The Common is divided in to a number of sub-sites, a brief description of their respective natural history is given below, together with an accompanying map.
Seven Islands Pond Area
As its name suggests, this area houses the largest and best known of the ponds on the Common. Seven Islands Pond was created by early 19th century gravel extraction, which was required for the growing number of roads. The pond is full of life including birds, frogs, toads and dragonflies. However by the mid-2000s the pond was in danger of drying out due to a build-up of silt. To remedy this, in 2008 the pond was drained the silt removed and the islands re-profiled. To the north of the pond lie significant parcels of acid grassland, a nationally important habitat type supporting notable assemblages of plants and animals.
Much of the remaining area of this sub-site was used for rubbish dumping during the mid 20th century. The areas both sides of Cedars Avenue were infilled in the 1940s, and the hill facing the pond was the site of a domestic dump in the 1950s and 60s. Both of these areas are now dominated by vegetation associated with waste ground and disturbance. There are also significant tracts of woodland and scrub mainly along Croydon Road and Commonside East.
One Island Pond Area
This once flat area was re-landscaped during the late-1970s and early-80s to create the hills surrounding One Island Pond. These hills now support neutral grassland with a range of wildflowers, which create an altogether different scene during the summer months than those encountered on the Seven Islands Pond Sub-Site.
The pond is a result of gravel extraction during the early 19th century, and is home to a variety of wildlife. Other habitats in this area include a small parcel of acid grassland and stands of woodland and scrub.
Mill House Area
The Ecology Centre on Windmill Road, serves as a base for the staff who manage the Common. Next door to the Ecology Centre is the Mill House pub, the car park of which holds the remnants of the old windmill that was once in use here. Behind these buildings are the old football pitches that are now managed as neutral grassland, but were used as a tipping site, being reinstated after the Second World War. Further up Windmill Road is the new Meadows residential development.
East of Windmill Road are areas of acid grassland, heathland, scrub and woodland which together provide an interesting mosaic of habitats. In 2007 a large scrape was dug and subsequently seeded with heather increasing the coverage of heathland on the Common.
As with some of the other sub-sites on the Common, this area’s topography has changed in recent years due to the tipping of inert waste, which forms the hills east of Watneys Road. Between these lies Bidder’s Pond, created in 1990 and named after George Parker Bidder, who was instrumental in saving the Common for future generations to enjoy. In the north-west region of this area lies Arthur’s Pond, believed to have been dug in the 17th century. Both ponds have an abundance of amphibians.
The main habitat on the area is neutral grassland on the hills interspersed with smaller parcels of acid grassland. The once grand line of elms lining Commonside East succumbed to Dutch Elm disease in the 1970s and has now reverted to elm scrub, which is nevertheless a valued habitat especially for the White-letter Hairstreak butterfly.
Mitcham Golf Club boasts an enviable array of settings amongst its 18 holes, and is managed in a way sympathetic to them and their wildlife occupants. Habitats here include acid grassland, seasonal ponds and ditches, and the largest areas of heathland and woodland on the Common. These support a host of plants and wildlife, some of which are rare.
The golf course has received much upheaval in its history such as turf removal and extensive re-designing, but is now an area where golfers and walkers can both get pleasure from what it has to offer.
This sub-site’s profile remains relatively unchanged, and consequently still supports a good example of extensive high quality acid grassland. The Gunsite is so named because during the Second World War it held anti-aircraft gun emplacements and temporary living accomodation. Although all physical evidence of the emplacements is long gone, a number of the plants found in the south-west corner are remnants of early gardening activites. Other than pedestrian commuters walking to the Tramstop, this area receives fewer visitors and yet it is one of the most interesting and diverse areas of the Common.
Up until 2009 the main habitats here were a small hay meadow, much amenity grassland, woodland planted in the early-1990s and two watercourses. During 2009 the Conservators undertook a consultation exercise to gauge public opinion on a project to enhance the nature conservation value of the Green, by extending the hay meadow and woodland, whilst at the same time continuing to provide areas for informal recreation. There were no objections to this proposal and so from 2010 the mowing regime on the some of the amenity grassland parcels was relaxed, thereby benefiting wildlife.
Mill Green is dissected by two waterways. One is the Beddington Effluent Carrier, which takes treated effluent from the sewage works to the River Wandle. The other is a ditch, which was once part of a branch of the River Wandle. Although the Carrier is concrete-sided with little wildlife value, the water quality of the treated effluent is much improved in recent years and regular monitoring has shown that it now supports a range of insects and fish. The ditch on the otherhand is chocked with aquatic vegetation and heavily shaded along much of its length and is in need of some fairly drastic remedial management.
The following surveys are available to download: