Tooth traps are a workable solution. You can run up and plant them very close to him because he is so slow and stops every 4-5 steps for a few seconds. It works but it takes a long time and lots of running around. They have an insanity aura that is pretty damaging to the brain so you gotta keep moving. Three or more traps at least.
A very easy way is to lead them into red butt beefalo herds, but again it takes awhile to lead them there if the herd isn't close by.
Planting pine cones work to get them to stop chasing you and turn back into a tree. But the next day they will get up and start walking around again. They won't be hostile anymore, but they can still wander into your camp (eventually) and their aura drives you insane. They are mostly an aggravation at that point. If you use the pine cone method then eventually there will be many of them wandering around all over the map so it is definitely better to kill them if you can.
IMHO they aren't much of a threat. Honestly I think they are the silliest mobs in the game. I think they have way too much health. I usually just turn them off or set them to less when I feel more adventurous. Also they are more useful to have when you play smaller maps because there aren't as many evil trees available in the forest to get the living logs from and so you need to get them from the treeguards. On a big map they are just a pain to deal with.
If you are up for cheating, put your cursor over it then enter the following in the console:
TheInput:GetWorldEntityUnderMouse():Remove()
which will simply delete them from the game.