36 EXPERIMENT STATION. [Jan. 



on these plots must be due to residual nitrogen, which diu-ing 

 the progress of the experiment has gradually accumulated. 

 Calculation, however, shows that the crops harvested from 

 these plots during the years that the experiment has continued 

 must have removed from the soil larger quantities of nitrogen 

 than had been applied. 



The fact that the soil has been so heavily limed twice within 

 recent years seems to preclude the conclusion that the relative 

 failure of the clover is due to an acid condition of the soil ; 

 and, indeed, careful chemical analyses of samples taken last 

 spring show that the soil of these plots does not, as a rule, 

 contain appreciable quantities of free acid. We are unable, 

 then, at present to account for the results obtained ; but careful 

 chemical and biological investigations will be carried out, with 

 a view to throwing light upon this most important question. 



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

 Sulfate of Potash. (Field B.) 



In this experiment, which was begun in 1892, muriate of 

 potash is compared with high-grade sulfate, on a basis of such 

 applications as will furnish equal actual potash per acre in con- 

 nection with an annual application of fine-ground bone at the 

 rate of 600 pounds per acre. Potash has been applied in differ- 

 ent years in varying quantities. At first the applications were 

 exceptionally heavy, — 350 to 400 pounds per acre of these 

 salts were applied. Since 1900 each has been applied at the 

 rate of 250 pounds per acre annually. 



The crops during the progress of the experiment have em- 

 braced nearly all those common to this latitude. During the 

 past year they have been : cabbages on two plots ; asparagus, 

 rhubarb, raspberries and blackberries, all on each of two plots ; 

 corn on four; and squashes on two. The rates of yield of the 

 various crops on the different fertilizers are presented in the 

 following table : — 



