The peat deposits at Howden Moss, Upper Teesdale, have been examined stratigraphically and pollen analytically. The present state of the bog in described and pollen diagrams are presented for three sites. The results show that peat formation had begun by the early post-glacial period, zone V, and growth apparently continued up to the present time. The area was colonised by birch trees early in its development. Open birchwood persisted on the site during the expansion of mixed oak forest into the valley bottom. This dichotomous situation continued until the birch wood on the fell was replaced by blanket bog communities. The late-glacial rolict flora which is associated with some sites in Upper Teesdale is not found at Howden Moss. The pollen record provides no evidence for its past existence in the area
