To my knowledge there is no rules regarding on the # of wheels allowed for usage as a ATV at Uwharrie. Keep in mind that in the early 80s there was only 3 wheeled ATVs for the most part. I road a ATC 200x at Uwharrie back then as well as my Nissan 720. Today ATVs can have as many as 6 wheels. Wear a helmet and remember that a 3 wheeler is very lite on the front end.
I like the old 3 wheelers. I grin every time I see the pics. of the 3 wheelers on trail markers at Tellico. Goes to show how old some of the trail markers are. Be safe on the 3 wheeler.