A STUDY OF FACTORS INFLUENCING THE YIELD OF POTATOES 1241 



Altho six growers are too few to permit of the drawing of definite conclusions 

 as to the shallowest planting found, there is considerable evidence that 

 planting not more than 2 inches deep in the heavy soils of Steuben County 

 is desirable, at least in a year as wet as was 1912. Under a constant rate 

 of planting at all depths, and with the least manure and fertilizer used at 

 the shallowest depth of planting, this depth gave the highest average 

 yield and the smallest percentage of field-rotted tubers in 1912. In fact, 

 the percentage of field rot increased with the depth of planting. Assuming 

 that there had been no rot from blight and wet weather that year, the 

 average yield of the fields planted at the shallowest depth would still have 

 been the highest. 



The relation of depth of planting to yield in Monroe County in 1913 is 

 shown in table 72. It is clear from this table that 'in 1913, planting shal- 



TABLE 72. RELATION OF DEPTH OF PLANTING TO YIELD ON 263 MONROE COUNTY FARMS 



IN 1913 



lower than the average of this region would have given more than average 

 yields. With the least seed and fertilizer, the shallowest-planted fields 

 gave the highest yields. Since the potato soils of this region are heavier 

 than those of either Long Island or Franklin and Clinton Counties, and, 

 in fact, are rather heavier than ideal potato soil should be, this gives further 

 evidence that potatoes should be planted shallower on heavy than on light 

 soils. With an increase in the value of manure and fertilizer, and an 

 approximately constant amount of seed used per acre, an increase in depth 

 of planting was accompanied by decreased yield on fields planted deeper 

 than 2 inches. 



The importance of depth of planting as influencing yield in Franklin and 

 Clinton Counties is shown in table 73. The average yields in this region 

 increased with the depth of planting, down to a depth of 4 inches. A part 

 of this increase must be attributed to an increased use of seed and fertilizer. 



