The Wisdom of Trees

by Max Adams

  Maybe that was the way it happened; there are other possibilities. Trees, young trees, are bendy, some more than others. A young ash or rowan will not only bend all the way to the ground, but will stand up straight again when you let go; it’s part of trees’ defence against wind, a function of their tensile strength and the way their cells are stacked and connected. Most trees grow with a slight spiral twist like old-fashioned cough candy, which makes them stronger, less prone to shearing. If you bend a sapling over and let it go suddenly, it whips back—very nasty if you happen to be in the way. The catapult is surely a simple adaptation of this observation. The elasticity of young trees in the forest probably gave humans the idea of using them to snare small animals, and many such traps have been designed over the millennia. In one possible scenario the bow and arrow might have been an intellectual extension of the sprung trap.

  Now the arrow is a fine thing; it allows hunters to be sneaky and strike without being struck at. As it happens, it takes more time and skill to make a shaft that will fly true than it does to knap a flint into an arrowhead. But it is more interesting to consider what else one can do with a bow. In its raw state the bow releases stored energy, potential energy, in the arm of the hunter; transfers it to the tensile elasticity of the bow, and releases it suddenly. Handy, but not much more sophisticated than throwing a spear.

  For me, the inventor of the bow is not nearly so smart as the person who, fiddling with a loose string on a bow, came to wrap it around a stick, perhaps an arrow, with a twist. At that moment the wheel becomes possible—perhaps even inevitable—because the axle has been born and it constitutes a dramatic leap forward along the line of human creative potential. Many mortals at that point might go ‘uhuh’ and put the experiment down, not seeing its potential. All it needs is an inventive mind with a little time on its hands that sees the future in a moment of visionary clarity; or maybe just keeps playing until something interesting emerges—these are the two sorts of engineer, surely.

  The first axle, I am sure, must have been deployed in the manufacture of fire. Rub a stick between the hands to generate friction and you get very hot, blistered hands and a fire in maybe every twenty attempts. It’s a sort of rotary motion, but it doesn’t work effectively because the energy in rotating the stick is dissipated in the hands, and it is constrained by a very limited reciprocity—the small movement back and forth. But introduce the bow and it imparts to the stick vastly more energy. Wrap the bow string around your stick with a single flick of the wrist so that the stick is trapped in a turn of the string. Now, nestle the top of your stick in a hollowed-out stone or a cup of wood and hold that with one hand; place the other end on another piece of wood, made of softer wood than the stick; move the bow backwards and forwards in a sawing motion, and its string rotates the stick much, much faster than you could do it with your hands. It’s still reciprocal motion, but what a difference! Pretty soon the soft piece of wood—an engineer would call it the bearing—receives the majority of the energy and resists, creating heat... then smoke... and fire. Eureka.

  CORK

  The trunks of cork trees, red in their nakedness, stand out in striking contrast to the dark green of their permanent foliage against the deep blue of the summer skies of Spain and Portugal and the vivid green of the vineyards with which they form a symbiotic economic partnership.

  With that, humankind has advanced beyond the animals. And, I think, long before we get the point of cooking, we realized that fire could help us. Not at first, I imagine, as a means of keeping warm and fending off night-time predators, but as an advantage in the great hunting adventure. When humans, or their ancestors, came out onto the plains of East Africa they would have noticed that as the dry season got drier and the rainy season drew nearer, lightning sometimes started grass fires in the savannah. It’s the same in Australia and the American prairies: a fact of nature. When the rains do come, these blackened areas of earth respond quickly, because there is no ground-cover and because of the natural fertility released by the ash of last year’s growth. Shoots of lovely fresh grass appear almost immediately, closely followed by all the grazing animals in the neighbourhood. And after that, the hunters arrive—but it might be a long walk and they might be late for the party.

  And so I think that our first deployment of fire was as a means of creating hotspots for grazing animals: that way they come to the hunter, rather than the other way around. The invention of the fire-drill meant that humans could begin, for the first time, to think about modifying their environment.

  Terraforming Ascension Island

  Ascension Island lies isolated more than a thousand miles from the nearest land in the South Atlantic. It is less than a million years old, and when the first voyagers visited it, Ascension was a barren place with few plants and almost no trees. Georg Forster, a German naturalist who accompanied James Cook to the island aboard Resolution in 1775, believed it possible that the island could be transformed by importing plants. He hoped that trees would attract rainfall and prevent erosion, while shrubs and grasses could be used to create fertile soils. The British, having enterprisingly taken possession of the island and rated it a ‘stone frigate’ in the Napoleonic Wars, set about improving its potential for supporting life. A garden was laid out by Marines on the slopes of its mountain to grow vegetables and fruit for the garrison. But when Charles Darwin visited in 1836, his journal recorded that the place was still devoid of trees. His friend Joseph Hooker, visiting Ascension in 1843, found just one.

  It was Hooker who, in collaboration with the Royal Botanical Gardens at Kew and the Royal Navy, arranged for plants to be sent from London: three-hundred of them between 1847 and 1850, chosen for their hardiness and drought-resistance. By the 1870s some five-thousand plants had been imported. Today, Ascension is crowned with a forest that gives its peak the name Green Mountain: forty or so tree species, including banana, fig, juniper, coffee and Norfolk Island pines. The ecological downside is that, of Ascension’s very few endemic native plants more than half have now become extinct. Playing at being God has its risks. On the other hand, the island does at least now have a healthy ecosystem. Who can say if terraforming is right or wrong?

  The luthier

  I am in Stefan Sobell’s Northumberland workshop, surrounded by wood: stacks of dark, exotic, but impeccably sourced hardwood bundles, neatly labelled matching pairs for the backs of guitars, citterns, mandolins and the odd bouzouki; German spruce, slow-grown and close-grained, for soundboards; hard, dark brown wood of the wengé tree (Millettia laurentii) for the necks; special strips of multicoloured inlay for the decorative finish. Then there are wooden benches made of deal, oak cabinets, dozens of clamps, braces and jigs for holding parts while they are glued and set; scores, if not hundreds, of tools with razor-sharp steel edges and handles made of beech or hickory polished by decades of use. The smell is… well… woody.

  Stefan is putting a new nut on my Appalachian dulcimer. (Readers of a certain age will remember Joni Mitchell’s Blue album; she composed and played many of those songs on her dulcimer.) The old nut, made of ivory, has over many years worn down where the strings pass through its notches, so that the action is now too low and the strings buzz on the lower frets. With a practised swipe, using a small hammer and an offcut from some previous project, Stefan knocks the old nut out; it feels almost like having a tooth extracted, but, like a dentist, the luthier is unsentimental. Stefan trims and fits a new, bespoke part while I watch; I daren’t ask if this one is ivory too. Probably not.

  We fall to talking about the craft of instrument-making, of the acoustic properties of woods. After forty years of more or less perfecting the art, Stefan admits that there’s not a lot of science in his work: it is empirical engineering governed by touch and feel, ear and sensitivity—his and his clients’. So-and-so likes a ‘big’ sound with lots of bass; another musician likes something more ‘ringy’ with overtones. Some of his guitars work better in studio conditions; all of them sound fabulous live.
Every instrument is a compromise between strength (strings are always trying to pull their instrument to pieces) and resonance: too strong a build and the sound is killed; then it might as well be an electric guitar, he says, looking at me over the top of his glasses. Too weak and it will fly apart. We wonder if there is an analogy with the great cathedral builders, who could not calculate the forces needed to keep up their spires, vaults and columns but with each great monument tested the limits of materials and design in the name of faith (and the sponsor). We decide that there is. Guitars are the same: the luthier is riding the edge between possible and desirable all the time; and for that matter the same applied to the construction of bridges and of ever-bigger, ever-faster sailing ships until the fundamental material was superseded at the beginning of the nineteenth century. Occasionally it goes wrong; but sometimes Stefan hits the jackpot and a new technique, method or material is incorporated into whatever comes next. And that is the way it has always been with wood.

  Stefan, who took apart a bad guitar in the early 1970s, decided he could make a better one and never looked back, tells me that when he makes a new instrument it must be a little too stiff at first; that wood eventually learns its trade, so to speak, becoming more flexible, giving up those crucial mellow tones that speak of maturity and allow the musician maximum expression—almost like work-hardening metal. Stefan mentions the name of a famous brand of acoustic guitar whose factory-produced instruments sound perfect when new but become ‘flabby’ after they have been played in. When Stefan has finished a new instrument and it comes back from the lacquering and finishing process he plays it himself at home for a while, almost as though he were teaching it its trade, before allowing a prospective client to try it.

  We talk about the different woods used in instruments: stiff, thinly planed and moulded hardwood for the backs and sides; soft for the tops, which Stefan arches in his own distinct way to produce a powerful, rich trademark sound. What about larch or Scots pine for tops, I ask? Birch, even? We discuss their various properties from a woodsman’s point of view, and from those of a luthier: their consistency, the closeness of the grain, their flexibility—even their colour. Musicians are slaves not just to sound but to beauty. A great guitar must be a visual treat as well as having a sound to die for.

  Wood with good resonance always has a certain flexibility, which Stefan tests when he is choosing the materials for a new instrument or an experimental model. He also says that he can tell quite quickly whether a piece of wood has musical potential. He knocks it with his knuckles and listens for what he calls its characteristic ring. If he likes it, he might use it; if not, it doesn’t get to sit on his shelves and wait its turn. He travels many miles each year to source the right-sounding, right-looking, sustainably sourced wood. It must have some indefinable aesthetic quality—a natural property of the wood, which is hard to predict even within a batch, never mind a species. He has never heard of birch being used as a soundboard and suspects there’s a reason why. Maybe, I say, they don’t often get grown to a large enough size; or maybe it is because birch can be a bit fibrous. Drums have often been made from birch, producing a lovely bright ring; but the wood for drums is ply, peeled off the log like a veneer by a blade while the log rotates, more or less like sharpening a pencil. ‘I might see if I can find some,’ he says.

  HORNBEAM

  The understated hornbeam is a dense, beautiful hedging plant and a tree that does not readily form forests, although it can grow to more than sixty feet in height. Its ridged leaves are something like a cross between those of the beech and the elm.

  Meanwhile, my re-nutted and re-strung dulcimer comes off the workbench, and Stefan strums a few chords on it before declaring it fit for purpose and handing it over. ‘Sounds fine,’ he says. As indeed it does.

  TREE TALE

  The Hazel

  The hazel (Corylus avellana): barely a tree at all when compared to canopy giants like oak, beech and chestnut. The tallest British hazel, at Kentchurch in Herefordshire, is a mere twenty-six feet tall. Nevertheless the hazel is a key partner in our cultural evolution. Its nuts are highly nutritious, and the hunter-gatherers of the British Mesolithic era couldn’t get enough of them; since hazel needs open, light conditions to flower and produce its nuts, we infer that the Mesolithic was a period of open woodland.

  As a wood, hazel’s significance lies in its ability to self-coppice, regularly sending up new, straight, vigorous shoots from the base of the trunk so that sometimes it is hard to tell if it has been coppiced by humans or not. It is the tree that taught us woodland management. Hazel’s value as the go-to material of the woodsman lies in its pliability, the slender straightness of the rods which it produces on a seven- or eight-year cycle, and the ease with which those rods split and can be cut using no more than a sharp billhook. After cutting, fresh hazel shoots can grow five feet or a metre-and-a-half in the first year.

  HAZEL

  Hazel is the woodsman’s tree par excellence. From it we learn that strength may come in small packages; that flexibility is a strength in itself, and that self-renewal is the art of survival.

  No fewer than twenty-six woodland products were traditionally made from hazel, ranging from pea-sticks and divining rods to baskets, hurdles, withies for roofs, barrel hoops and hedging stakes, to charcoal and firewood. It is indispensible as part of a woodland economy, and archaeologists and architectural historians find it everywhere when they dig or poke their way through ancient buildings, rubbish heaps and wet ditches. In the last hundred years the area under coppice in Britain has fallen from half a million acres to less than a hundred-thousand. The hazel has been replaced by plastic. It is a pity.

  Splitting, or ‘riving’, hazel rods is an art in itself. I was taught the trick (I say taught: I have never mastered it) by the great Bill Hogarth, last of the Cumberland master-woodsmen, who inserted his billhook blade, as if it were a mere fruit-knife, into the cut end of a rod, then worked it down the centre grain, feeling for where the blade might run off. Once he had opened a good split and knew that the rod was sound, he worked the rift against a wedge of wood hammered into the ground and then almost literally pulled the rod apart. Once split, the rod is the essential component of one of those simple treasures of technological culture: the hurdle. To form a hurdle you need a half-trunk of oak or beech, slightly curved, which you lay flat side down on the ground. Into the top of the trunk you drill (with an old-fashioned brace and auger bit) two holes about three-quarters of an inch in diameter and perhaps three inches deep, six feet apart. Into these you place two unsplit three-foot hazel rods, whose exposed points you sharpen. Then you drill five other holes at one-foot intervals between these, and of a slightly smaller bore of around half an inch. Into these go five unsplit rods: these are the warp of your hazel loom. The split rods are now woven alternately between these rods and around the end rods. And here is the trick: to bend the split rods around the end poles requires a twist and a firm grip, so that the grain of the wood almost rolls around the pole, without splitting.

  Few other woods will take such treatment; even with hazel it is impossible to weave as tightly as one would like—there is some play in the structure—but here the ingenuity of the hurdler comes in: when the weaving is complete and the hurdle is removed from its jig, the curve in the hurdle springs out straight to create the tension required to keep it firm and rigid, but still flexible. Shepherds taking their flocks onto high summer pastures used to be able to carry ten of these woven panels on their backs in one go, linking them together with ties in a circle to create sixty feet of fencing: a portable fold. Hazel hurdles have been found intact inside old structures, where they were used as the panels for wattle-and-daub walls, having survived for more than a thousand years.

  The hazel may be small, but it is the champion of the woods: the most useful of all trees. The Anglo-Saxons believed it to be their own special tree of knowledge. From it we learn that strength may come in small packages; that flexibility is a strength in
itself, and that self-renewal is the art of survival.

  7

  The Wood Age

  Axe, adze and wedge—Summer—The first carpenters—Stonehenge decoded?—The Nobel Prize-winning woodworker—

  TREE TALE: THE BEECH

  All good men love an axe; and all Prime Ministers and literary prophets in their old age are discovered by the visitor using an axe in the garden.

  JOHN STEWART COLLIS

  Axe, adze and wedge

  BEFORE THE INVENTION of an effective saw some time during the Bronze Age (roughly 2500–1600 BC), wood was worked with axe and wedge; earlier saws were just the jaw bones of cattle, unless you could get your hands on a crocodile. The axe and the wedge are such fundamental implements that it is easy to forget the millennia of improvements that led to their perfection, not just as the weapons of woodsman and carpenter (not to mention warrior) but also as instruments of exploration, which could prise open the secrets of wood’s strength and flexibility. Even in the nineteenth century it was perfectly reasonable to process most parts of a tree using these two simple tools.

  Neolithic axes look like seriously hard work to use—although these things are relative. The arrival of bronze technology was literally a revolution, perhaps even more profound than the later introduction of iron and steel. A good sharp bronze axe could—and can—cut a tree down quite quickly, skilled sharpening and preservation of the edge being the key (as with all tools). It could also be used to de-bark and trim the large boughs and smaller branches, and to shape the trunk as required. Wedges were used generally to split a trunk lengthways along its natural grain, and in skilled hands a clean straight tree will divide into even boards, which can be finished with the axe. The adze—effectively an axe blade set at right angles like a hoe and swung towards the user (keeping legs splayed apart for safety)—was a relatively small but significant modification of the axe, much utilized by shipwrights to trim boards and planks. The great Viking longships were made using axes, adzes and little more; but the adze requires great skill and experience to wield it usefully.