Willowmead is a small area of wet alder carr woodland, situated adjacent to the River Mimram, to the rear of the Willowmead housing estate at the western end of Hertford. Many of the alder trees are of considerable age and are multi-stemmed, evidence of past management. Other canopy trees include crack willow, ash and aspen. The shrub layer contains much osier as well as grey and almond willow, spindle, black and red currant, guelder rose, dog rose and hawthorn. The ground flora is rich in marsh and swamp species with tussock sedge frequent. Several small ponds have been created within the reserve in the last few years by volunteers, and these have been colonised by frogs and also dragonflies.
Otter and water vole have been recorded along the river. A reasonable selection of common birds is present, reflecting both the woodland and wetland elements of the reserve, including kingfisher and wintering siskin. Lesser-spotted woodpecker, spotted flycatcher, song thrush, nuthatch and treecreeper breed in the woodland, whilst mandarin, mallard, tufted duck, moorhen and coot breed along the river and its edge.
