226 The Potato Crops 



sides of 2 X 4 supports, with 1 x 4-inch material to pro- 

 vide air space between the bins ; circulation is also provided 

 by starting the bins 4 inches above the floor. 



Varieties. 



The purpose for which the crop is grown determines very 

 largely the variety, and the variety will determine the care 

 necessary; e.g., the Red Bermuda will grow in almost any 

 soil and under very adverse conditions of climate and mois- 

 ture, but the quality cannot be compared to that of the 

 so-called yams. In the South a soft sugary sweet potato 

 is desired. In -the North a firm dry tuber is wanted. 

 Spanish, Sugar, Barbadoes, Nancy Hall, Triumph, Dooley, 

 and Hyman are popular far South. Nansemond and Jer- 

 sey are prized for the North. The Vineless, a variety with 

 short tops or vines ("vineless" meaning "not running," 

 or "bushy"), is now a popular kind. As with the Irish 

 potato, careful attention should be given to breeding. 



In the United States, the sweet potato rarely sets seed. 

 In fact, it does not often bloom, although blossoms may 

 appear late in the season under favorable conditions. The 

 production of new varieties depends on tuber-selection and 

 the appearing* of mutations or sports. 



The Sweet Potato Plant 



Ipomoea. Gonvolvulacem. Twining herbs, shrubs, even trees, 

 largely of tropical countries, of about 400 species. 



I. Batatas, Poir. Encyc. vi, 14. 1804. (Convolvulus Batatas, 

 Linn. Sp. PI. 154. Batatas edulis, Choisy, Convolv. Or. 53. 

 1S34.) Sweet potato. Tuberous-rooted perennial with long 

 running tops, juice luillty : stems prostrate, slender, extending 

 many feet, rooting, angled, mostly with sparse thin hairs: 

 leaves alternate, long-stalked, thinly hairy or glabrous, exceed- 



