Geysers that act like natural wells? Also, it could spew water every now and then, and whenever it spews, there'd be a chance of some kind of forage-able/curiosity lying around it?
Thickets could have a thicket bushes, that would act like trees. Take a seedling, grow it via the usual tree growing methods, and plant it. Anyone walking in the "area" of it, would be slowed to a crawl, and constantly get thorns in their feet if they don't have shoes on. Obviously you can just chop it down to get rid of it.