In a basin at Littleton near Thurles, County Tipperary, in south-central Ireland at 140 m above sea level, a series of deposits-first open-water mud, then fen peat, and finally raised-bog Sphagnum peat-developed, beginning in Late Glacial time and continuing to the present day. Pollen counts were made throughout the deposits, and the pollen of all plants thought to have grown on the drier ground surrounding the basin were included in the pollen total. The total diagram thus makes clear the dominance of herbs in Late Glacial time, interrupted by the Allerod phase when Betula expanded. When Postglacial time began, bushes quickly displaced the herbs, and the bushes in turn gave way to Pinus and Corylus. Quercus and Ulmus established themselves later in the Boreal period, and in the following Atlantic period Pinus shrank markedly, and Quercus, Ulmus, Alnus, and Corylus formed a closed deciduous canopy which overshadowed the herbs.