LUTHER BURBANK 
I must not attempt to speak except in a general 
way of the other members of the great tribe of 
conifers, the merits of most of which, as orna- 
‘mental trees, are familiar to every garden and 
landscape architect. 
There are some scores of genera and some 
hundreds of species of conifers but the varieties 
are too numerous and too intricately blended for 
accurate computation. 
No other single region has so many forms of 
evergreens, and ones that show such wide range 
of variation, as the Pacific Coast region. It has 
been estimated, indeed, that there are as many 
species of conifers in California as in all the rest 
of the world. 
But the conifers of one kind and another grow 
everywhere throughout the colder regions of the 
northern hemisphere, some of them making their 
way also to parts of the South. 
Every one of them is an object lesson in the 
possibility of plant variation; for as a class they 
represent a modification of leaf form of the most 
striking character to meet the exigencies of a 
changing environment. 
Time was, doubtless, when the ancestors of 
the conifers had flat, spreading leaves like the 
leaves of other forms of vegetation. But when the 
climatic conditions changed, the pampering influ- 
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