Is there any way to separate them and take different routes?

Is there any way to separate them and take different routes?

They will crawl into the middle of the tree to chop it down.

Can i see your config file? 
Are you on custom map?
Did they spawn like this?

About tree, you can add it in ignore list in config 

I am using a custom map.

RoamingNPCs.json

Try to enter /rnpc init and then /rnpc vis and check where will they spawn and what route will they take

Having a group all doing the same and going the same route may happen, if they spawn at the same time at nearly the same spot. It also happens, if you use the new "SpawnsDatabase" option as respawn mode, and only have one spawn point. I mitigated it by defining a couple of slightly different spawn points. Best would be a spawn-cooldown of about 10 seconds between two spawns, so the first already ran away when the next spawns.