194 FIELD CROPS FOR THE COTTON-BELT 



keeps clearly in mind a mental picture of his ideal type, 

 and in making his selections from year to year does not 

 deviate from this type, there is no question but that a 

 gradual improvement can be accomplished. The fact 

 that many of our oldest and best varieties of corn have 

 been produced by this method is evidence of its value 

 when properly conducted. For example, in 1825, J. L. 

 Learning, of Wilmington, Ohio, began selecting the best 

 ears of his field for his seed corn. He mixed the seed and 

 planted it with no attempt to study the progeny of individ- 

 ual ears. By this method he finally improved his strain 

 to the degree that it became widely known and was im- 

 ported into Illinois. There the selection was continued by 

 the same method followed by Learning. At present, the 

 Learning variety is considered one of the best yielding 

 sorts for that state. James Riley, of Thorntown, Indiana, 

 working with the ordinary white corn of Indiana, selected 

 seed with the idea of diminishing the number of barren 

 stalks and of ears of minor value in his field. The result 

 of his work is the famous Boone County White, probably 

 the most popular variety of corn in Indiana and Illinois. 

 Reid's Yellow Dent, a variety widely grown in the corn 

 belt, was produced by mass selection. The objection to 

 this method is the slowness with which improvement is 

 accomplished. 



237. Pedigree selection. It has been found that 

 two ears of corn of similar appearance, and coming from 

 plants of apparently equal value, will not necessarily 

 produce progeny of equal value. It often happens that 

 one ear will produce from 20 to 40 per cent more than the 

 other when used as seed. In other words, the hereditary 

 qualities of the two ears may differ markedly, and since 

 the aim of corn breeding is the improvement of hereditary 



