Gunnersbury Triangle is a 2.57 hectare Local Nature Reserve in the London boroughs of Ealing and Hounslow, immediately to the east of Gunnersbury. It became a reserve when, for the first time in Britain, a public inquiry in 1983 ruled that a planned development of the land could not go ahead because of its value for nature.
It has free admission and its entrance is on the south of Bollo Lane, a few yards from Chiswick Park Tube Station.
In the 19th century, the area is shown on maps as orchards and gravel quarries.
The triangular area now occupied by the reserve was delineated by three railway lines, two belonging to the District Line (now part of London Underground's sub-surface lines), and the now defunct London and South Western Railway (LSWR). There was once a bridge into the triangle from the west, and in the 1940s it was used as railway allotments (vegetable gardens), but when London Transport's Acton Works was built, the bridge was abandoned. The area, thus disused, was colonised naturally by grasses and trees in a "secondary succession".
In 1981, the site was proposed for commercial development, provoking an energetic campaign by the Chiswick Wildlife Group, formed in March 1982, which became the local branch of the London Wildlife Trust. The threat to the site was one of the first to be highlighted by the London Wildlife Trust on its formation in October 1981. The campaign led to a Public Inquiry in July 1983, which determined that the site should be devoted to nature conservation. This was the first time anywhere in the United Kingdom that a Public Inquiry had ruled in favour of nature in a city, and the Gunnersbury Triangle example became a test case.
According to the New Scientist, writing in 1985, "the celebrated Gunnersbury Triangle - an undisturbed piece of woodland surrounded by railways including the District Line .. was bought and preserved by Hounslow borough from British Rail with a GLC grant of £58 000.[note 1] The GLC also gave expert ecological advice when Hounslow council contested a public inquiry to save the Triangle."
The London Wildlife Trust has managed the Gunnersbury Triangle on behalf of the London Borough of Hounslow since 1985.
The London Borough of Hounslow formally designated the Gunnersbury Triangle as a Local Nature Reserve in 1987.
The London Borough of Ealing formally designated the part of the Gunnersbury Triangle that lies in Ealing as a Local Nature Reserve in 1991.
In 1993, recalling the dramatic events, the President of the London Natural History Society, David Bevan said:
- "On November 19th 1987,... The Gunnersbury Triangle was declared by Hounslow Council. The circumstances that led up to this important declaration are vividly described in David Goode's book. This was emphatically not a rural site. It was surrounded on all three sides by railway lines and had only been in existence for a mere forty years."
Bevan quoted Goode as saying "It had none of the features which, in traditional nature conservation terms, would make it a place worth preserving", going on to explain this remark as follows:
- "Nevertheless, the woodland that had grown up on it provided the only genuinely wild place for miles around and it was greatly cherished by local people. British Rail, who owned the site, had applied for planning permission to put up warehousing over the whole of the triangle. This was refused by Hounslow Council and a public inquiry followed in 1983. The Inspector ruled that the development should not be allowed because of the considerable local ecological value."
Gunnersbury Triangle is a classic "railway triangle", the 2.7 hectare space in between three curving railway lines. To the west is the Richmond branch of the London Overground; to the south, the District line; and to the northeast, the disused track of the London and South Western Railway (there remains the Piccadilly line a little further north, crossing Bollo lane). Much of the area is now wooded, consisting of the following habitat types:
- Birch woodland, in the drier places
- Wet Willow woodland, in the wet hollows
- Scrub, at woodland edges
- Acid grassland, with Sheep's fescue, hard fescue, Squirrel-tail fescue, Mouse-ear hawkweed, Cat's ear, and Yarrow.
- Pond, with
- Aquatic plants: Reedmace, Reed (Phragmites), Purple loosestrife, Water forget-me-not, Yellow iris, Common water-plantain, Figwort, Soft rush, Gypsywort, Common water starwort, Curled pondweed, Hornwort.
- Marginal plants: Floating sweet grass, Fool's watercress, Water mint, Brooklime.
- Problem species: Duckweed (Lemna), Water fern (Azolla).
Gunnersbury Triangle is a Local Nature Reserve and a Site of Metropolitan Importance for Nature Conservation.
Key: Compartments on map
- Compartment 1: Silver birch woodland succeeding to mixed deciduous woodland
- Sub compartment 1a Scattered, mature birch trees; rough grassland with tall coarse grasses, and low-growing acidic grassland
- Sub compartment 1b Bracken
- Compartment 2: Birch/Willow woodland, plus Phragmites stand and associated mounds
- Sub compartment 2a: Woodland Glade
- Sub compartment 2b: Common reed
- Sub compartment 2c: Rare ferns
- Sub compartment 2d: Mound
- Sub compartment 2e: New mound resulting from bridge removal
- Sub compartment 2f: Clearing south of former bridge
- Compartment 3: Willow woodland and associated wetlands
- Sub compartment 3a 'the Mangrove swamp'
- Sub compartment 3b Low-lying, wet area by pond with wetland herbs
- Sub compartment 3c Damp area by central ride
- Sub compartment 3d Coppiced willow woodland
- Sub compartment 3e Small area of wet birch and willow woodland
- Compartment 4: South-west facing bank and hedge
- Compartment 5: Acid grassland
- Compartment 6: Neutral grassland
- Sub compartment 6a: Large Meadow
- Sub compartment 6b: Small Meadow
- Compartment 7: Woodland/scrub in north corner
- Compartment 8: Pond
- Compartment 9: Ramp with tall herbaceous plants
- Compartment 10: Entrance yard
The Gunnersbury Triangle is regularly visited by school parties, which study grassland, woodland and pond ecology.
According to the TES (formerly the Times Educational Supplement), "From April, holly blue, peacock and brimstone butterflies abound. Following the illustrated guide, you wind among wild cherry and rowan, under archways of hazel branches to a pond where damsel-flies dance in early summer. A sparrow-hawk nests in a silver birch, a jay comes visiting, bees and wood-mice also live here."
The TES continues: "There are open glades for picnics and, in autumn, blackberries to gather. The aim here is to manage the woodland as a natural piece of countryside in town, and if, from time to time, you glimpse a tube train, you hardly notice it, beyond the trees."
The reserve is open to the public. The London Wildlife Trust runs guided visits such as Fungus Forays every year. On Open Days, staff and volunteers organise activities to enable children and adults to learn more about nature conservation in a relaxed environment.
From time to time, companies provide teams of volunteers to work for a day on tasks such as clearing scrub and repairing paths and fences.
The London Wildlife Trust's long-term management objective for the site is "to manage the nature reserve to conserve its natural biodiversity, and to conserve its matrix of woodland, wetland and grassland habitats through appropriate management", which includes coppicing, clearing scrub, mowing, and controlling invasion by non-native species, while "preserving the feeling of 'wilderness'".
The Mayor of London's Biodiversity Strategy comments "Over the last few decades, many exciting places have been established where city people are able to enjoy the natural world, often on sites which at the outset had seemingly little to offer. These include Camley Street Natural Park in King's Cross, Gillespie Park in Highbury, Gunnersbury Triangle in Chiswick, ..." and explains "The important message conveyed by these projects, regardless of their size, is that significant achievements for nature conservation are possible even in the most urban of settings, and often on modest budgets, provided there exists a cocktail of goodwill, optimism, commitment and professional back-up. Moreover such projects often yield social benefits, providing a community focus."
These photographs, all taken in the Gunnersbury Triangle nature reserve, illustrate some of its biodiversity.
Blusher mushroom, Amanita rubescens
Turkeytail bracket fungus, Trametes (Coriolus) versicolor
Candlesnuff or Stag's Horn fungus, Xylaria hypoxylon
Newt, Lissotriton vulgaris
Marble Galls of gall wasp Andricus kollari
Puffballs, Lycoperdon perlatum
Toad, Bufo bufo
Knotgrass moth caterpillar Acronicta rumicis
Click Beetle Athous haemorrhoidalis on Sallow
Aphids and live young on Sycamore
These photographs illustrate the educational and conservation activity on the reserve.
- Gunnersbury Triangle Summary Management Plan 2005-2010. London Wildlife Trust. June 2008.
- Goode, D. A Green Renaissance. In: Wild in London. Michael Joseph, London, 1986.
- Sands, Tim. Wildlife in Trust: a hundred years of nature conservation. The Wildlife Trusts, 2012. Pages 391–394.
- The land was far from 'undisturbed', being entirely a secondary succession. It was not only woodland but acid grassland and other habitats. It was only partly surrounded by railways. The 'GLC' was the Greater London Council.
- "Gunnersbury Triangle". Local Nature Reserves. Natural England. 18 December 2013. Retrieved 22 January 2014.
- "Map of Gunnersbury Triangle". Local Nature Reserves. Natural England. Retrieved 18 February 2014.
- Gunnersbury Triangle, London Wildlife Trust
- Geograph: Gunnersbury Triangle Nature Reserve. Alan Murray-Rust. 22 December 2010. Retrieved 17 January 2012.
- Gunnersbury Triangle Summary Management Plan 2005-2010. London Wildlife Trust. June 2008.
- Sands, 2012.
- Paul Simons. A city fit for wildlife. New Scientist. 28 March 1985. Pages 30-33.
- David Goode. Wild in London. 1986
- Bevan, David (1993). "The London Naturalist". Conserving Nature in London. London Natural History Society. pp. No. 72, 9–14. Retrieved 17 January 2012.
- "TES magazine". Inner-city sanctuaries. TES. 24 September 1999. Retrieved 17 January 2012.
- "EDF Energy". Historic woodland gets a helping hand thanks to EDF Energy volunteers. edfenergy.com. 27 July 2011. Retrieved 20 January 2012.
- "The Mayor's Biodiversity Strategy". Connecting with London's nature. Greater London Authority. July 2002. p. 79. Retrieved 2 February 2012.
- LWT: Gunnersbury Triangle
- Access Map and Reserve Information
- London Wildlife Trust
- ChiswickW4: Chiswick Wildlife Group & Gunnersbury Triangle
- Gunnersbury Triangle, VisitWoods website
- Geograph: Gunnersbury Triangle in the snow
- London Sound Survey: Dawn Chorus in May, Gunnersbury Triangle
- Rural London: North Side: Gunnersbury Triangle