Denham Lock Wood

It is a wet woodland and fen site which is skirted by the Frays River. The main trees are alder and crack willow in the wetter areas, and elsewhere oak and ash with a shrub layer of hazel. In winter wildfowl are visible and in spring many flower species. Invertebrates include red cardinal beetles, banded demoiselles and the rare and protected Desmoulin's whorl snail. The balsam carpet moth was added to the list of British species when it was found at the Wood in 1955, and it is only known at one other site in Britain.

Access is by a footbridge across Frays River from Frays Farm Meadows, which is also an nature reserve managed by London Wildlife Trust, south of the Wood. Access to the Meadows is by a stile on the east side of the Grand Union Canal at Denham Lock.