What is the moss on?
The moss is on the tree.
    src        edge_attr  dst
0     0  to the right of    7
1     0   to the left of    6
2     1   to the left of    4
3     1  to the right of    7
4     1   to the left of   11
5     2  to the right of    5
6     3  to the right of    7
7     4  to the right of    1
8     4   to the left of   11
9     4   to the left of   10
10    4  to the right of    7
11    4               on    1
12    5   to the left of    2
13    5  to the right of    7
14    5   to the left of    9
15    6  to the right of    0
16    7   to the left of   12
17    7   to the left of   14
18    7   to the left of    5
19    7   to the left of    4
20    7   to the left of    0
21    7   to the left of    1
22    7   to the left of    3
23    7   to the left of    9
24    7   to the left of    8
25    8  to the right of    7
26    9  to the right of    7
27    9  to the right of    5
28   10       resting on   11
29   10  to the right of    4
30   11  to the right of    4
31   11  to the right of    1
32   12  to the right of    7
33   14  to the right of    7
34   14               on    3