MOISTU-RE CONTENT AND SHRINKAGE OF FORAGE. 



17 



made with, only one sample. Table II also shows that the samples 

 of field-cured material are less consistent than samples of green 

 material when compared with bulk lots of the same forage dried 

 under similar conditions. 



RELATIVE VALUE OF SAMPLES OF DIFFERENT SIZES. 



The figures on the relative value of samples of different sizes as given 

 in Table III are not conclusive. There is a general, though not 

 consistent, decrease in the probable error as the size of the sample 

 is increased, but what would otherwise have been an expressive array 

 of averages has been spoiled by the excessive probable error in the 

 8-pound field-cured sample of alfalfa at Chico, Cal. The average 

 probable error for the 8-pound samples, including the Chico results, is 

 0.515 per cent; if we eUminate the Chico results it would be 0.281 per 

 cent, which perhaps is nearer what might ordinarily be expected. It 

 will be noted that as the green samples of alfalfa and of tall oat-grass 

 increase in size, the greater was the percentage of loss in curing, as 

 indicated by the column headed "Moisture in original samples" in 

 Table III. This fact makes it seem probable that there was a loss, 

 by fermentation, of matter other than water, but such a loss would 

 not mean an increase of error in the use of samples when the samples 

 are of a uniform size. 



On account of the difficulty of curing samples of green forage they 

 must necessarily be comparatively small, and when used in correcting 

 actual field weights the samples, whether green or field cured, must be 

 small enough to admit of easy handling. From the data presented 

 in the table, it seems that the 4-pound field-cured and the 8-pound 

 green samples are nearly as accurate as the larger ones. Considering 

 accuracy, the facility of handling, the ease of figuring percentages, 

 etc., 5-pound samples of field-cured and 10-pound samples of green 

 material are recommended as the most desirable for practical work. 



EFFECT OF REPLICATING THE SAMPLES. 



The data on the effect of replicating the samples are found in Table 

 IV, where the probable error has been expressed for single samples, 

 replicates of three, and repUcates of five and six. 



Table IV. — Average of the probable errors of one, three, and five or six samples. 



Number of replica- 

 tions. 



Field-cured material. 



Green material. 



Grand 



2- 



pound. 



4- 



pound. 



6- 

 pound. 



8- 

 pound. 



Aver- 

 age. 



4- 

 pound. 



8- 

 pound. 



12- 

 pound. 



16- 

 pound. 



Aver- 

 age. 



aver- 

 age.. 



One 



Per ct. 



1.006 

 .458 

 .445 



Per ct. 



1.243 

 .668 

 .548 



Per ct. 



0. 818 



.397 



353 



Per ct. 



0.994 

 .473 

 .515 



Per ct. 



1.015 

 .499 

 .465 



Per ct. 



0. 686 



.331 



.278 



Per cf. 



0.5S6 

 .277 

 .257 



Per ct. 



0.407 

 .156 

 .187 



Per ct. 



0.486 

 .256 

 .212 



Per ct. 



0.527 

 .255 

 .234 



Per ct.. 

 0. 777 



Three 



.377 





.349; 







21216°— Bull. 353—16- 



