST FACTOR—WATER CONTENT WHEN CUT. 
There is a great difference in the amount of water contained in 
grasses and legumes when cut, while curing or being made into hay, 
and after becoming well-cured hay. A knowledge of the normal 
water content of hay in these various stages will throw light on what 
may be expected to happen during the final stages of curing. Table I, 
compiled from Henry’s Feeds and Feeding, shows the average water 
content of different kinds of hay, as determined by a ie series of 
tests. 
TABLE 1.—Water content of ‘‘unwilted’’ hay. 
ae : Difference 
Average. | Minimum. |Maximum.| between 
\ extremes. 
a 
Per cent. Per cent. Per cent. Per cent. 
phereLuy ab dierent Stages. s.s<.\cecss cuss eecises = 61.6 47.0 78.7 31-7 
Eee RnOp A A OIOOM 8. Sync Le See ag aa oe 65.3 51.5 76. 2 24.7 
HaeCmelovier, aicciflelemt SLALES =. css ee see ee eee 70. 8 47.1 91.8 BieG 
‘Alsike clove Crain: bloom 2232 aa ee ee oe ee 74.8 Ce tid 
Alfalfa, at different StAZCS SSS aeceoe ae aeons eee eee 71.8 49.3 82.0 32.7 
Cowpeas EE Pad ep, <a hn ais pay ee eae ee 83.6 72.8 93.1 20.3 
OSD CPS Bs ret Sonia ecu ate = cee op ena mae st) By ain ee 75.1 63.6 81.5 17.9 
AHOETS OMBOT AS Gene Sens ee arse ates ge ee a oe ae a 61.0 51.1 70.8 19.7 
GALEN aS a ate See ee aes ee a aie eaten e oe. Meal Oe, Se (628 acs Sows SSE SSe Se ee 
CO BP Se Tes aa DS Pe gS ree Teena SAE heehee AY) 102 Qe cock Pat OSE eee eee 
BEE Vice pre eee tee Se NS A ne pees Beem 180 0- |S. Soe Se ee eee 
AV RURY RDS 2 Sele Ts ae ed ea RE eens et PU 42,67 |S cnet sa A ee 
11 Utah Agricultural Experiment Station, Third Annual Report, 1892, p. 47-48. U.S. Department of 
Agriculture, Bulletin 353, 1916, p. 6, 17. 
