The Wood for the Trees: The Long View of Nature from a Small Wood. Richard Fortey

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СКАЧАТЬ as the distant recesses of the wood; it is rather an ineffably deep blue dotted with stars. As I look upwards the lamplight catches on horizontally disposed beech branches, making drapes of them, a series of stacked canopies fading upwards. Our sampling site has become a kind of theatre, with beech trunks making the proscenium columns, framed by swags of real leaves. Two small bats now flutter into the auditorium, briefly picked out by the illumination: in and out, and then again. Will they scoff the moths we have worked so hard to attract? When a Brimstone Moth (Opisthograptis luteolata) arrives even I, a moth beginner, can identify it, since apart from a few reddish splashes on the front of the wings it is all brilliant sulphur yellow. In contrast, the Waved Umber Moth (Menophra abruptaria), the size of a small leaf, is so perfectly disguised it looks like a fragment of animated tree bark; at rest during the day it is invisible. New arrivals continue. The light attracts a kind of living fuzz of many other tiny insects I cannot identify. They all have secret livings to be made in the wood, if only I could know what they were. Somewhere in the distance a screech owl cries, but not so fiercely, as if in sympathy.

      Andrew Padmore will return to the wood many times. More and more moth species will be attracted to his lure, which is later replaced by a solar-charged model hidden deep in the trees. No harm is done to the gentle moths: a photograph is taken and they are released to go about their business. As I write the list of species recovered has now climbed beyond 150. Different moths are on the wing at different seasons, finishing perhaps with the November Moth. There is a curious poetry about moth names, which is an esoteric language of analogy, allusion and colour. The wood has yielded more than half a dozen different species of carpet moths. There are several pugs and rustics, thorns and swifts, footmen and oak beauties. Who can resist the Chinese Character, the Coxcomb Prominent, or the Feathered Gothic? Or Bloomer’s Rivulet, the Rustic Shoulder Knot, Blood Vein and Mocha? They are all in the wood. Sometimes the common name is a simple description: the Blood Vein does indeed have a single, bloodily tinted vein describing a clear line like a gash across the middle of the wings. The Chinese Character does carry a distinctive pictogram; but it more closely resembles a bird-dropping when at rest. The Flounced Rustic is a furry, wonderfully complex, mottled and blotched mass of tans and greys; but I fail to see the flouncing. The Mocha is a nationally scarce buff-and-brown moth that maybe suggested coffee to some entomologist in the early days of the science. All the names have charm. Nobody could argue about the origin of Peach Blossom (Thyatira batis); it is marked as if some evolutionary leprechaun had implanted a few whole, pink flower heads on the darker forewings – just for fun.

      We caught some moth species only once; they probably included wanderers from grasslands and gardens, feeding on plants that are not found in the wood. I would have loved to find more hawk moths, but we don’t have poplars or convolvulus to nourish their caterpillars. The moths most commonly trapped are naturally those whose food plants are present in Lambridge Wood. They are an intrinsic part of the ecology. The incomparable Peach Blossom is a bramble feeder, our commonest shrub. The most abundant species of all was trapped 111 times: the Clouded Magpie (Abraxas sylvata), a large and very pretty white moth blotched with patches of orange-brown, grey and black. Its food plant is wych elm, and Grim’s Dyke Wood has plenty of wych elms. Andrew had never realised that it could be so numerous – but then, elms are not so widespread these days. The Gold Swift (Phymatopus hecta) is one of the few insects that can feed on bracken, that potpourri of pernicious poisons, and does not have far to fly to find its favoured larval foodstuff. The little brown Snout Moth (Hypena proboscidalis), all pointy at the front and the shape of a tiny delta-wing aeroplane, needs nothing more than nettles. Despite its name, the Willow Beauty (Peribatodes rhomboidaria) can feed on tough ivy. This moth is a wonderful confection of brown and black speckles on a buff background – the very embodiment of the word ‘cryptic’. It is so cryptically coloured the wonder is that the lepidopterists ever discovered it at all. The Satin Beauty (Deileptenia ribeata) is almost as well-disguised, and can feed on uncompromising yew needles. Then I must catalogue forty Lobster Moths (Stauropus fagi), dullish-coloured and almost as big as your thumb, and very plump and hirsute; as their Latin name implies they favour Fagus, and there are beech trees as far as the eye can see.

      The Lobster Moth reminds me of an interesting puzzle. In spite of the wealth of its lepidopteran life I have noticed very few caterpillars since I have owned the wood. I have to conclude that this ‘eating machine’ stage of the moth’s life takes special trouble not to be observed: a green body on green foliage, stick-like mimicry, rolling a leaf into a private self-service restaurant – these are some of the tricks of the larval trade that different species employ to avoid a questing beak. Only very poisonous species like to announce themselves in yellow and black stripes. On a hazel stick I did find the caterpillar of a member of the geometer family (it might even have been that of the Brimstone Moth), a typical ‘inchworm’ with legs only fore and aft along the body, so it progresses by looping up its midriff as it brings its hind legs forward. Measured steps are not an inaccurate description (hence the geometry). When it stops under the threat of my close eye it raises one end into the air and becomes a twig. Even more, it shows countershading. That is, its upper part is darker than its underside. Normally, things lit from above are relatively illumined on that side, which makes them more conspicuous. By introducing compensating darker tones on the dorsal part of the body such contrasts are flattened out: the object (well, inchworm) melts into the background. As they say on soap powder advertisements: it really works!

      As for the Lobster Moth, high in our beech canopy, it is a deceiver to dumbfound John le Carré. When the larva first hatches from the egg it is an ant imitator, with spindly legs that wave around a lot, and it thrashes about like an injured ant if it is disturbed. The young caterpillars are reported to defend their egg territory, and will drive off any rival caterpillar that comes too close. As they moult and grow they become both voracious leaf consumers and very odd looking – one of nature’s gargoyles. The head is larger and the legs behind it (the thoracic legs of the adult) become unnaturally attenuated even as the four pairs of legs further behind become stumpy and grasping. The back gets covered in humps, and the tail end can turn back on itself like some kind of turgid bladder, all finished off with a spike. The entire caterpillars develop a shade of pinky brown, and since they can be seventy millimetres long fully grown they are quite enough to give a shock to any casual stroller who comes across one; especially when their body is raised in the threat position with the head arched back. It is said to resemble a cooked lobster; it is certainly scary.

      I wonder if all of our 150 or so moths have such complex tales to tell. The beech canopy is humming with life stories, the brambles alive with deceptions and role-playing, each crack in the bark of every tree a dark dive hiding darker narratives.

      Beech

      By June, the beech canopy has garnered all the light, each leaf second-guessing its neighbour at grasping any space giving on to the sky. The taller trees soar upwards for more than a hundred feet. From the ground they seem all trunk, but from the sky they seem all crown. The beech (Fagus sylvatica) has always been a working tree: for furniture, fire and faggots. John Evelyn’s Sylva, the first book published by the Royal Society in 1664, and the founding text of forestry, said of beech trees: ‘they will grow to a stupendous procerity, though the soil be stony and very barren: Also upon the declivities, sides, and tops of high hills, and chalky mountains especially.’ Evelyn then quotes an old rhyme:

      Beech made their chests, their beds and the joyn’d-stools,

      Beech made the board, the platters, and the bowls.

      Three hundred years ago, beech may not have built the houses, but it did almost everything else. The management of beech trees has been the story of our wood for centuries.

      In 1748, Peter Kalm, a Finnish protégé of the great Swedish botanist Linnaeus (who named the beech tree scientifically), made an informed journey through the woodlands of England.1 He observed the Chiltern lands at Little Gaddesden, a short distance from our wood over the Buckinghamshire border. Some of the trees he СКАЧАТЬ