What is the color of the tall trees?
The trees are brown.
    src        edge_attr  dst
0     0       growing in    4
1     0  to the right of    7
2     1           behind    4
3     3  to the right of    7
4     4      in front of    1
5     7           eating    4
6     7   to the left of    8
7     7   to the left of    3
8     7   to the left of    0
9     7   to the left of    9
10    7   to the left of   14
11    8  to the right of    7
12    9  to the right of    7
13   10  to the right of   13
14   11   to the left of   12
15   12  to the right of   11
16   12  standing behind   14
17   13   to the left of   10
18   13  to the right of   15
19   14    standing near   13
20   14      standing in    4
21   14  to the right of    7
22   14       grazing on    4
23   15   to the left of   13