On Wednesday our volunteers helped clear invading birch scrub and Rhododendron saplings from our valley mire. This started the discussion (mainly by Alison) of whether it was a bog or a mire. In reality it can be both, since a bog is a type of mire! Wikipedia says 'A bog is a mire that accumulates peat, a deposit of dead plant material—often mosses, and in a majority of cases, Sphagnum moss.'
This unique and fascinating part of the reserve is a haven for specialist plants and insects, and is rich with a soft Sphagnum moss. The mire has formed due to a geological fault where rain water seeps through the ground until it hits impermeable clay, then emerges from the valley-side, creating a mosaic of wet pools amongst the heather.
Our 'valley mire' can be classified as a 'valley bog'.
We also spotted a fascinating plant sticking up out of one of the pools. Some further research (by Keith) revealed this to be Bog Beacon (Mitrula paludosa) - see below. The ID was confirmed by Martin Allison. The species is confined to acid bogs and is quite rare in the south east. Martin informs us it usually appears every spring in the mire at Tudeley Woods, although Martin hadn't managed to find it so far this season.
Thanks to the hard work our our volunteers Alison, Jane, Gareth, Matt, Charlotte and Keith, a good section of this important habitat is now cleared of scrub and saved from the encroaching Rhododendron.
Thanks to Alison for bringing this quandry of nomenclature to our attention! :D Although Valley Mire does sound better than 'Valley Bog'...