Try to make sure the bees get morning sun, if you can.  In the summer, both
bees and beekeeper benefit from afternoon shade (in my experience).
 
It would be better if the trees were deciduous, because then you would have a
sunny spot in the winter and a shady spot in the summer.  Oh, well, you can't
have everything.  If you can, trim away branches (or trees) directly to the
south of the hives, so that the winter sun can get to them as much as
possible.  Leave the trees to the west; they'll provide shade for those long
summer afternoons.
 
Windbreaks are real nice, particularly if you live in a windy spot (last
summer, my husband left the 1-ton in neutral after he parked it....the wind
was strong enough to start it rolling across the barn yard--windbreaks are
real useful here.)
 
It doesn't matter what color you paint your hives.  Light colors are probably
easier for the bees to keep cool in summer.  Some people paint each of their
hives differently; they claim that the bees can use the different color tones
and shapes to identify their hives better.  They say it cuts down on drift.
 
Have fun!