LUTHER BUR BANK'S "WORK 



37 1 



photograph is introduced to give the reader some idea of the work neces- 

 sary to produce a satisfactory new race of berries. " Of the 40,000 

 blackberry X raspberry hybrids of this kind ' Phenomenal ' is the only 

 one now in existence. From the other 25,000 hybrids, two dozen bushes 

 were reserved for further trial.*' 



An astonishing result of the hybridization between the black walnut. 

 Juglans nigra, used as the pistillate parent, and the California walnut, 

 J. calif ornica, staminate parent, are walnut trees which grow with such 

 an amazing vigor and rapidity that they increase in size at least twice 

 as fast as the combined growth of both parents. Many tremendous 

 growers are got in the first generation, but in the second there are in- 









T . 





Rhodanthe naglesi, improved in size and color by selection only. 



eluded some of the most rapidly growing trees, perhaps, in the world. 

 This hybrid has clean-cut, glossy bright green leaves from two to three 

 feet long with a sweet odor like that of apples, but it produces few 

 nuts. Curiously enough the result of hybridization by using the pollen 

 of nigra on pistils of calif urn ica produces in abundance large nuts of a 

 quality superior to that possessed by either parent. 



The famous Shasta daisy is the result of a multiple crossing between 

 an American and a European species of field daisy and then between 

 these hybrids and a Japanese form. The fragrant calla, known as 

 * Fragrance/ is descended from a single individual found by Burbank 

 while critically examining a block of Little Gem calla seedlings. He 

 was surprised in this examination by a fragrance resembling that of 

 violets or water-lilies; as be had long been seeking a fragrant calla, 



