LUTHER BURBANK 
the problem of re-forestration throughout the 
whole of the United States. 
Perhaps the eucalyptus may be made more 
hardy by hybridizing and selection. If not, we 
must take to heart the lessons it gives—in common 
with the hybrid walnuts—as to the possibility that 
a tree may show almost abnormal capacity for 
rapid growth and at the same time may produce 
lumber of the hardest texture. 
Hitherto it has generally been supposed that a 
tree of rapid growth would as a matter of course 
produce soft timber. The hybrid walnuts and the 
various eucalyptus trees serve to dispel that 
fallacy. 
NaTIVE MATERIALS 
The one fault of the eucalyptus, its inability to 
stand extreme cold, is likely to be shared by other 
trees that are imported from the southern hemis- 
phere or from sub-tropical regions of our own 
hemisphere. 
Although, as just suggested, it may be possible 
to overcome this fault through selective breeding, 
a long series of experiments will doubtless be 
necessary before this can be accomplished. In the 
meantime we shall be obliged to place chief 
dependence, in all probability, upon our native 
stock of trees, hybridized perhaps with allied 
species of Europe and northern Asia. 
[170} 
