LUTHER BURBANK 



cise record of the hybridizations after they become 

 very complex. 



For a good many years, to be sure, I kept accu- 

 rate check on the various crosses. 



The names of the parents used in an original 

 hybridizing experiment were alvv^ays recorded. 



Later, as the cross became more complex, large 

 numbers of species being utilized, I attempted 

 short cuts by using numbers and letters on my 

 labels, the key to these being recorded in my plan 

 books. 



This worked very well for a few years more. 

 But there came a time when an experiment with 

 a single strain of roses had been carried through 

 so many generations that the traits of ten species 

 or more would be combined in an individual. 



At this stage I abandoned the numbers and 

 letters, and contented myself with a general knowl- 

 edge of the principal ancestors in the pedigree of 

 any new variety, distinguishing the new variety 

 itself by a temporary name for purposes of further 

 record. 



Thus I have, for example, grown upward of 

 two hundred thousand seedlings from the Crim- 

 son Rambler poUenated with all the ordinary roses 

 that are under cultivation in California. The pol- 

 len of only a few of them proved effective. But 

 here and there a rose like the Empress of India or 



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