It appears on the Ordnance Survey twenty-six-inch plan surveyed in 1911 as a neat raised oval shape, the kind of mark that tends to attract the attention of archaeologists, suggesting enclosures, ring forts, or older earthworks folded into the landscape over centuries.

When investigators visited in 1975, the bank was still faintly legible at ground level, but it did not read as an antiquity in any conventional sense. A tree-ring is a designed landscape feature, typically a circular or oval earthen bank planted with trees to create a deliberate visual effect within a formal or semi-formal demesne setting. They were fashionable additions to Irish and British country house grounds in the eighteenth and nineteenth centuries, serving as ornamental punctuation in the parkland rather than as functional enclosures. The oval at Knockanbaun fits this pattern well enough, and the demesne context of Whitehill House makes the interpretation plausible. By the time of the 1975 inspection, whatever trees may once have stood on the bank had long gone, and the earthwork itself has since disappeared entirely at ground level.

What remains is essentially a cartographic ghost, present on the 1911 map and then slowly erased, leaving only the question of what stood there and for how long.