Tree Diseases

[KDav97]

Am looking for info on any tree which has experienced severe decline in
the last fifty years - ie, Elms, Cornus florida, Ash, etc.  I need to know
which trees and or shrubs have been widely affected and any other info I
can get on this.  This is for publication.  If you would like to assist,
please email me at KDav97 at aol.com.