(2) For the purpose of subsection (1) of this section, the boundaries of "enclosed" land may be indicated by wire, ditch, hedge, fence, water or by any visible or distinctive lines that indicate a separation from the surrounding or contiguous territory, and includes the established and posted boundaries of Indian reservations established by treaties of the United States and the various Indian tribes. [Amended by 1959 c.318 §1; 1971 c.580 §1; 1973 c.723 §83]