My QTH in FL is in a sub-tropical forest environment where most of the trees
keep their leaves all year long and there have sap running the year round.
My 15 meter Yagi stack is 33/66/99/132 feet high and is about 50 feet from a
sub-tropical forest which is about 80 feet tall. I have never felt it had
any effect on the antennas' effectiveness. The forest is located in the
direction of EU through South America. No numbers to put out, just my gut
TowerTalk mailing list