LUTHER BURBANK 



afforded the only feasible means of introducing 

 good qualities into the fruit of the thomless 

 dewberries. 



Now the work of development took on aspects 

 closely comparable to those that we have already 

 reviewed at length in the development of orchard 

 fruits. It was necessary to bear in mind such 

 items as increased size of fruit, good flavor, firm 

 flesh, and time of ripening — all of these being 

 matters regarding which the thornless berries 

 were defective. 



Improvement Through HYBRiDizma 



Of course there was no dearth of material with 

 which to effect hybridization. 



The dewberry is merely a trailing variety of 

 blackberry, and it crosses readily with all other 

 species of blackberry. 



I had at hand any niunber of blackberries 

 bearing fruit of the finest quality. There would 

 probably be no difficulty whatever in producing 

 hybrids between the little thomless berry and 

 the Lawton blackberry, for example, or my new 

 Himalaya berry, or any one of a dozen others. 

 And some of these would give, among varying 

 seedlings, a certain member that would bear ex- 

 cellent fruit. 



But, imfortunately, when such crosses were 

 made, it was at once apparent that the thorny 



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