62 THE POTATO 



nary conditions large seed should be used, (2) on good 

 soils with heavy fertilizing^ small tubers and closer 

 planting is advisable; but that the small tubers shall be 

 the progeny of large tubers grown on well-cultivated 

 and fertilized soil, to prevent degeneration. Tubers 

 which are small because the parent plant had not suf- 

 ficient vigor to produce any larger are worthless for 

 seed. 



At Arkansas Station 1 whole tubers 2 inches to 3 

 inches in diameter yielded 18 per cent, more than small 

 whole tubers ^ inches to i} inches in diameter, and 

 large cut tubers 15.8 per cent, more than small cut 

 tubers. At the Ontario Agricultural College 3 the 

 largest yields for four years in succession were from 

 planting large seed. Sets weighing one-sixteenth of 

 an ounce and having one eye yielded, on an average, 

 for the four years, 44.2 bushels, while two-ounce sets 

 having one eye averaged 177.4 bushels per acre, and 

 intervening sizes of sets yielded in proportion to their 

 size. As the result of eight years' careful experi- 

 ments, this station advises that large tubers be cut into 

 pieces weighing about two ounces each for sets. 3 



J. C. Arthur, 4 of Indiana, conducted an elaborate 

 set of experiments for three }^ears to ascertain the rela- 

 tion of the number of eyes on the seed tuber to the 

 product. He found that within certain limits the yield 

 will increase with an increase in the weight of the set, 

 and that the exact number of eyes per cutting is rela- 

 tively unimportant. With tubers of the same weight 

 and variety the number of shoots does not perceptibly 



1 Ark. Bui. 50, p. 28. * Ont. Agr. Col. Report, 1898, p. 156. 



s Ont. Agr. Col. Report, 1902, p. 126. * Ind. Bui. 42. 



