Lag bolts in a tree - OK or bad idea??

[davefr]

I'd like to attach a satellite mount to the trunk of a Doug. Fir. (about 5' up the trunk and the tree is about 24" diam.)

Attachment would be 2 lag bolts about 3-4" long.

It seems like people have been attaching things to trees since the beginning of time but is there a proper way to do it?? (ie should I use stainless steel or hot dipped screws). Any other considerations?

 

[Kneejerk Bombas]

If you just put a lag bolt into a tree, that's a small injury, no problem. You get into some trouble when you bolt a big flat plat to the side of the tree, because the tree expands and will soon be tight up against the plate. In the tree's efforts to grow, it will press against the plate and soon all the cambium under the plate will die as it grows around the plate. It would be like you made an injury the size of the plate on the trunk of the tree.
If left undisturbed, the tree will likely grow completely around the mounting plate and be fine. A better solution would be to put some spacers that hold the mounting plate away from the tree, so it can grow in diameter and even be adjusted out in time.