Some Experiments of I^uther Burbank 



in cultivation. The English walnut has usually 

 five leaflets, the black walnut fifteen to nineteen. 

 The first generation hybrid has eleven, with a 

 fragrance to the leaves that no original walnut has. 

 This tendency or trait is just as real as any other. 

 The American walnut {Juglans nigra) and the 

 California black walnut (/. californicd) are closely 

 related species and when hybridized yield fruit of 

 very large size and in enormous quantities. 



Descendants of hybrids usually revert to either 

 one or the other parent or break up in all direc- 

 tions. A cross of the eastern black walnut {^Jug- 

 lans nigra) with the California nut (/. californica) 

 yields a hybrid which is a very great grower. 

 From the seed of this tree a surprising variety of 

 mutations are developed, not only resembling 

 every possible combination of both parents but 

 numerous strange forms. In fact, among about 

 two thousand seedlings now alive, almost every 

 type or form of walnut foliage may be found. 

 There are startling variations in size, form and 

 number of leaflets, in the size of the plant, in the 



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