LUTHER BURBANK 
while the bush-like mountain form is very hardy. 
Being an unusually ornamental evergreen the 
mountain variety should be extensively planted 
in cold climates. 
I am inclined to believe that the golden ever- 
green chestnut and the chestnut oak could be com- 
bined by crossing. If so, remarkable trees could 
be produced. 
As yet, however, I have not been able to attempt 
this hybridization, nor, indeed, have I as yet 
hybridized the golden chestnut with the ordinary 
chestnut, for the reason above stated. 
I have made tentative efforts, however, to cross 
my early bearing hybrid chestnuts with the Cali- 
fornia tanbark or chestnut oak, Quercus densi- 
florus. 
Notwithstanding the wide difference between 
the species, numerous nuts were produced and it 
seems probable that these were hybrids. As to 
this, however, I cannot be certain until the seed- 
lings have come to maturity. 
The object of such wider hybridizing is, in 
particular, merely to test the possibilities of cross- 
ing a plant that shows a high degree of inherent 
flexibility. But it is also desirable for practical 
reasons to accentuate the variability and to carry 
forward further series of experiments in selective 
breeding. 
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