1903.] PUBLIC DOCUMENT — No. 33. 113 



but it may be that the relative standing of the no-nitrogen 

 plots is higher than it would have been had the crop of 

 potatoes grown to normal maturity. It will be remembered 

 that blight and rot prevailed to a considerable extent, and 

 these would naturally injure the potatoes with the ranker 

 growth more than those where the growth was less luxuriant. 

 It does not seem, therefore, that we are justified in conclud- 

 ing that the after-effect of the so}^ beans is as useful as the 

 relation between the figures appears to indicate. 



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

 Sulfate of Potash. (Field B.) 



The object of this experiment, which has been in progress 

 since 1892, is to determine the relative value for different 

 crops of the two leading and cheapest sources of potash, 

 viz., muriate and high-grade sulfate. These salts are used 

 in equal quantities continuously upon the same "land. The 

 field contains eleven plots, of approximately one-eighth of 

 an acre each. Of these, six have been yearly manured with 

 muriate of potash and five with the high-grade sulfate. 

 ■From 1892 to 1899 inclusive these salts were used at the 

 rate of 400 pounds per acre ; since 1900 the rate of appli- 

 cation has been 250 pounds per acre. Fine-gi-ound bone at 

 the rate of 600 pounds per acre has been yearly applied to 

 all plots. Various crops have been grown in rotation, 

 including potatoes, field corn, sweet corn, grasses, oats and 

 vetch, barley and vetch, winter rye, clovers of various kinds, 

 sugar beets, soy beans, and cabbages. Most of these crops 

 have been grown during several different years. All have 

 with few exceptions given uniformly large yields. The 

 results to date may be summarized as follows : among the 

 crops grown, the potatoes, clovers, cabbages, and soy beans 

 have usually done much the best on the sulfate of potash ; 

 the yield of corn, grasses, oats, barley, vetches and sugar 

 beets has been about equally good on the two salts ; the 

 quality of the potatoes and sugar beets produced on the 

 sulfate of potash plots has been distinctly better than that 

 of the crops produced on the muriate of potash. 



The crops of the past year have been mixed timothy and 

 clover, cabbages, potatoes, and onions. 



