Practice of Plant Breeding 



hybrid walnut, for instance, planted in 1891 and said 

 to have been 80 feet in height and 2 feet in diameter 

 in 1906. The timber is also said to be of excellent 

 quality. Such trees would solve all our forestry pro- 

 blems. His stoneless plums, obtained from an old and 

 useless French variety, would also be valuable, and so 

 with many of the others. 



In forming his Alhambra plum he is said to have 

 combined seven different varieties, which were grafted 

 on old trees and so brought into bearing at the earliest 

 possible moment. 



One can only hope that the spineless edible cactus 

 with which he experimented for many years, and for 

 which he crossed many different American species, will 

 really prove hardy and useful in desert and half-desert 

 places. 



During 1906, in the first six months of their life, 

 some of these cacti produced 47J lbs. per plant which, 

 as they were planted in rows 5 feet apart and 2 J feet 

 distant, has been estimated as a yield of 90 tons per 

 acre. Even if this should prove unsuited for cattle- 

 feeding, it will surely be of value, perhaps, for the pro- 

 duction of alcohol. It is unnecessary to describe in 

 detail the Shasta daisies, the Cannas 7 inches across, 

 and the huge Amaryllis and other flowering plants which 

 have been produced by him. 



In breeding lilies he is said to have used 500,000 

 plants in one single test."^ 



He was not, however, always successful. In his 

 efforts to improve the Californian dewberry, he crossed 

 it with brambles, with rasps, strawberries, roses, cherries, 

 apples, and pears and never got any satisfactory result. 

 Hundreds of Nicotianas were crossed with Petunia, but 



* This account of Luther Burbank's life and work is entirely derived from 

 books and publications. The author has never seen any of his novelties. 



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