Bimey. Not good.

I hope they're field clearance piled up relatively recently, and not old-time packing stones.

Seriously though, the sheep did a good job drawing attention to that stone on Wrynose Pass that Kammer posted. It looks a tad polished at sheep level.
http://www.themodernantiquarian.com/post/38450
The question is: Does the rubbing away of old lichen constitute serious damage (as at Avebury too), in an archaeological sense? I don't know enough about it myself, and just wondered what the reasons for concern along this line at various sites was. I do realise the lichen is extremely old, but why the fuss from the archaeologists?
Cheers,
TE.

The first picture suggests the field had recently been taken out of arable production. The second shows the field well overgrazed - 'poached'. Female sheep have sexual needs too - the idea is that Rock Art and 'lesser' monuments are protected, by agreement, through DEFRA's Environmental Stewardship Scheme. (But the man has to apply first). A fifty pence through-the-gate box would change things. I'm curious to know the diameter of the perforation, in the stone, to see whether it correlates with an even number - perhaps five - of Thom's Megalithic Inches.