In an MMORPG:

Is it typical or feasible to store the coordinates of every tree, bush rock.. etc in the server side for collision detection?

If so, what would be a feasible way to store such a huge number of coordinates (data structures and such, performance issues handling)?

If not, is this type of collision detection done entirely in the client side, with the server not checking at all?

Or is there a middle ground, with the client checking collision and server verifying? If so, how would the server verify the same without keeping the coordinates in the server as well?