The first place to turn is to your landowner.
As a leaseholder, you don't have the same rights as the landowner. If there is an easement and restrictions on putting up gates, you landowner probably knows about them.
Your actions in closing the road can affect your landowner, so you need to communicate with the landowner before you do anything like that.
If the NFS has an easement, that doesn't necessarily mean the public does. The landowner's deed probably has information about any easements listed on it. You may be able to post it against trespass with signs even if you can't put gates up.
If the landowner can't help you, then try this route:
Info about easements *** cick here *** See page 41 "Unrecorded Easements".
Here's the email page for the Department of the Interior Bureau of Land Management contact page. They might be able to email you any easement info they have:
Contact page *** clck here ***
