Remove decorations when placing entities or tiles.
Normally you would not build a house/road and leave the bushes below it, would you? :)

Ghosts will not remove decorations before the bots dont build the ghost.

Decorations take up at around 50% of (my) savegame-filesize. With this mod, it is possible to slightly reduce the savegame size - if you need ALL decorations gone, go for the undecorator mod.