Another factor that appears to be supporting evidence of this
Hypothesis-- maples are hosts
of DED, is the evidence that in the southern USA of around starting
with Arkansas that the
elms have fared nicely relative to DED disease free. Whereas the
northern states of elms,
of course there are alot of maples and of course Canada's national
tree is the maple.

I do not know if a detailed history has been kept of the sweeping of
DED across the USA.
Detailed as to die-off of elms, where and when for the past century of
DED. But from a
overall observation, it appears that DED has eliminated the elm of
american and rock-elm
from nearly all the northern states and Canada. Whereas the southern
states have not had
that devastation.

Of course, that is not proof, for to have proof we actually need to
find out how maples interact
with the beetles and fungus of DED. Perhaps it is an interaction with
the fungus that affects maples themselves-- verticillium wilt. And
maybe there is a common microbe that is beneficial
to both the DED fungus and the wilt fungus that the prescence of
maples allows for a resident
population of DED. I do not know the connections and am just
Hypothesizing a connection based on observations. It maybe something
analogous to that of apple cedar rust where the presence of the two
species allows the disease.

Archimedes Plutonium
http://www.iw.net/~a_plutonium/
whole entire Universe is just one big atom
where dots of the electron-dot-cloud are galaxies