446 80VTHEBN FIELD CROPS 



some cultivating implement in the open furrow. It is 

 usually better for the beds to be formed several weeks 

 before the date of transplanting, so as to permit the soil 

 to be settled by rain. The beds should be kept covered 

 with a loose layer of soil and free from crust and vegetation 

 by the repeated use of a light harrow. 



To produce the largest yield, the depth of plowing should 

 be considerable, and deep plowing should probably be 

 the rule where the crop is to be used as stock food. How- 

 ever, the market prefers a rather short potato, and this 

 shape is favored by rather shallow plowing; that is, to a 

 depth of not more than 5 inches. 



421. High and low beds. — While level tillage can be 

 practiced for sweet-potatoes set out late on sandy, well- 

 drained soil, it is probably advisable for the planting, as 

 a rule, to be done on beds; however, these should be 

 pulled down by the use of the harrow until elevated only 

 3 or 4 inches above the water-furrows. Planting on low 

 ridges affords a warmer, more perfectly drained soil. 

 The extremely high ridges sometimes seen add greatly 

 to the cost of cultivation, and unless the season be very 

 wet, high ridges do not materially increase the yield. 



422. Tillage. — Cultivation should be given whenever 

 a crust begins to form, or when the first appearance of 

 young weeds or grass makes it necessary. Tillage should 

 be shallow. The most satisfactory implements are those 

 forms of one-horse cultivators equipped with small points, 

 so as to be rim as near as possible to the plants without 

 covering them with soil. A scrape or any other imple- 

 ment doing shallow work is also suitable. Just before 

 each ciiltivation, if the vines have begun to run, they 



