We harvest dead fallen trees and sell it for firewood.It's been said that anything within the easmemt can be cut up and taken away without permission

You refer to an easement over land.  I am guessing that is a road right of way but I suppose it could be a utillity easement.  The holder of the right of way or easement may have the right to cut down trees, but cut trees, as well as naturally fallen trees within an easement will belong to the property owner, not easement holder, unless the easement otherwise provides.  (An easement might, for example, require the easement holder to remove any trees or branches it cuts down.) A road commission or easement holder may tell you that you can remove the trees, or at least that it does not object, but it may not have the authority to give that permission.  In my opinion, in most cases the trees belong to the land owner, even if within an easement.  Most land owners would welcome your removing them but some will want to keep the dead trees for their own use or natural decay.