LUTHER BURBANK 
But, even so, there is no dearth of material. 
America is richly stocked with forest trees. More- 
over these represent, so the geological botanists 
assure us, a flora of very ancient origin which has 
shown its capacity to maintain itself through suc- 
cessive eras during which there have been tremen- 
dous climatic changes. 
It follows that our native forest trees have in 
their heredity the reminiscence of many and 
widely varying environments. And by the same 
token they have capacity for variation, and there- 
fore afford exceptional opportunity for diversified 
development. 
It is not necessary here to analyze in great 
detail the qualities of the different groups of forest 
trees. A brief summary of the characteristics of a 
few of the more important groups will serve to 
suggest the abundance of native material, and to 
give at least an inkling as to what may be ex- 
pected, in the light of what was revealed by the 
experiments with the walnuts, as to possibilities of 
development of the different tribes. 
Of course the great family of cone-bearers 
stands in the foreground, represented by many 
species, and known as the timber trees that give 
us the pine lumber which has everywhere been the 
chief material for the carpenter, and an important 
foundation material for the cabinet-maker. 
[172] 
