30 HATCH EXPERIMENT STATION. [Jan. 



phosphate gives a very inferior crop, — the poorest, indeed, 

 in merchantable onions of any phosphate used. This result 

 is strikingly confirmatory of the results obtained in the field 

 where phosphates are under comparison on the basis of 

 equal money's worth. 



VI. — Comparison of Different Potash Salts for Field 



Crops. (Field G.) 



Since 1898 the following potash salts have been under 

 comparison for various field crops : kainite, high-grade sul- 

 fate, low-grade sulfate, muriate, nitrate, carbonate and sili- 

 cate. Each is applied annually to the same plot, and all 

 are used in such quantities as to furnish equal potash to 

 each plot. All plots are equally manured with materials 

 furnishing nitrogen and phosphoric acid. There are forty 

 plots, in five series of eight plots each, each series including 

 a no-potash plot and one for each potash salt used. The 

 area per plot is about one-fortieth of an acre. The crops 

 the present year have been wheat on one series of eight 

 plots, and corn of four different varieties on the other four 

 series. 



A. — Wheat. 



The variety of wheat was the Turkish Red Winter, seed 

 of which was received from the United States Department 

 of Agriculture. The soil is rather heavy, and the seed was 

 received so late that it was got in somewhat later than de- 

 sirable, viz., October 13. It was sown broadcast at the 

 rate of five pecks to the acre, and covered with the Acme 

 harrow. Owing no doubt chiefly to the lateness of sowing, 

 there was some winter-killino;. This was most severe on 

 the no-potash, kainite and the two sulfate plots. The 

 whole field was harrowed about the middle of May. The 

 growth was unusually healthy for this section, although all 

 plots were slightly affected by rust. The grain was plump, 

 hard and of good quality. The yields were as follows : — 



