Depth to Plow 



The seed-bed should be deep; therefore, it is necessary to plow the 

 ground to a depth of eight or nine inches. If the soil is sandy, it is not 

 necessary to plow so deep, or if the subsoil is gravel, deep plowing is not 

 advisable. 



The object of a deep seed-bed is to give the roots an opportunity to 

 easily penetrate below the line where the tubers form, which is usually 

 not more than four inches below the surface. If the seed-bed is only 

 four or five inches deep and the bottom of the furrow is inclined to be 

 hard, the roots, seeking the course of least resistance, will spread outward 

 instead of downward, and in case of drouth, the plant suffers, and if deep 

 cultivation is practiced, the roots are apt to be pruned. If, however, 

 the ground is plowed deep and is subsequently made loose and mellow by 

 discing, the roots take the downward course, and when they reach the 

 bottom of the seed-bed, they have stability to penetrate into the deeper 

 subsoils where they usually secure an abundance of moisture. 



If a hard-pan exists which is so compact that water cannot percolate 

 into the deeper subsoils, it is advisable to use the subsoil plow, which 

 simply cuts a gash, admitting air and moisture into the deeper subsoils 

 which tend to mellow the hard-pan. It is not necessary, however, to 

 use the subsoil plow oftener than once in four or five years. 



In order to secure the best results, the ground should be thoroughly 

 disced before plowing, in order to secure a compact contact between the 

 bottom of the furrow and the seed-bed, to mix thoroughly throughout 

 the seed-bed any trash that may be on the surface, and to pulverize all 

 lumps. 



Depth to Plant 



The depth to plant depends upon the character of the seed-bed, the 

 nature of the soil and the probable supply of moisture. 



In heavy, wet lands where rains are frequent, the potatoes should not 

 be planted more than three or three and one-half inches in depth, but 

 if the soil is light, it is necessary to plant them deeper. In semi-arid 

 regions, potatoes should be planted deeper than in humid sections. 

 Extensive experiments have demonstrated that potatoes planted four 

 inches deep in average soils with an average rainfall made a yield four 

 and one-half per cent greater than those planted to a less depth, and 

 eight per cent more than those planted in a greater depth. It has been 

 demonstrated, however, that potatoes planted deep gave the best 

 quality and the largest per cent of merchantable potatoes. 



Fertilizers 



An acre of potatoes consumes from seventy to eighty pounds of nitro- 

 gen, from ten to fifteen pounds of phosphorus, and from eighty to one 

 hundred pounds of potassium. The crop also requires from five hun- 



