Freshwater Habitats Trust Oxfordshire Fens Project
Oxfordshire's calcareous, alkaline, valley-head, groundwater-fed fens
On 22 April 2018
"It has been so warm these jet ants (Lasius fuliginosus) are amazingly active on their nest tree in Cothill NNR and my fly guardian species, the rare associatred Milichia ludens, is out flying round the tree!"
Photos taken by Judy
at Cothill NNR, part of Cothill Fen Site of Special Scientific Interest (SSSI) and Special Area of Conservation (SAC)
Judy's interest in fens dates back to her PhD (completed in 1977) on the vegetation history of three alkaline fens in Scotland (now National Nature Reserves). She has studied and recorded the plants, invertebrates and fungi, as well as the water quality, of Oxfordshire alkaline fens since 2006 and is regularly contacted by the local branch of Natural England and by Oxford City Council about fen management. Her particular research interests are in Cothill Fen SAC, a site of European importance, and the Lye Valley SSSI.
These fens, which are some of the most botanically diverse habitats in England, typically occur in valleyhead and hillslope locations. They are mainly irrigated by groundwater discharge from springs and seepages, with the water table close to the surface all year round.
An excellent poster created for an event covering groundwater-dependent ecosystems held in February 2013, organised by The Geological Society, provides detailed information.
Lye Valley fens
Alkaline Fens & the Importance of the Lye Valley SSSI Fens within Oxfordshire and Nationally/Internationally, Judy Webb 2014
Photos by Judy Webb of important plant species found in these Oxfordshire fens:
Sedges and grasses
BBOWT Wild Oxford Project: fen restoration work in Chilswell Valley
Abingdon Green Gym members working at Cothill (National Nature Reserve) on 6 December 2014 - photos by Judy Webb
Meet the Soldierflies of Cothill Fens, article by Judy Webb, May 2015
Bog bean, Menyanthes trifoliata Fruits of Black Sedge, Carex nigra Marsh helleborine, Epipactis palustris
Photos by Judy Web
Photos by Judy Web