Gunnersbury Triangle facts for kids

Quick facts for kids Gunnersbury Triangle
IUCN Category IV (Habitat/Species Management Area)
Location	Hounslow/Ealing
Nearest city	London, England
Governing body	London Wildlife Trust

Gunnersbury Triangle is a 2.57-hectare (6.4-acre) local nature reserve in the London boroughs of Ealing and Hounslow, immediately to the east of Gunnersbury. It was created in 1983 when, for the first time in Britain, a public inquiry ruled that a planned development of the land could not go ahead because of its value for nature. It opened as a nature reserve in 1985.

The area consists mainly of secondary birch woodland, with some locally uncommon willow carr or wet woodland and a small area of acid grassland along the track of the former Acton curve railway. The reserve supports a varied population of plants, birds, amphibians, insects and other wildlife. It is managed by the London Wildlife Trust.

The reserve is maintained by London Wildlife Trust staff with the help of volunteers, and is open to the public. There is a varied programme of activities including wildlife walks, fungus forays, open days and talks. The reserve is used regularly by school and community groups, and for team-building work days by corporate groups. Its entrance, with a wooden five-bar gate flanked by hedges, is on the south of Bollo Lane, a few yards from Chiswick Park Underground station.

History

Gunnersbury Triangle local nature reserve campaign, 1988, showing children by the pond

The area is shown on 19th-century 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 Railway (now the District line of London Underground), and one to 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. 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.

In 2016, the Triangle's volunteers won an RE:LEAF Acorn Award for their "particular contribution to promoting or conserving trees".

Reserve

The former badger signboard, 2012

The wet woodland 'Mangrove Swamp' with willows

Gunnersbury Triangle is a classic "railway triangle", the 2.57-hectare (6.4-acre) 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. It is a local nature reserve and a Site of Metropolitan Importance for Nature Conservation.

Habitats

The following compartments are identified in the reserve's management plan:

• Compartment 1: Secondary birch woodland

This covers most of the reserve. Silver birch is dominant, with a few crack willow, goat willow, some wild cherry and sycamore in the canopy. Shrubs include hawthorn, elder, holly, yew and rowan, with garden escapes like buddleia, Oregon grape, cotoneaster, privet. There are some saplings of pedunculate oak, mostly around the edge, and holm oak. The field layer is mainly thick bramble, with ivy in denser shade. Ferns include male fern, broad buckler fern and the less common lady fern.

• Compartment 2: Secondary willow woodland

Willow carr (locally uncommon wet woodland including the "mangrove swamp") with goat willow, grey willow, and some crack willow, with hybrids. The shrubs and field layer are similar to compartment 1; there is some honeysuckle and common horsetail, hemlock water dropwort, gypsywort, yellow flag, pendulous sedge.

• Compartment 3: Eastern bank and hedgerow

Rough grassland with false oat-grass, Yorkshire fog, yarrow, cat's ear, with bracken at the south end. There is an uneven hedge of hawthorn and buckthorn. The sunny south-west aspect encourages butterflies including holly blue, Essex skipper and small skipper.

• Compartment 4: North neutral meadow (anthill meadow)

Very uneven meadow with mounds formed by the yellow meadow ant Lasius flavus, fox earths, and spoil dumped during former gravel works. Grasses especially false oat-grass, Yorkshire fog; also cock's-foot, common bent and sheep's fescue. Herbs include common vetch, meadow vetchling, white clover, yarrow, ribwort plantain.

• Compartment 5: North acid meadow (railway track acid grassland)

On the former Acton curve railway, with a substratum of gritty sand and ballast (hard acidic rock). Small fine grasses especially sheep's fescue, with fine-leaved sheep's fescue, hard fescue, squirrel-tail fescue, early hair-grass. Herbs include sheep's sorrel, mouse-eared hawkweed, cat's ear and yarrow.

• Compartment 6: Southwest meadow (picnic meadow)

Coarse grasses such as cocksfoot, Yorkshire fog, false oat-grass, annual meadow-grass. Broom has colonised on the site of an accidental fire.

Pond dippers on Frog Day

• Compartment 7: Main pond

Main pond, dug in 1986, with seasonally fluctuating water levels. Most vegetation has colonised naturally, with among others common reed, purple loosestrife, yellow iris, water-plantain, water figwort, soft rush, gypsywort, water starwort, curled pondweed, common duckweed, water forget-me-not, water mint, brooklime.

Six frogs spawning in the main pond

• Compartment 8: Small pond

Seasonal pond with water plantain, celery-leaved crowfoot, bittersweet, water figwort, and introduced yellow iris.

• Compartment 9: Tall herb meadow (beside ramp path from entrance)

Small meadow of tall ruderal herbs, changing with natural succession, held back by cutting, with plants such as cow parsley, hogweed, stinging nettle, false oat-grass, garden escape daffodils and irises.

• Compartment 10: Gardens

Entrance yard gardens sown with wild flowers; hedge mustard, hoary mustard and other ruderal species invading; hedges with native trees and shrubs; hops scramble up the hedges.

• Compartment 11: Infrastructure

Hut, sheds.

Usage

A painter at work on the boardwalk over the pond

The Gunnersbury Triangle is regularly visited by school parties, totalling some 1500 students per year, mainly in the summer when they can work outside. They 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 and wildlife walks 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.

Bumblebee in Gunnersbury Triangle's wildflower demonstration meadow planted with cornflowers and poppies

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'".

Value

The Mayor of London's 2002 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."

Biodiversity

These photographs, all taken in the Gunnersbury Triangle nature reserve, illustrate a little of its biodiversity.

Biodiversity

Vertebrates Fox, Vulpes vulpes Bank vole, Myodes glareolus, in capture-release population study Bank vole eating mugwort seeds (Artemisia vulgaris) Wood mouse, Apodemus sylvaticus Grey squirrel, Sciurus carolinensis, with sycamore fruits Toad, Bufo bufo Toads in amplexus with strings of toadspawn Common frogs, Rana temporaria, wintering under a habitat mat Smooth newt, Lissotriton vulgaris Sparrowhawk, Accipiter nisus Grey wagtail, Motacilla cinerea, Blackcap, Sylvia atricapilla singing An adult and a young slowworm, Anguis fragilis Butterflies and moths Peacock butterfly, Aglais io Red admiral, Vanessa atalanta Painted lady, Vanessa cardui Small skipper, Thymelicus sylvestris, on Yorkshire fog in anthill meadow Essex skipper, Thymelicus lineola, on north bank Large skipper, Ochlodes venatus, in ramp meadow Gatekeeper butterfly, Pyronia tithonus Holly blue, Celastrina argiolus, on ragwort Urban green-veined white, Pieris napi, on Buddleia Small copper, Lycaena phlaeas Comma, Polygonia c-album, on ragwort, showing white 'comma' mark Ringlet, Aphantopus hyperantus Knotgrass moth caterpillar, Acronicta rumicis Gypsy moth caterpillar, Lymantria dispar dispar, on birch trunk Gypsy moth male Early grey moth, Xylocampa areola Buff-tip moth caterpillar, Phalera bucephala, 70 mm long Silver Y moth, Autographa gamma, hiding on a log Cinnabar moth, Tyria jacobaeae, in small meadow Cinnabar moth caterpillars on ragwort on north bank Small china-mark moth, Cataclysta lemnata, always found near water Common white wave moth, Cabera pusaria Box tree moth, Cydalima perspectalis Herald moth, Scoliopteryx libatrix, warming up on a cold day by whirring its wings Jersey tiger moth, Euplagia quadripunctaria Ruby tiger caterpillar, Phragmatobia fuliginosa Pupae of parasitoidal wasps (Braconidae) on broad-bordered yellow underwing moth caterpillar (Noctua fimbriata) Dragonflies and damselflies Female black-tailed skimmer dragonfly, Orthetrum cancellatum Southern hawker dragonfly, Aeshna cyanea Large red damselflies, Pyrrhosoma nymphula, in wheel on yellow iris Bluetail damselfly, Ischnura elegans, on Yorkshire fog Male common darter, Sympetrum striolatum Immature female common darter Azure damselfly, Coenagrion puella Pair of azure damselflies, Coenagrion puella, in cop Willow emerald or spreadwing damselfly, Chalcolestes viridis, a recent arrival Pond life Dragonfly nymph, beetle larva (right), damselfly nymphs, water fleas in a pond dipping tray Leech Water scorpion Caddisfly egg mass on leaf away from the pond Great ramshorn snail crawling on muddy bottom Other arthropods Marble galls of gall wasp, Andricus kollari Stag beetle, Lucanus cervus, on deadhedge Click beetle, Athous haemorrhoidalis, on sallow Rose chafer beetles, Cetonia aurata, on hogweed, Heracleum sphondylium Devil's coach horse beetle (Staphylinidae) Carabid ground beetle, Pterostichus cf. madidus Aphids and live young on sycamore Field grasshopper, Chorthippus brunneus, in ramp meadow Meadow grasshopper, Chorthippus parallelus, in anthill meadow Speckled bush cricket, Leptophyes punctatissima , in picnic meadow Ichneumon wasp, Gasteruption jaculator, nectaring on hogweed Macrophya sawflies (Symphyta) mating on hogweed Male hairy-footed flower bee, Anthophora plumipes Female ivy bee, Colletes hederae, by her nest burrow Common carder bee, Bombus pascuorum on loggery Tree bumblebee, Bombus hypnorum nest in fallen willow tree Male long hoverfly, Sphaerophoria scripta Hoverfly Eristalis horticola Hoverfly on catsear Hoverfly Leucozona lucorum Rutpela (Strangalia) maculata, a longhorn beetle and a wasp mimic Woodlice sheltering in a nestbox Spiders Anyphaena numida, a North African spider, only the second UK record for the species Linyphia triangularis sheetweb spider female and male False widow spider, Steatoda sp., from a nestbox Basidiomycete<!--OLD_RED_LINK Basidiomycete OLD_RED_LINK-- Blusher mushroom, Amanita rubescens Fly agaric, Amanita muscaria Webcaps, Cortinarius Honey fungus, Armillaria mellea Mild milkcap, Lactarius subdulcis Purple swamp brittlegill, Russula nitida Rhodocybe gemina, a new species for the reserve Lilac fibrecap, Inocybe geophylla var. lilacina Peeling oysterling or soft slipper, Crepidotus mollis, showing internal gelatinous layer when stretched Flat oysterling, Crepidotus cf applanatus Sulphur tuft, Hypholoma fasciculare, on birch loggery Pale brittlestem, Psathyrella candolleana, on willow loggery Giant funnel, Leucopaxillus giganteus Clouded funnel, Clitocybe nebularis, large specimen Wood blewit, Lepista nuda Common cavalier, Melanoleuca polioleuca Lepiota cf. hystrix Rosy bonnet, Mycena rosea Twig parachute, Marasmiellus ramealis Waxcap fungus, Hygrocybe, cf H. cantharellus Sulphur Knight, Tricholoma sulphureum Coconut-scented milkcap, Lactarius glyciosmus Tawny funnel, Lepista inversa Charcoal burner, Russula cyanoxantha Ashen knight, Tricholoma virgatum Oyster mushrooms, Pleurotus ostreatus var columbinus in winter Puffballs, Lycoperdon perlatum Collared earthstar, Geastrum triplex Tripe fungus, Auricularia mesenterica Pestle puffball Handkea (Calvatia) excipuliformis Brain jelly Tremella sp. Pointed club, Clavaria acuta Golden spindles, Clavulinopsis fusiformis Dotted stem bolete, Neoboletus luridiformis (formerly Boletus erythropus), blue-staining when freshly cut Brown birch bolete, Leccinum scabrum Turkeytail bracket fungus, Trametes (Coriolus) versicolor Lyophyllum ulmarium on ivy-clad elder Birch Polypore, Fomitopsis betulina, on birch log Blushing bracket, Daedaleopsis confragosa Hairy bracket, Trametes hirsuta, on birch log Ascomycete<!--OLD_REDIRECT_LINK Ascomycete OLD_REDIRECT_LINK-- Birch woodwart Hypoxylon multiforme Oak pin, Cudoniella acicularis Candlesnuff or stag's horn fungus, Xylaria hypoxylon Dead man's fingers, Xylaria polymorpha Orange peel fungus, Aleuria aurantia Scarlet elf cup fungus, Sarcoscypha austriaca Eyelash fungus, Scutellinia scutellata Layered cup, Peziza varia Tan ear, Otidea alutacea Tar-Spot fungus, Rhytisma acerinum on sycamore leaf Dog's vomit slime mould, Fuligo septica 'Lower' plants Common smoothcap moss, Atrichum undulatum Flowering plants White dead-nettle, Lamium album Green alkanet, Pentaglottis sempervirens Male thick-kneed flower beetle, Oedemera nobilis, on catsear, Hypochaeris radicata flowerhead Spanish bluebells, Hyacinthoides hispanica Yellow iris or flag, Iris pseudacorus Spring show of forget-me-nots, Myosotis arvensis Celery-leaved buttercup, Ranunculus sceleratus, in the 'mangrove swamp' Alexanders, Smyrnium olusatrum, growing by a seasonal pond Evening primroses (Oenothera) in bloom on the entrance ramp meadow Scarlet pimpernel, Anagallis arvensis, on bare ground disturbed by hedge-laying Purple loosestrife, Lythrum salicaria Ragwort, Jacobaea vulgaris, in a clearing made by a fallen birch tree Rosebay willowherb, Chamaenerion angustifolium, in the anthill meadow Teasel flowerhead, Dipsacus fullonum Dog rose, Rosa canina Redcurrant, Ribes rubrum, from the railwaymen's gardens that were once here Broom, Cytisus scoparius hybrid, naturalised Red campion, Silene dioica, on ramp meadow Elder, Sambucus nigra, in flower as an undershrub Dogwood, Cornus sanguinea, in flower in the front hedge Hemlock water dropwort, Oenanthe crocata in wet woodland Mallow, Malva sylvestris, by ramp meadow Bindweed, Convolvulus arvensis, by ramp meadow Narrow-Leaved hawksbeard, Crepis tectorum, beside old railway track Bittersweet, Solanum dulcamara, on mound Weld or dyer's rocket, Reseda luteola, on disturbed bank Horseradish, Armoracia rusticana on ramp meadow

Activities

These photographs illustrate some of the educational and conservation activity on the reserve.

Activity photographs

The welcome blackboard Making birdboxes Painting butterflies Demonstration beehive with numbered queen bee Collaborating on a bird canvas Pond dipping Making a 'stained glass window' flower Looking at a dragonfly nymph on Frog Day Cutting the cake to celebrate 30 years since site was saved Volunteers clearing the picnic meadow Shovelling woodchips into sacks ...and loading the sacks into the LWT Land-Rover Using a circular saw to prepare an information panel Checking nestboxes for spiders before cleaning and repairs Repaired nestboxes for blue and great tits, unrepaired box at centre Putting up a nestbox Fixing a wooden railing to protect native ferns Scything the Anthill Meadow Photographing a freshly-emerged peacock butterfly in spring Inspecting the moth trap Identifying a pug moth Corporate involvement: a group from Mace digging an extension to the main pond Instructing a Headstart group Volunteers cutting reeds and desilting the pond Weaving a hurdle deadhedge A corporate group digging out wet woodland (willow carr) Muddy volunteer after a morning's work in wet woodland Wheelbarrow and tools after a morning's work in wet woodland Mycologist Alick Henrici leading a Fungus Foray De-brambling the butterfly bank Cutting a fallen birch after heavy rain Planting a hazel hedge Sieving earth for demonstration meadow Sawing a board to length for a boardwalk School visit in springtime Education officer asks a question Carrying a birch log for path edging Teaching Landscape Design course students Hammering in a post ... up Hammering in a post ... down Card cutout ladybirds for children's nature trail Ladybird masks London Wildlife Trust staff with everything you need for pond dipping Keeping path edges clear of ivy Entomologists on the hunt Entomologists beating oak leaves for arthropods Entomologists examining their catch Smooth newt, one of a series of painted wooden animals on a children's nature trail Clive Leeke teaching a hedge laying course A young entomologist at work on Bugs Day Rupa Huq MP with volunteers and London Wildlife Trust volunteer officer Netty Ribeaux Photographing a fly agaric on a Fungus Foray Unloading logs from the London Wildlife Trust Land-Rover for minibeast logpile Digging out wet woodland Painted wooden birds' eggs for an Easter nature trail Wooden leaves for a summer nature trail Staff and volunteers smoothing surface of mud sofa, a temporary barrier of local material Ivy leaf decoration for mud sofa LWT ecologist Tony Wileman on a transect survey of the plants in the anthill meadow Replacing a post in anthill meadow fence Volunteers cutting brash from a willow tree, felled across a path and bench by Storm Ciara