Wytham Woods is a mixed deciduous forest in southern England. It covers approximately 400 ha, which is a relatively large woodland for the UK and includes a range of different soil types and management histories. Wytham is owned by Oxford University and is used by the Centre for Ecology and Hydrology (CEH) as a long-term monitoring site in the UK Environmental Change Network (ECN). CEH operates a flux tower on the site, measuring stand-scale carbon and water fluxes; a canopy walkway gives access to the leaves of canopy trees, and several studies of tree ecophysiology have been carried out there. A network of small (10 m x 10 m) ECN forest-monitoring plots is distributed across the site, and a 1-ha plot forms a focus for carbon-dynamics studies, including soil processes and tree growth.