i was on a site that said that only 3 riding areas are open in the winter but i was at the hopkington-everette resevoir in dunbarton nh this past weekend and it wasnt on the list and it was open well certain trails were open to certain vehicles. we also had our registration checked out by the law so we were abviously allowed there so how do we know whats open and whats closed without traveling there do you need snow cover or how does it work thanks for the info