In North Dakota it is legal to drive on unposted land to set up, that includes pulling a trailer. If the land is posted, of course, you will need permission from the land owner or renter. A word of advice, we have had lots of rain today and more coming tonight, I would advise you to ask permission before driving in any feild posted or not this weekend. We had a wet last week of early goose season here, and a lot of feilds got rutted up by hunters. Needless to say alot of No Hunting posters have gone up since. If the land isn't posted, ask around, you will find out who owns it.