222 LUTHER BURBANK 



Inasmuch as the thornless bushes, of whatever 

 generation, will breed true to thornlessness if fer- 

 tilized among themselves, it is obvious that each 

 thornless generation constitutes a fixed race, pro- 

 vided the plant experimenter does not elect to 

 disturb its fixity by a new hybridization. 



The result, up to date, is that after twenty- 

 four years of selective breeding along these lines, 

 the descendants of the little North Carolina dew- 

 berry (who are descendants also, of course, of 

 various and sundry berries of more aristocratic 

 bearing) constitute a race of blackberries grow- 

 ing on large, well-shaped, spreading bushes that 

 are always absolutely thornless. The fruit itself 

 is a large, handsome, glossy blackberry, of ex- 

 cellent flavor, profusely clustered a fruit that 

 makes inviting appeal to all and which will exact 

 no penalty in the way of scratches from those who 

 gather it. 



The story of the thornless blackberry is thus 

 told at length because the development of this 

 fruit quite eclipses all my earlier work with the 

 blackberries, and makes the record of the de- 

 velopment of the thorny varieties, however 

 excellent their fruit, seem an almost archaic 

 performance. 



It must be recalled, however, that the present 

 thornless blackberries of superior quality could 



