Wood is what trees are made of, or at least part it. The main part. The part between the roots and the leaves. The inner part.
Wood is basically cellulose fibres, held together with lignin. The fibres are mostly a water transport system, upwards, between the roots and the leaves. Lignin is the glue that holds it all together and makes a structure out of the system. There are other types of fibres in trees, but the essence, the core, those that make up the substantial part are called xylem. They are on the inside and are the heart of this matter. Cellulose is an organic compound. That means it has carbon in it. It is a structural polysaccharide, which is why it can hold up a tree.
Micro-organisms like fungi and bacteria, under the right conditions of adequate moisture and oxygen, digest wood. They consume it. They convert the cellulose (and lignin, to a lesser extent) into a form that sustains them. Unfortunately for us, when this happens, the wood effectively disappears. It turns rotten and is soon gone. Sometimes, and maybe even most of the time, this is a good thing. Our forests are renewed.
When wood is dry enough, or hot enough, it can burn. Combust. This chemical reaction yields heat, flame and smoke (and ash), and also causes the wood to disappear. The heat can be very useful, to warm us and our food. Heat has been the principal use to which wood has been put for millennia. It is not the most efficient source of light, but will do when there are no better alternatives. The smoke is mostly just a problem. Unintended combustion is also unwelcome but it is part of the story of wood.
Wood has been a very useful material. It has been adequately workable with primitive tools to provide the earlier form of us with shelter and tools. The shelters range from the very rudimentary and expedient to, much more recently, tall buildings. Such tools as spears and arrows have been supplanted by all manner of other things, such as violins and crutches.
Those of us who work with wood have had an evolving set of descriptions. An early one would be woodcutter. This is the description I was given by my six-year-old daughter in her school report. It has the virtue of being easy to understand. It has usually been applied to the harvesting end of the work, but could easily describe a type of artist as well. A contemporary wood harvester might prefer to be called a lumberjack or now, more specifically a feller, skidder, sawyer and so on.
Our wood harvest now initially consists of gathering up logs, the shorn structure of the tree, the trunk. The logs are transformed into lumber at sawmills. Or they are pulped. Those are the principal outcomes of the forest-product sector, along with the ancillary chipping and reducing to fibres to support the fabrication of panel products.
The large aggregates of trees are usually called forests. Canada’s boreal forest is considered to be the largest intact forest on earth. Sometimes we can’t see the forest for the trees. This might be in anticipation of the usefulness of their constituents as wood. We even sometimes use the term wood interchangeably with forest. Woodlands. A walk in the woods. We know what trees are ultimately good for.
Once the wood is no longer an intact part of a tree, but not reduced to chips or pulp, we can put it to many uses. There is a large industry devoted to these purposes: the wood industry. The largest portion of our wood industry is concerned with buildings and furniture. Wood is readily adapted to making structures such as buildings. Although the structural wooden components are usually not visible, we seem to like the appearance of wood. So we use it for our interior furnishings and fixtures.
We also use it to make music with, to make art with, to make play with (skateboards for instance) although we use it for some of those purposes less than we used to. As examples, our skis are now composites, as our most of our boats.
But this may change. Fossil oil and its by-products are a diminishing resource as we all know. But bio-resins made from wood are being developed to take their place. If fungi can turn cellulose into fuel, so can we. Carbon fibre can be produced from lignin. There is a lot more to come.
Paul Epp is professor at OCAD University and chair of its Industrial Design Department.