56 The Sweet Potato 



than 10,000 bushels of tubers, selling the plants to 

 smaller growers at a good profit. This specialization 

 has not only been made remunerative by ingenious and 

 industrious planters, but, because of the economy pos- 

 sible in handling large quantities, has been of real 

 service to the smaller planters. The larger number of 

 farmers who plant less than an acre usually find it 

 more convenient and economical to purchase their plants 

 than to grow them at home. Planters growing more 

 than an aCre usually prefer to prepare their own seed- 

 bed and grow their sets at home. From 6 to 8 bushels 

 of seed potatoes are required to produce enough plants 

 to set an acre at one drawing. Usually three or four 

 drawings may be made, 3 or 4 bushels of seed producing 

 enough plants for an acre. It requires from 8,000 to 

 10,000 plants to set an acre (Plate III). Although as 

 many as 4,000 plants have been produced from a single 

 bushel of seed, the average production ranges from one- 

 third to one-half this number with three or four draw- 

 ings. The question of proper seed selection with refer- 

 ence to the influence on yield and quality of the field 

 product and the control of disease is now known to be 

 of more importance than was formerly thought. 



SELECTING SEED (l. E., TUBEKS FOK PEOPAGATIN'G) 



Although the value of individual hill selection has 

 been fully demonstrated with the common potato, ex- 

 perimental data available on the same subject with the 

 sweet potato is not so complete. The commonly fol- 

 lowed practice of using the culls and stringy tubers for 

 seed has been the subject of much controversy with 

 little conclusive data substantiating either side of the 

 argument. However, practical growers have long 



