It is not a field boundary, not a windbreak, and not the remnant of a vanished building. It is a tree-ring, a deliberate ornamental planting associated with the designed landscapes of large estates, intended to create visual incident across an otherwise open prospect. This one measures somewhere between thirty and thirty-five metres in diameter.

The land was formerly part of the Westport House estate, and the planting is old enough to have been recorded on the Ordnance Survey six-inch map of 1838, where it appears as an unenclosed circular ring of trees. By later map editions it had begun to read as a sub-circular enclosure, the trees presumably having grown denser and the ring more defined. Westport House itself was developed through the eighteenth century by the Browne family, and the surrounding demesne was laid out with the kind of considered landscaping fashionable among Irish and British landed families of that period. Tree-rings of this sort were a relatively common feature of such designed landscapes, placed on slopes or ridges where they could be seen from the house or from carriage drives, functioning as eye-catchers in the manner of follies or ornamental copses. A second tree-ring of the same type lies roughly two hundred and thirty metres to the west, suggesting the two were conceived as part of a coherent scheme across the hillside rather than as isolated plantings.