BERRIES AND GARDEN FRUITS 



application of this principle enabled him to pro- 

 duce a large number of his most important new 

 varieties of all kinds of plants. He decides in 

 advance what qualities he wishes to perpetuate 

 and what ones he wishes to eliminate, and by 

 selecting among large numbers of seedlings he 

 is enabled to secure the ideal plant that he has 

 in mind. 



But it must not be supposed that Mr. Burbank's 

 success is due merely to the recombining of desired 

 fruit characters already present in one parent or 

 the other. On the contrary, such segregation and 

 recombination of traits constitutes only the begin- 

 ning of his task. This does, indeed, supply him 

 with varying material with which to work ; but as 

 a rule he would not produce a fruit of commercial 

 value did he not extend the experiment by se- 

 lective breeding among the individuals that have 

 the desired quality in the most pronounced degree. 

 Line breeding them intensifies these qualities ; so 

 that, for example, the Burbank white blackberry 

 is snow-white, whereas its so-called " white " an- 

 cestor was dull brownish-white, and at the same 

 time it has the excellent qualities of the Lawton. 



THE THOBNLESS BLACKBEEBY 



It was through application of the same princi- 

 ples that Mr. Burbank was enabled to develop his 

 wonderful thornless blackberry, perhaps the most 

 important of his plant developments in this par- 

 ticular field. Anyone who has had experience of 



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