BURBANK'S WAY WITH TREES 



shown by a few at least of the progeny having 

 this complex heritage. 



Suppose, for the sake of illustration, that one 

 of these second-generation hybrids is exceedingly 

 productive and bears a nut of fine quality but 

 lacking in size. The next step of the experiment, 

 then, would be to hybridize this individual with 

 the Japanese chestnut, one of its grandparents, 

 which bears very large nuts. 



The offspring of this cross will probably have 

 some representatives that combine the exceptional 

 qualities of one of their parents with the large 

 size of the other. 



A moment's reflection will make it clear that 

 where four species are in question it is possible 

 to unite their strains in an almost endless number 

 of combinations in successive generations. This 

 was precisely what Mr. Burbank did in the case 

 of chestnuts from three continents. He blended 

 their strains this way and that, noting results, 

 and being guided thereby in making new tests; 

 until presently he had quite the most remarkable 

 chestnut trees that had ever been seen, including, 

 among others, the dwarfed forms to which refer- 

 ence has already been made. 



But how, it will naturally be asked, could ex- 

 periments of this intricate character be carried out 

 in one man's lifetime, when we are dealing with 

 a tree that ordinarily does not begin to bear fruit 

 until it is several years old? 



The answer gives us an insight into another 

 very remarkable feature of the experiment. ( ' It 



[209] 



