The land in Vallée des Vaux is very dear to the Trust, as it was here, in 1936, that its founding members recognised the urgent need to prevent the destruction of the valley through inappropriate development. A wooded côtil was in danger of being sold for development, but thanks to the Trust's founding members (as well as a kind bequest) the Valley was saved. The Trust’s first ever donation of land, Le Don Le Gallais, consisted of two blocks of woodland in the valley. This, along with a smaller area of woodland, was donated by Mr and Mrs Carlyle Le Gallais in 1937.
National Trust Land in the valley provides woodland habitat for a variety of captivating species. The dominant tree species in La Vallée des Vaux are Oak, Beech, Sycamore and Sweet Chestnut, although Ash and Wild Cherry are also present. Between the trees the ground is quite open, although patches of Bramble, Gorse, Bracken and Holly can be found, as well as Fly Agaric Mushrooms and Navelwort. Visitors may also chance upon the Red Squirrel, as well as numerous woodland birds such as the Great Spotted Woodpecker.