jajkola9-stack Is it possible to somehow adjust the radius of the tree search?
No, not yet.
jajkola9-stack I have a tree very close to me, but he runs far away to dig it up
The way TreeBot's tree selection works is a bit different from how you might expect. It doesn't decide based on straight line-of-sight distance, but instead uses pathfinder cost (meaning, estimated time it would take to actually walk there).
So if there is a closer tree that it's not going to, chances are that either the pathfinder sees that tree as unreachable or the tree exceeds the size limit (for example, TreeBot can't cut large oak trees yet).
jajkola9-stack and is it possible to somehow combine Killaura with Treebot to kill monsters?
Yes, that should work. It might miss some mobs like skeletons (since it won't walk up to them unless they happen to be in the way of a tree), but generally enabling TreeBot + Killaura means that it will defend itself while cutting trees.