Driftwood is a feature of beach maps. It is not known if it replenishes over time. It cannot be harvested for wood, nor can it be smoothed over. Driftwood can be removed by uilding a onstruction such as a r or ad on the tile, which will transform the tile into an ordinary tile of the base allrock type. Note that you cannot see the rock type of a driftwood tile while the driftwood is present. Driftwood can sometimes appear when mining out frozen seas in glacial biomes.