144 MASS. EXPERIMENT STATION BULLETIN 162. 



rowen crop in 1911 is doubtless explained by the fact that the original 

 clover plants (biennial or short-lived perennials) had then for the most 

 part died, that being the tliird yeav since seeding. 



The soil test work of the experiment station affords another oppor- 

 tunity of comparison of the effects of phosphoric acid and potash on 

 the hay crop (as in the other experiments with hay referred to made up 

 of timothy, redtop and clovers). Hay has occupied our south soil test 

 acre six years, but in only four of them was a second or rowen crop cut. 

 The soil is rather hght, the fertility only medium, even on the plots re- 

 ceiving a complete fertihzer, and in hot, dry summers the second growth 

 is hght. 



Average Increase in Six Hay and Four Rowen Crops (South Soil Test) 



(Pouyuls) . 



The striking superiority in effects produced by the potash is at once 

 apparent. 



Results obtained in soil tests In different parts of the State are similar 

 in kind, but the superiorit}'' of the j'ields on potash is much smaUer than 

 on our home grounds, ■ — a consequence, in my judgment, at least in 

 large measure, of the fact that the soils were undoubtedly in many cases 

 acid. These experiments were all tried before the fact that so many of 

 our soils are in need of lime was fully appreciated (1892 to 1895). 



Asparagus. — We have definite data on asparagus. In our substation 

 in Concord for asparagus investigation both phosphoric acid and potash 

 are applied ^ — in combination in each case with the other two plant-food 

 elements — under conditions which make it possible to determine the 

 specific effects. Each of the plots for which data are given has been 

 under uniform treatment for seven years. The phosphoric acid is ap- 

 plied in the form of acid phosphate, and the potash in the form of muriate. 

 The table presents the relative results of the apphcation of phosphoric 

 acid and potash for 1914 (the seventh year). 



