2 BULLETIN 353, U. S. DEPAETMENT OF AGRICULTURE. 



but this variation is within rather narrow limits. The term "field 

 cured" is more indefinite, denoting that condition of forage which 

 obtains in general farm practice when the hay or fodder is consid- 

 ered sufficiently well cured or dried so that it will not spoil when 

 placed in bales, stacks, or in a haymow. In this stage the forage is 

 very seldom completely air dry. 



Most publications on forage crops use the term "field cured" to 

 denote the condition of the forage under consideration, but such a 

 term does not imply a uniform percentage of moisture, and little or 

 no care has ever been used to indicate even approximately the 

 moisture content of the forage when the yields were determined. It 

 is, therefore, impossible to interpret correctly many data found in 

 such publications. 



The variation in the moisture content of forage when yields are 

 taken is often greater than the actual difference in yield that we may 

 expect from improved varieties or improved methods. There is 

 little dependence therefore to be placed in experimental results along 

 these lines until this factor of error is eliminated, or at least greatly 

 reduced. The data presented in this bulletin are sufficient to sug- 

 gest a remedy for this difficulty, and it is hoped that experimenters 

 will consider carefully the method here indicated. 



Aside from the experimental value of this work, it has an economic 

 significance, in that it points out the relative weight value of forages 

 at different stages of maturity. However, the economic side of the 

 question is not discussed m detail and is given only as it forms a part 

 of the experimental data presented. 



GENERAL PLAN OF THE EXPERIMENTS. 



During 1914 a series of experiments was carried out to secure data 

 on which to base a sampfing system that would give greater accuracy 

 to field tests in forage experiments. In connection with the efficiency 

 of the sample method, investigations were also carried on to determine 

 the amount of moisture in forage plants at different stages of devel- 

 opment, the variation in moisture content due to locahty and to 

 cutting at different times of the day, and the differences in loss of 

 weight when samples are dried in the sun as compared with those 

 dried in the shade. Information was also secured on the rate of 

 moisture loss in forage in the early stages of curing and the changes 

 in moisture content of hay stored in bales and loose in a bam. 



In conducting the experiments at the various places the methods 

 followed were the same or varied only in minor details. HaH-bushel 

 and_ bushel cotton bags were used to receive all samples except the 

 largest, for which common burlap grain bags having a capacity of 2 

 bushels were used. For inclosing the bales of hay a close-weave 

 burlap was used. In taking samples of field-cured forage, care was 



