Chimney straps are not the best idea, as it may kill plant material above the strap. Think of a tree like your arm: If you put a strap too tight onto your arm and leave it there, it cuts off the circulation. It's a rough analogy, but you get the idea. If you want to use a mast, I would get a lightweight mast, attach the mast to a plate with some U-bolts, and then use 4 big lag screws and go directly to the trunk. The tree will heal around the lag screws and it should be pretty solid.
Moleculo
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