rotate a tree at the base

so im trying to make it so i can “cut down” trees made in tree creator, but the pivot point is set to the center of the trees, if i made a tree in max i could manage this easily by changing the pivot, but to my knowledge there is no way to do this in unity and i dont think i can export the mesh. I need the rotational pivot to be right at the base of the tree, where it meets the ground. how would i go about this?

As i know, you can only change mesh pivot point in 3d modelling software. An alternative way would be creating an empty gameobject, child the tree to this empty gameobject. Position it correctly so the gameobject transform is just like you said “at the base of the tree”, so now if you rotate the main gameobject, the tree should be rotation as you wish.

I’d still use 3d modelling software to change the pivot points, because using unneeded gameobjects (which are quite expensive for engine, but I’m not 100% sure) is just additional work for the computer. Plus, if there will be many trees, I wouldn’t suggest this even more.