Now THAT'S a field clearing pile

I saw several piles this weekend in Harvard that I thought were probably field clearing piles. I cannot be sure but I would not argue these with someone who said they were "agrarian". Let's look at this pile:
Note that it is:

• isolated
• right at the edge of a plowable plateau
• looks casually spilled over the side.
  
• runs all along that edge of the plateau
• lies at the angle of repose.
  

However, the rocks are mostly the same general size and that suggests rock sorting. It could be an old platform pile fallen down the slope. But on the balance I think it is from field clearing.

Here is another:


This pile is:

• somewhat too conical, almost angle of repose
  
• the rocks were too young looking (although it was just cleaned of debris recently)
• it was right at the edge of a nice flat arrable field.
• it was isolated with no similar piles nearby (most times a rock pile by itself is not credible as ceremonial)

However I am not sure it is agrarian. I want to "contrast and compare" these piles with other piles, which I am going to do in a subsequent post.