What's the fence surrounding?
The fence is surrounding the field.
    src        edge_attr  dst
0     1  to the right of    2
1     2   to the left of    1
2     5       grazing in   12
3     5  to the right of    7
4     5               in   12
5     7         touching    2
6     7   to the left of    5
7     7  to the right of   11
8     8      surrounding   12
9     9   to the left of   11
10   10   to the left of   11
11   11   to the left of    7
12   11  to the right of    9
13   11  to the right of   10
14   12    surrounded by    8
15   13               in   12
16   14               in    3