The Structure and Properties of Wood as a Living Material
As a structural material, wood is matchless in its combination of properties, being not only light, stiff, strong, and tough, but also easy to shape. It is also beautiful and has the advantage of being carbon positive, storing carbon that it sequestered during the life of the tree. However, it also has disadvantages, being weak across the grain, prone to splitting and tricky to join. It is also apt to rot if subjected to periodic bouts of wetting. Wood owes all of these properties to its function in trees: to transport water up to its leaves; and to hold them up against gravity and the force of the wind. This webinar describes the structure of wood; it explains how it is adapted to its hydraulic and mechanical functions; and it shows how these adaptations give wood its unique structure and properties. It goes on to examine how humans started to exploit wood, developing tools that allowed us to harvest, split, carve and saw it. In particular, we will see how the invention of metallurgy transformed the craft of carpentry and human history. But of course, not all wood is the same. The webinar also describes how and why the wood from trees, with contrasting ancestry and ecology, differ so much in their structure and properties. From the light to the dense, from the pale to the dark, and from the plain to the highly figured and how in turn this affects the suitability of particular wood types to particular uses.
About the Speaker
Roland Ennos is visiting professor of Biological Sciences at the University of Hull. He has spent his career researching and teaching the engineering of plants and animals, from insect wings to birds’ feathers, to human fingerprints and fingernails.
Most recently he has concentrated on the largest organisms on earth: trees. He has investigated how their roots anchor them in the ground; how their leaves provide air conditioning for cities; how trees branch; and how their wooden skeletons transport water to their leaves and resists the huge forces applied to them by gravity and the wind. He summarised what we know about the biology and ecology of trees and forests in his book Trees, published by the Natural History Museum. He has also become interested in our crucial relationship with wood, which started even before our ancestors came down from the treetops and continues to the present day. He has reinterpreted the human story from this wood-centred point of view in his recent book The Wood Age. This shows how our evolution, how the development of civilisation, and how even the course of modern history have all been shaped by our relationship with this most versatile material.