Interesting photo essay. Do you have any idea what else grows in the field with those lumps? The lumps look rather like they might be mounds of compose that were set around to be spread, but then, for some reason were left as dropped.

I’ve seen mounds of compost set out in yard and gardens, ready to be spread around evenly. I’ve never seen them left untended, so I have no real idea they’d end up like the lumps you photographed.