42 LUTHER BURBANK 



ment of a variety, properly selected, that would 

 retain the good qualities of the Persian nut, 

 and combine these with the size and prolific bear- 

 ing of the Royal. This has later been accom- 

 plished with striking results. 



Hybridizing Methods 



But, of course, whoever undertakes improving 

 the nut trees must be content to make haste 

 slowly, for the black walnut has not as yet been 

 made to bear when very young, as the chestnuts 

 and some strains of the English walnuts 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 pis- 

 tillate parent. 



Of course, one cannot make sure that some of 

 the flowers will not be self -fertilized, and this is 

 wholly unnecessary, for by planting a large 

 number of the nuts any good judge can deter- 

 mine from the appearance of the seedlings 

 which ones are hybrids. Also where the trees 

 grow close together there are sometimes natural 

 hybrids, though this was not generally known 

 when I made my first experiments in 1875-1880. 



