Things You'll Need
Instructions
Locate the Oblivion data directory folder. The default location of this folder is C:\Program Files\Bethesda Softworks\Oblivion\Data.
Search the data folder for the tree mod used. The folders or files you will be removing to uninstall the mod depend on which tree mod was installed in the first place. For example, if you have the mod "Autumn Trees" installed, you would have placed the meshes and texture folders in the data directory, along with a "PTAutumnTrees.esp" file.
Delete the corresponding tree mod files from the data folder. Referring back to the Autumn Trees mod, you would remove the meshes and textures folders that had been placed in the data directory upon installation. Additionally, the "PTAutumnTrees.esp" file would be removed. Any tree mod in the directory marked as an ".esp" file should be removed when uninstalling the mod. This completes the uninstall.