Planting 147 



planted in hills. Growers in all the important potato- 

 growing sections find it practicable, by modern tillage 

 methods, to keep weeds subdued in drills as well as in 

 hills. The prices received for potatoes from sections in 

 which drill culture is general are higher than from those 

 where hill culture is mainly used. City markets demand 

 medium-sized tubers, and pay better prices than for the 

 coarse and overgrown tubers raised in hills. When 

 machine diggers are used, digging costs the same when 

 either method of planting is employed. With hand 

 digging, the larger number of hills to the acre under drill 

 culture takes more time to dig than with hills and may 

 reduce the acreage by limiting the amount which can be 

 dug before freezing weather. The constant improvement 

 in the manufacture of diggers is producing machines that 

 will dig in very stony soils. 



The general rule for spacing hills is to vary the number 

 of hills to the acre according to the yield which may be 

 expected. As the distance apart decreases, the weight of 

 the individual hills and the size of the tubers is reduced 

 and the total yield to the acre is increased. The cost of 

 planting and digging may be increased. Digging close- 

 planted hills is rather expensive. The smaller size from 

 close planting brings higher prices in city markets. An ex- 

 treme case of close planting is that in the island of Jersey 

 where potatoes are planted 12 by 16 inches, or over 

 32,000 hills to the acre. With very rich soil and hand 

 tillage, a yield averaging over 400 bushels to the acre is 

 secured, even when dug for the early market, while still 

 growing. The ty^Q of the potato variety affects the 

 spacing. The common Rural or Blue Sprout type sets 

 fewer tubers to the hill than the Green Mountain or 

 White Sprout type and should be planted closer on that 



