Each grove has its own subfolder. The folders are named with the Zone ID.
Each grove subfolder contains a list of text files titled in a x000y000.txt format. These files contain a list of props. Refer to Scenery File Format.
The X and Y coordinates of a particular tile are derived from the zone's page size. Typically 1000 game units (most official zones) or 1920 (actual terrain tile size).