THE SWEET POTATO. 63 



toes into three groups, having 'round or entire foli- 

 age,' 'shoulder foliage' and 'split or lobed foliage.' 

 He says, 'If this foliage system is taken in connection 

 with a short description of the color of the tubers 

 and of the vines, there is scarcely a variety which 

 cannot be distinguished from all other varieties.' 



' 'This system has been applied at several stations, 

 yet it would be quite impossible to recognize some 

 varieties as known in one section by descriptions 

 given of them according to the foliage system in 

 another section if the name were omitted. So 

 strong are the influences tending toward diversity 

 that the writer is convinced that no system of classi- 

 fication can demonstrate much value until the sup- 

 posed varieties are all brought together and propa- 

 gated imder uniform conditions for several years." 



Before going further into the subject, one might 

 well ask if there is any urgent necessity for the 

 classification of the varieties. The writer's reason 

 will be given later. In the following are quoted 

 the opinions of others who are practical farmers or 

 are otherwise interested in the subject: 



In Farmers' Bulletin 129, p. 38, Mr. Nesbit, a 

 practical sweet potato grower of Maryland, gives 

 some suggestions for future experiments. In regard 

 to improvement of varieties he has this to say: "If 

 all the varieties or supposed varieties for which 

 merit is claimed should be collected and cultivated 

 for several years under favorable conditions and 

 with a system calculated to develop excellence, 

 planters might, at the conclusion of such a course, 

 be able to select from a few varieties of marked 

 characteristics such as give promise of special use- 

 fulness to them. The value of such work in estab- 

 lishing varieties and determining their relative 



