GeoGraph - photograph every grid square

Wall dividing a change of vegetation

The likely reason for the vegetation being different on the left and right of the wall is that different amounts of sheep inhabit the two sides. On the right the sheep are eating everything except grass and a bit of bracken so I guess there are more of them per acre. On the left of the wall I think the dark green and brown areas would be mixed bilberry and heather.
As long as sheep graze on moors we will not get a truly natural range of plantlife and all that it supports. I suggest that at least 5% of moorland in England and Wales should be cleared of sheep.