The soil of Blakes Hill was created by glacial movement. The area is full of stones making it very difficult to farm. Each spring the farmers of Northwood would gather up the rocks that would be pushed to the surface by the freeze thaw. The stones would be used for house foundations and stone walls. On Blakes Hill there would always be a surplus. Rock Dumps are located throughout Northwood including the Rollins Rock Pile on Blakes Hill Road.