gehajake,
I have started protecting all trees that go past 5'. However, I am doing barbed wire with 4 t-posts because I still have to weed and prune the trees and repair drip emitters that good chewed up etc.
It is a fair bit of effort and cost to do it that way. Do you have a good wire ring design that I could make semi-removable for when I need to work directly on the tree base area?
