You can't change the topography without changing
residence, or antenna site, so I wouldn't worry about
the hill some distance away.
As for the trees, just be sure you have a clear column
for raising and lowering the antennas.
One of the things I learned..the hard way...is that tree
branches that aren't in the way when there's no wind...
they whip around and up and down, and WILL snag a nearby
antenna in a serious storm. I lost a 40m beam in the
backwash of a hurricane, up in VT, of all places...not only
did the branch snag and bend an element, it snagged a guyline,
and whipped hell out of the tower.
So...tree clearance is critical.
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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