that the present great tree plantations of the 
Middle West cover areas which were grasslands 
only 130 years ago and that almost all of the 
trees planted on the highways, in parks, country- 
side, streets and yards of America are of the 
bottomland varieties—elms, sycamores, pin oaks, 
etc. Consequently, he believes that these bottom- 
land trees “have been growing on the drier sites 
for such a short time that we may hardly expect 
them to be fully adjusted.” We concludes from 
this that ‘the ravages of phloem necrosis may be 
due, in part, to the fact that we have been attempt- 
ing to use a bottomland tree on what had very 
recently been grassland and that “Chestnut Blight 
and Oak Wilt are merely an expression of incom- 
plete adjustment to a changing environment.” In 
any estimate of life there are two factors both of 
which are difficult to judge—the factor of inherit- 
ance and the.factor of environment. An old adage 
applies here—"‘the boy can be taken from the 
farm, but the farm can never be taken out of 
the boy.” 
The Augustine Ascending Elm shows a very 
high resistance to Elm tree diseases. The chief 
pathologist of the Illinois Natural History Survey 
Division at the University of Illinois has after 
three years of attempts succeeded in getting grafts 
of wood infected with phloem necrosis to “take” 
on some young Augustine Ascending Elms in his 
greenhouse; the trees continue to live. The same 
experiment has been performed with Dutch Elm 
disease in the Park Department of another large 
city, and the young trees there continue to live. 
Immunity to disease or to insect pests is not the 
claim for the Augustine Ascending Elm. If would 
seem however, that this new Elm is nature's 
answer to the challenge of changing environment. 
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