I live in NJ and I am preparing an enclosure for an arrival that I will hopefully be getting this week. The question I have is this - can oak leaves or sassafras leaves be harmful to redfoots? I am trying to put in an assortment of plants, grass, etc to make it interesting. I thought that piling leaves would help retain moisture and add to the enclosure. Thanks!!!

Your oaks are different from my oaks out west. But our oaks have a high oil content I believe and I'd imagine they taste terrible.
Most likely, oak leaves that fall to the ground would be dried out so I can't imagine there would be much danger.