178 SUCCESSFUL FARMING 



the southern tier of the Northern states. The only exception is in the case 

 of midsummer planting with the aim of securing a crop in the fall. Farther 

 north the planting may be later in the spring, although the tendency in 

 recent years has been away from June planting. 



The depth of planting depends upon the character of the soil and the 

 variety. Where an early crop is wanted, the planting is shallow, but for a 

 main crop in loose soils the depth should be at least three inches below the 

 dead level of the surface. 



A planter does more satisfactory work than can be done by hand, 

 dropping the seed in a more direct line. The width between rows may vary 

 from thirty to thirty-five inches and the distance between the seed pieces 

 in the row should be sufficient to require about fourteen bushels of seed per 

 acre. This is a surer rule than any fixed number of inches, as much depends 

 upon the cutting. 



Cultivation. — A soil that is sufficiently retentive of moisture for the 

 potato usually inclines to become more compact than is desired. The 

 preparation of the soil and the planting compacts some of the ground 

 beneath the surface. A few days after the planting is finished it is good 

 practice to give a very deep and close cultivation, the shovels being guided 

 by the furrows made in covering. Later the weeder or harrow should be 

 used to level the ground and kill all weeds so that the potato plants will 

 come up in a fresh, clean soil. Close and deep tillage should be given when 

 all the plants are above ground, and later the cultivation should be more 

 shallow so that the roots of the plants will not be unduly disturbed. Level 

 culture enables the grower to keep the maximum amount of moisture in 

 the soil, but dependence upon mechanical diggers has led practical growers 

 to ridge the rows and, when the growing is on a large scale, this is the only 

 practical method of controlling grass and weeds. Cultivation should 

 continue until the vines fill the middles, and the last cultivation should be 

 given by a light one-horse cultivator that will slip under fallen vines. The 

 early cultivation should keep the soil loose and later cultivation should 

 keep the surface well mulched with loose earth and should prevent any 

 growth of weeds. 



Diseases. — The number of virulent potato diseases is increasing in 

 this country, and the grower should study the latest bulletins from his state 

 experiment station. He will be informed regarding the formalin treatment 

 for the seed before planting, that gives control of some diseases. All 

 potato seed should be given this treatment, which consists of soaking the 

 seed for two hours in a solution of formaldehyde made by diluting one pint 

 of 40 per cent formaldehyde in 30 gallons of water. This should be done 

 before the seed is cut and under no circumstances should scabby seed be 

 planted without this treatment. 



Close examination of the seed pieces when cutting is an aid. Mechani- 

 cal cutters are not advised and partly for this reason. All tubers showing 

 discoloration of any sort should be rejected. 



