Whitmoor Common comprises a series of heathland pockets that are surrounded by woodland, which vary in content from Scots pine stands and birch coppice to secondary oak and birch. The common is, together with neighbouring Rickford Common, the largest area of open heathland in the Guildford area and supports a vast range of species that are specific to heathland environments; as such they are important from a county perspective.

The common was once grazed by the commoners’ stock which helped maintain the open aspect that, in parts, can be seen today. Since the practical cessation of commoner’s rights and traditions, the common has increasingly become prone to afforestation by the natural invasion of Scots pine and silver birch. Heathland is surviving on the common and the preservation and expansion of this is one of the main priorities for the site. Whitmoor Common contains areas of wet and dry heath which have been encroached by woodlands of various mixes along with bracken and certain dense grasses. The predominant species are ling, cross-leaved heath and bell heather.

Around the wetter areas there is also a mix of heath and willow with an area of alder carr on the edge of the common. To the east and south of this point there are stands of aspen.
The large water body in the centre of the common is a major focus for dragonfly activity in the area, with 19 species being recorded in or around the vicinity of the pond itself. The stream running through the common also provides a habitat for the water vole, and with some management work this species should be able to colonise the pond.