The Wood Age How Wood Shaped the Whole of Human History

Throughout human history, wood has been our constant, if somewhat overlooked companion. With The Wood Age, professor of biological sciences Roland Ennos delivers an eye-opening piece of environmental history. Reaching beyond the boundaries of this discipline, it gives the reader a comprehensive picture of how we have shaped wood and how, in turn, wood has shaped us.

The core of The Wood Age is an environmental history as you might expect it, charting our use of wood through time, though it is driven by an interesting and, to me, novel argument: "technological advances in other materials helped people make far better use of the material they had always exploited: wood" (p. 78). In Tree Story, Trouet made a similar argument, writing that "human civilization as we know it is founded on trees" (p. 201). Ennos argues that the importance of stone tools has long been overemphasized. Many of them were probably accessories to create better wooden tools. It is an attractive idea, though somewhat tenuous given wood's tendency to not be conserved in the archaeological record. With later technological progress, however, this argument starts to look more and more convincing.

Take later stone axes with blunt heads made from jade or basalt. Although seemingly useless for chopping wood, they were excellent at splitting it. Metallurgy gave us better weapons but also better woodworking tools. The refining of copper coincided with the production of the first plank ships and wheels. Iron allowed us to make the first saws, planes, and lathes. Other advances were the switch from working with freshly cut wood, so-called green woodworking, to using wood that has been allowed to dry out, or the steaming of wood to bend it. Wood allowed us to overcome the limitations inherent in large stone structures – Ennos even writes that "the history of architecture can be seen as the development of increasingly effective techniques to harness timber to stabilize and shelter ostensibly stone buildings" (p. 156). We shaped wood ever more precisely, making everything from furniture and household items to beautiful musical instruments.

Even the Industrial Revolution did not spell the end of wood. Wrought iron allowed metal joints to be incorporated into larger wooden structures, while the invention of industrial machines gave us mass-produced nails and screws, making everyone a carpenter. Wood pulp fed a booming newspaper and book industry and we engineered wood into new materials such as plywood, chipboard, cardboard, and, more recently, laminated wood (glulam) and crossed-fibre laminates that are used to make the enormous beams seen in wooden high-rise buildings.

For all its miraculous properties, an interesting argument that Ennos develops here is that wood also locked us in a period of technological stasis. The Romans already hit upon the limits of what could be achieved with wood, with e.g. ships and roof trusses not increasing in size with time. Given the poor state of roads, transporting wood over any appreciable distance was expensive. Only port cities or those along navigable rivers could easily float wood in from further away. This also meant that many fuel-intensive industries that produced e.g. glass or iron were scattered throughout forests, close to their fuel source. There was a literal disconnect between craftspeople and the burgeoning class of scholars at universities and little exchange of knowledge. Though craft guilds also had a role to play in stifling innovation. It was not until some countries hit upon fossil fuels that this technological deadlock was broken.

Ennos has previously written about both trees and biomechanics. His background knowledge has seeped into this book as he delves into a fair bit of materials science, metallurgy, architecture, and woodworking. Though his explanations are clear, the only minor complaint I had was the use of unfamiliar terminology. The plates section offers some illustrations, but I still found myself looking up certain woodworking joints, architectural terms, or tools.

This point aside, what elevates this book beyond "merely" a solid piece of environmental history are the chapters that bookend the core. The first three chapters are an unexpected dive into primatology, showing our deep affinity with trees. It is pretty well known that various great ape species fashion tools out of sticks, but fewer people might be familiar with the treetop nests in which they sleep. Furthermore, Ennos considers the evolution of bipedalism. Might it have evolved in the treetops when walking along branches? This was one of several ideas discussed, though not favoured by, Begun in The Real Planet of the Apes. And he briefly touches on the limb anatomy of Ardipithecus ramidus (especially its big toe, such a bone of contention in Fossil Men).

At the other end, the penultimate chapter takes aim at what Ennos calls deforestation myths. A superficial reading suggests he is contradicting himself as he next outlines how much impact we have had. However, what he takes issue with is the narrative told by the likes of Jared Diamond that deforestation led to environmental catastrophe and eventual civilizational collapse. The idea that felling trees results in catastrophic soil erosion is based on modern industrial forestry practices, he claims, "our impressions exaggerate the historical extent of the problem" (p. 246). Ennos in no way suggests that deforestation itself is somehow a myth: "environmental historians are starting to realize that even before industrial times our impact was enormous" (p. 258). "Virgin" rainforest has long been under cultivation and there is a clearly documented decrease in both forest cover and species diversity with time, with practices such as plantation forestry adding further insult to injury by introducing plant pests and diseases. Indeed, writes Ennos, the only times when forest cover rebounded in Europe and the Americas was after major events such as the fall of the Roman Empire or pandemics.

Looking ahead, high-tech uses of wood have the potential to replace steel and concrete though I appreciated Ennos's scepticism. Such wood products are energy-consuming to fabricate, while technofixes "continue to move our juggernaut economy even further along the path of unlimited economic growth" (p. 272). Instead, he has several suggestions by which we could make trees part of our lives again and so undo the disconnect that has grown between people and forests.

The Wood Age is an eye-opening piece of environmental history that considers a wide range of topics and is particularly strong on the materials science aspect of wood. It joins a recent crop of excellent books on trees and forests and, if you enjoyed any of these, comes highly recommended.