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[N0GV]

Trees can cause absorption and de tune an antenna. As a general rule a tree can cost you between 0 and 3dB of signal power. The further from the tree the conductor is the lower the loss. Try to use two trees to support a dipole with the ends held to each tree with rope and an insulator to keep the high E field ends of the dipole well away from the trees.

If you are using a vertical you might find it useful to tie it in the center of a rope spanning the space between 2 trees and allowing it to hang to the ground mounted feed point.

Another issue is pattern modification, that is a place and try sort of optimization.  Put it up and use a field strength meter with a couple of watts to see the approximate pattern.

Enjoy,

Grover

[US7IGN]

Try to use two trees to support

This advice will make sense if you find trees made of steel or concrete that will stay still in the wind. Unfortunately, the most common trees grow in my area, which will immediately tear such fasteners.

[N0GV]

Use pulleys with weights to tension the ends. Keeps constant tension regardless of tree motion if the pulleys aren't seized up. Do it all the time....

Grover

[K0UA]

If you are using a vertical you might find it useful to tie it in the center of a rope spanning the space between 2 trees and allowing it to hang to the ground mounted feed point.

I do this with my 40/20/15 vertical. The rope is called a catenary.  Think of it as a "sky hook".  It is just a support to hold the vertical wires up. I use Stainless steel chain quick links to pull a string thru to pull up the vertical wires.  That way you can easily lower and raise the vertical wires any time you like. Or even replace them without lowering the catenary rope. As long as you don't break or lose the pull string. Obviously the feed point is near the ground on a post that is high enough to support the elevated tuned radial wires. This works very well and keeps your vertical away from the trees and in the clear.

[N0GV]

Absotively correct!

Grover