LilRedMG, I think that may have been TMI.
You tell us that you aren't digging a cathole if you use a tree for back support during toileting. Hikers, like most of the world, find that the deep knee squat improves their aim and efficiency during toileting. This is not done as efficiently holding on to anything other than your knees as you complete the task, usually holding a portion of the seat of your pants to keep them out of the target zone.
My understanding was that urine belongs on the ground and not on plant material as deer and other critters will be attracted to the salt. You won't find my urine on your tree.