The USDA PLANTS Database does not record this species as wild in Allegheny County, but there are a lot of things the USDA doesn’t know. There was a substantial patch here in the Allegheny Cemetery, obviously not planted deliberately, though it may well be descended from White Stonecrop planted elsewhere in the cemetery.
Like our other species of Sedum, this one is a low succulent plant with starry flowers. It is easily distinguished from Goldmoss (Sedum sarmentosum) by its white flowers held aloft in clusters on stems well above the plant. Wild Stonecrop (Sedum ternatum) also has white flowers, but in arching branches intermingled with leaves rather than in clusters above the plant.
This plant was not well established enough in Gray’s time to make it into his Manual, but our description here should make it easy enough to identify.