you know it!! the field edges have piles of rock feet deep. The flat flag stones are all limestone - its not too far down, the Allegheny plateau was the bottom of an inland sea. Also the land in the southern tier of NY was carved out when the glaciers receded - so in addition to our own bedrock not too deep - we get a lot of round, water polished igneous rocks like granite that were dropped when they melted. Sometimes huge 1000 lb round granite rocks are found - you see them around here a lot in peoples front yards - they are interesting for sure. We don't have any huge ones on ours - but a lot of bowling ball sizes and smaller. They wreck a Brushhog let me tell you!!Triple, that field has probably had rocks pulled out of it yearly for decades....