A cypress knee is a distinctive structure forming above the roots of a cypress tree of any of various species of the subfamily Taxodioideae. Their function is unknown, but they are generally seen on trees growing in swamps. Some scientists have thought they may help in oxygenation to the tree's roots or assist in anchoring the tree in the soft, muddy soil. See photos for more detailed condition.

This was probably cut during the building of lake Marion in the 1940's as a lot of cypris trees were cut down in the construction of the lake.