1902.] PUBLIC DOCUMENT — Xo. 33. 17 



Per Cent. 



Manure, 100.0 



Nitrate of soda, 98.1 



Dried blood, 94.5 



Sulfate of ammonia, 89 . 7 



No nitrogen, 84.3 



In yield of straw the rank is : — 



Per Cent. 



' Barnyard manure, 100.0 



Nitrate of soda, 98.1 



Sulfate of ammonia, 97.5 



Dried blood, 96.3 



No nitrogen, 88.4 



It will be seen tliat the different materials stand more 

 nearly together this year than is the average of preceding 

 years. The manure stands relatively higher than in former 

 years, but the fertilizers stand in the same relative order, 

 nitrate of soda proving the most efficient of the nitrogen 

 fertilizers, and sulfate of ammonia the least as measured by 

 grain production, while it is slightly ahead of the blood in 

 the yield of straw. The comparatively even results of this 

 year are doubtless to be accounted for chiefly by the fact 

 that the crop of this season, the soy bean, is one capable 

 of drawing upon the atmosphere for a considerable share 

 of tlie nitrogen it requires. The development of nodules 

 upon the roots of the crop this year was very abundant. In 

 spite of this fact, it will be noticed that the crop on the 

 no-nitrogen plots stands considerably below that on the 

 other plots. It is, however, doubtless much more nearly 

 on an equality with them than would have been the case 

 with a crop not belonging to the clover family. 



II. — The Relative Value of Muriate and High-grade 

 Sulfate of Potash. (Field B.) 

 This experiment has been in progress since 1892. The 

 object is to determine the relative value for different crops 

 of the two leading potash salts, muriate and sulfate, when 

 used in equal quantities continuously upon the same land. 

 The field contains eleven plots, of one-eiglith of an acre 

 each. Six of these have been yearly manured with muriate 



