Within Fernworthy Forest, on the slopes of Tom's Hill, this is an area of granite clitter, cloaked in moss. A visit in 2016 revealed forestry work had damaged some of the moss, exposing the white granite and lessening the appeal which is ironic because if it weren't for the cover of the forest, the moss would not be there in the first place.
However, consulting Crossing, this was never once the case, before the forest was planted. He writes "Turning south-westward we shall make our way to Hemstone Rocks, situated on that part of Long Ridge known as Tom's Hill, passing a few hut circles as we proceed. Near to us, on the L., is the South Teign, and on the further side of that stream the slope of Assacombe Hill."
John Chudleigh, writing in 1892, makes a brief reference to Hempstone Rocks when talking about a collection of antiquities that stretch away from Batworthy possibly to Scorhill Circle on page 77 of his little book. We read "Here this important series of monuments connect very large settlements - Metherell, Fernworthy and Hempstone Rocks colonies at one end, the colony around Kestor at the other."
A more recent visit in 2019 revealed that much of this clitter has been left undisturbed, for now.