LUTHER BURBANK 



different well known varieties or races of plums. 

 The mixed pedigree of the product is recorded 

 in this motley galaxy of offspring; but details as 

 to all the parental crosses, tracing back along an 

 experimental search of thirty years duration, are 

 not to be had. The original parents used in the 

 first cross are of course known; but successive 

 generations deal with tens of thousands of seed- 

 lings. So it was impossible for anyone who was 

 carrying out, as I have been, not less than three 

 thousand different plant breeding experiments 

 each year, involving in the aggregate not fewer 

 than six thousand different species, to trace 

 accurately, much less to record, each and every 

 cross-fertilization among the myriad blossoms of 

 my orchard. 



Yet a chance hybridization might by good 

 fortune effect precisely the needed combination 

 of qualities to give me a fruit that had eluded my 

 most earnest efforts at systematic breeding. 



Very often, to be sure, I can judge from the 

 result what the racial strains most probably were 

 that were blended to produce the new hybrid. 

 But even this is not always possible, and not a few 

 among the thousands of new varieties of plums 

 that have originated in my orchard are of untraced 

 and untraceable pedigree, at least as regards some 

 of their strains. 



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