362 FIELD CROP PRODUCTION 



not need to be sun sprouted before planting. The tubers 

 which have been sun sprouted are usually cut with one 

 sprout to a piece ; the growth is very rapid and a higher 

 percentage of stand is secured than from unsprouted seed. 

 The tubers thus grown keep better, shrink less, and are 

 much slower in sending out the white sprouts than ordi- 

 nary seed. 



384. Northern grown seed. While it is often stated 

 that northern grown seed is much superior to " home " 

 grown seed or that grown south of a given point, yet a 

 number of experiments have not shown this to be the 

 case. If the seed of a given variety is of equal maturity, 

 free from disease, and of equal quality in other respects, 

 little difference in results will be noticed. 



385. Rate of planting. Various quantities of seed are 

 used per acre, depending on the distance of planting, 

 somewhat on the variety in question, and method of cut- 

 ting the seed. Twelve to fourteen bushels of seed is a 

 common quantity used. Medium size tubers are selected 

 and cut two eyes to the piece. Seed pieces are dropped 

 every twelve to fifteen inches in the row, and the rows 

 thirty-three to thirty-six inches apart. In some sections 

 they are planted in hills and cultivated both ways. The 

 seed pieces are covered three to four inches deep. 



386. Fertilizers. In order to secure the largest possi- 

 ble yield of any crop, there should at all times be a suffi- 

 cient- quantity of moisture and plant food. It is as great a 

 disadvantage to a plant to be stunted at any period of its 

 growth as it is to an animal. But the amount of artificial 

 plant food which a crop requires can only be determined 

 by experimenting on every farm. We know that potatoes 

 use a large amount of potash in growing, but many soils 

 (clay soils especially) are oftentimes so rich in potash 



