Worcestershire Record No. 25 November 2008 p. 8

Mike Averill

Hartlebury Common has always been an enigmatic place for naturalists and from the mid 1800’s people such as Edwin Lees made many visits to the site. The possibility of visiting the common had the promise of the sorts of flora and fauna associated with acid rich poor soils of lowland heath. In addition a great attraction was the presence of a bog and pool where permanent water enabled specific plants to flourish such as sphagnum mosses, round-leaved sundew, bladderwort, marsh violets and cotton grass. Such a place in the Worcestershire context would also have meant the chance to see rare water beetles and scarce dragonflies.

Heathland is a transient feature in the landscape and reports from visitors over the last 100 years give testimony to the fact that a succession to a more tree covered heath has taken place as land use has changed and less grazing has occurred. The bog itself has shown periods of drying out since the early 1900’s and this threatens its future as permanent water is essential to most aquatic plants and animals. Possible reasons for the drying out are likely to be changes in groundwater abstraction, the reduction in water catchment area caused by the building of the housing estate at one end of the bog in the 1960’s, and the seasonal variation of rainfall. These, plus the changes of small scale digging in the bog have led to a grass dominated area with intermittent wet patches. For the bog to thrive it needs the supporting water table to fluctuate at a level which ensures the bog has some water even when the weather is dry. This means that when the weather is wetter, the area can be temporarily flooded.

Since 1974, when groundwater levels were first monitored by the Environment Agency and its predecessors, it has become apparent that there have been 15 years when the bog had no surface water at all. The problem tends to be compounded by the fact that the years cluster in 5 to 7 year blocks, the worst periods being in the 1970’s, the 1990’s and the early part of this century. Looking closely at the graph it can be seen that if the level in the bog is plotted over the last eight years, the period from early March 2003 to early March 2007 was completely dry. Since June 2007, the bog has had two successive wet years and a visit this year would have made the visitor think everything was normal as dragonflies hawked and darted over the bog. After many years of debate, there is a possibility of doing something to ensure there is permanent water in the bog, let’s hope it won’t be too long before these plans come to fruition otherwise Hartlebury will have been one of the last bogs in Worcestershire.