As Cannibal said, its all about the species of tree. Also yout cordage comes into play, it can burn into the inner layers of the tree. Most people recommend 1" tree straps b/c there is less force put on the tree because it is widened out over that 1 inch. I would not recommend using line ( zing it,lash it, paracord, climbing rope, etc...) to wrap around the tree because it can cause damage. ALWAYS USE TREE STRAPS.