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secure as many of the roots as possible. Other shoots 

 readily develop after the first ones have been broken 

 oif and three or four crops may be secured. The 

 later shoots, however, are weaker and not so satis- 

 factory for planting purposes. This plan is fre- 

 quently modified somewhat in planting large areas. 

 A small area will be planted from plants secured as 

 described above and planted very early in the season. 

 By time to plant the main crop these vines will 

 have made considerable growth and are cut and 

 placed in the soil where the plant is expected to 

 develop from the green stem cuttings. These green 

 cuttings root readily and give excellent results. 

 This plan sometimes avoids some of the serious 

 diseases common to this crop. 



In level culture the planting distances are usually 

 30 to 36 inches between the rows and from 18 to 24 

 inches in the row. When planted on ridges the 

 rows are usually from 30 to 40 inches wide with 

 the plants from 12 to 18 inches apart in the rows. 



Cultivation should be started as soon as planting 

 is completed. Spiked tooth cultivators are used as 

 often as necessary to maintain a thorough mulch and 

 until vine growth prevents further tillage. Little 

 hand hoeing should be necessary where proper 

 preparation and careful cultivation have been given. 

 Sweet potatoes are usable as soon as they are of 

 sufficient size, but their quality is low and the yield 

 poor. The high prices secured often justify early 

 digging however. Where the crop is intended for 

 storage, digging should be delayed as long as pos- 

 sible in order that the maximum growth may be 

 secured and the tubers become thoroughly mature. 



In harvesting the roots are usually plowed out 

 with a special form of plow, carrying two roller; 



