LUTHER BURBANK 



nut has not as yet been made io bear in childhood, 

 so to speak, as the chestnuts and some strains of 

 the English walnut now do. But in this regard 

 also there would doubtless be rapid improvement 

 under selection. 



The actual method of hand-pollenizing is very 

 simple. Nothing more is necessary than to break 

 off the flower bearing branch, just at the right 

 time, and shake it over the flowers of the pistillate 

 parent. 



Of course one cannot make sure that some of 

 the flowers will not be self -fertilized, but by plant- 

 ing a large number of the nuts, it will be possible 

 to determine from the appearance of the seedlings 

 which ones are hybrids. Also where the trees 

 grow close together, there are sometimes natural 

 hybrids, though I was not aware of this when I 

 made my first experiments, in years 1875-1880. 



When I made my first experiments at hybrid- 

 izing the walnuts, I planted the seeds of the entire 

 tree. In the rows of seedlings, I could at once 

 determine which ones were hybridized, as these 

 grew far more rapidly than the others, besides dif- 

 fering notably in general appearance. 



My first experiment was made with two black 

 walnuts, and it was the success of this that led me 

 to attempt to hybridize the Persian and California 

 walnuts the following year. The hybridization in 



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