148 MASS. EXPERIMENT STATION BULLETIN 212. 



Table 9. — Yields per Acre, Limed Portion of Field. 



1 By difference. 



The large and consistent differences secured through the use of potash 

 indicate that whatever effect the lime may have had on the availability 

 of soil potash was relatively insignificant. This checks the results secured 

 on the South Soil Test, as already discussed. 



Miscellaneous Effects of Fertilizers on Crops. 



Even though the fertilizer appUcations were in some cases doubled, 

 as indicated on page 142, either the soil conditions were unfavorable or the 

 amount of plant food applied was too small to give satisfactory crops of 

 onions or potatoes. The yield of 488 bushels of onions on the limed com- 

 plete fertiHzer plot in 1900 is indeed well above the average, but still is 

 not a large yield. In 1898 and likewise in 1901, the crop was a failure. 

 The yield records do, however, indicate two things very strongly: first, 

 the great importance to the onion crop of maintaining a suitable reaction 

 of the soil; and second, the need bj^ the crop of large quantities of all 

 three of the essential plant foods. The potato crops of 1897 and 1902 

 were virtual failures. 



The cabbage crop of 1917 was remarkably satisfactory and furnishes 

 several illustrations of the fact that crops of the same size may be secured 

 through radically different plant food treatments. As an illustration, the 

 crop on the limed half of Plot 9, which in 1917 had been receiving phos- 

 phoric acid and potash annually for twenty-seven years, was the same 

 as the crop on complete fertilizer without lime. Neither one of these, how- 

 ever, approached the crop produced \dth complete fertilizer and lime. 

 Again, the crop on the limed portion of Plot 6, which had received no 

 potash for twenty-seven years, was almost identical with that on the 

 limed portion of Plot 7, which had received no phosphoric acid for the 



