Dungeness: The Open Pits

21st September 2007, Friday

Dungeness is distinguished by having a number of natural wet hollows in the shingle, that over several centuries have accumulated deep deposits of peat. These support a number of plants that are rare in Kent, infact these natural shingle wetlands are very rare globally. After several decades of neglect, which resulted in much willow invasion, work started on restoring the open unshaded habitats in 1997. Annoyingly very low water levels in 2005 and 2006 resulted in the loss of bog pondweed Potamogeton polygonifolius one of several plants that reappeared following the first round of scrub clearance. This summer’s rain has restored water levels fully and on 19th September it was pleasingly almost impossible to wade into pits that are normally accessible in the summer. There have been good shows of plants typical of these pits this summer such as cotton grass Eriophorum angustifolium, marsh cinquefoil (below) Potentilla palustris, and nationally scarce marsh fern Thelypteris palustris.
marsh cinquefoil
These pits are one of those cross-over interests on Dungeness where biology merges into the study of geomorphology and history. The age of the peats can be determined by radio-carbon dating, and the pollen remains show what plant communities were growing here in the past. Interestingly Dr Martyn Waller has shown that at the base of one of these pits there are numerous fragments of cannabis. Evidently the water was being used to soak hemp in the middle ages which was subsequently turned into rope. To safeguard the geomorphology, management of the pits has to avoid disturbing the buried deposits for future studies.
cotton grass