Collision between static geometry that never changes, is also pointless for the server to be dealing with, since the client computers can handle that themselves, and this is the situation you currently have. Unless of course, players can randomly chop down trees during gameplay, then you will have a much more elaborate situation on your hands, and I sure hope it’s a lumber jack simulator, because tree chopping had better be an essential part of the game that you just can’t do without, to justify how much work you will need to do to allow this functionality and still have the game run fast for all clients.
Glad to help you further, but I’ve pretty much told you all I can based on what I know about what you’re doing so far. Feel free to ask questions or provide me with more info.