FRUIT BREEDING 265 



He emphasized the value of crossing as a means of producing 

 improved forms for he believed this method was more rapid than 

 Von Mons' selection practice. 



American Pomology. Throughout the nineteenth century 

 American pomologists made great progress in the improvement 

 of fruits. While many American named varieties occurred as 

 chance seedlings, others were the result of careful breeding. The 

 strawberry and grape are examples of fruits in which many of 

 the varieties are a result of controlled breeding. Selection and 

 crossing both played important parts in the improvement of 

 varieties. Hovey was one of the best known of the early straw- 

 berry breeders who worked during the first half of the nine- 

 teenth century. 



The production of improved American varieties of grapes well 

 illustrates a common method of the production of new fruits. 

 Old World grapes did not succeed in the greater part of the United 

 States, as European varieties proved very susceptible to diseases, 

 particularly mildew. The production of American varieties from 

 native wild species gave us many of the cultivated types. Some 

 of the best of the early varieties arose as chance seedlings. Con- 

 cord was thus discovered by Ephraim W. Bull and introduced 

 about 1853. It has been frequently used as a parent for the 

 production of the improved forms. Some improved forms have 

 resulted from crosses between native and European varieties, 

 Delaware being generally thought to have been so produced. 



With the plum, as with the grape, the native American species 

 have furnished the source from which a large part of the American 

 varieties have been produced (Wight, 1915). Several wild 

 species have been used and frequently the varieties which have 

 proved best adapted to a given locality have been produced 

 from the wild form which is native to the same region. 



SOME CONSIDERATIONS OF FRUIT BREEDING 



Fundamental laws of heredity furnish the same foundation for 

 a development of correct breeding technic in the fruits as with 

 other crops. There are, however, some factors which, modify 

 breeding methods. For example, a single tree takes up con- 

 siderable field space and thus has a greater value than a single 

 plant of wheat or corn. In comparing varieties and clonal lines 

 the question of soil heterogeneity must be considered for this is 



