Actually the way:
1. Go to the folder with Dayz (steamapps/common/DayZ)
2. Find the Addons folder
3. Look for files starting with "plants2..." and "structures.."
4. Move\Remove(it is Better to leave so that I can then bring them back) in another place files plants2_Bush.pbo, plants2_Clutter.pbo, plants2_misc.pbo, plants2_Plant.pbo, plants2_Tree.pbo(To the grass and trees).
Files on structures..." to remove the building
5. Go in the game, go to the server and enjoy)
We see through the trees\building. You can walk through.