[ timbers ]

Through the long history of the human race, a very great variety of timbers have been used. This is a short catalogue of some of the important timbers, especially those that are particularly suited to various crafts and musical instrument making.

Trees grow from the outside. Every year the trunk becomes a little larger and the bark has to "stretch" to accommodate this. Otherwise the bark would spit open like a sausage in a frying pan. In a mature tree, the living tree is only about 50% of the total volume. The timber dies from the centre and shuts down, while new layers are added at the circumference. The useful timber is divided into two very different zones. The core is typically darker and drier, called the heartwood. Although effectively dead, this is the high quality material. The living vessels in the tree carry water on an "upline" to the leaves and sap on a "downline" to the growing layer just under the bark, called the cambium. This ring of wet, soft timber is called the sapwood.

There is one basic distinction between different timbers of the world. They are divided into two categories are known as "hardwoods" and "softwoods". This may not always be a very helpful distinction considering the huge variations within the family of hardwoods, but it is at least a starting point.

Hardwoods

These timbers are so-called, not because they are necessarily hard, but in order to distinguish them from the family of softwoods (see below). Hardwoods form the family of broad-leafed trees. These trees have evolved to take advantage of the sunlight during long summer days. Typically (and there are many exceptions!) broad-leafed trees are shaped like a huge umbrella - the perfect solar collector. The large area of leaf enables them to grow very quickly in periods of warm sunshine, but in wintertime when the days grow short, the leaves are often a liability for several reasons. Firstly, there is very great moisture-loss through the leaves. When the climate grows cold, water may turn to snow or ice so that it is no longer available to the trees. If the trees were to continue at the same rate of transpiration through the leaves, they could not survive this rate of water loss, and would die. Secondly, in periods of snow, the leaves would trap the snow on the branches. Eventually, this would lead to a huge increase of weight bearing down on the branches, causing serious damage to the tree. Finally, in temperate climates the autumn and winter are often periods of storms and high winds. You know what happens to an umbrella in high winds! As a result, most of the broad-leafed trees in temperate climates lose their leaves in autumn, the time sometimes known as "the fall". The hardwoods span a huge range of different qualities, and defy most generalisations. The lightest is balsa wood. The heaviest is possibly ironwood, or some similar variety of tropical hardwood. All British fruit trees also fall into this category.

Most of the hardwoods used for instrument making are tropical in origin. If you look at a globe, you will see that convection currents in the air round the equator cause two bands of rainfall running right round the planet, one on either side of the line of the equator. The pattern of rainfall and the stable length of the days suit these trees very well and many of these varieties grow to massive heights to reach the light many metres above the forest floor. Tropical hardwoods are often very dense in weight and astonishingly beautiful in colour, ranging from the rich mid-browns and even texture of mahogany to the jet-black heartwood of the ebony tree.

Ironwood - The densest

Balsa wood - The lightest

Special uses

Ash - Fraxinus

A few particularly tough timbers have a grain structure that is almost "woven". In other words, it is very interlocked in three dimensions. Timbers like this are used for shatterproof applications, like hammer handles and billiard queues.

Ebony - Diospyros

The only naturally black timber in the world. Only the heartwood is black and constitutes about 50% of the volume of the tree. The sapwood is much paler, sometimes brilliant orange or grey, depending on the geographical area where the tree comes from. This wood is ideal for fingerboards for violins and guitars becaus it is so hard, and also because it does not discolour with constant touching. Ebony is extremely dense and sinks like a stone in water.

Lime - Tilia

A soft, silky timber particularly good for carving. If you look at any particularly ornate gilded picture frame, there is a very good chance that if you scratch away the gold you will first find bole (a fine clay coating to seal the gesso), then gesso (a white base for gilding made from plaster and rabbit skin size) and finally lime wood.

Mahogany - Swietenia

A wonderful timber of fine even grain and regular red-brown colour that transformed furniture-making. The evenness and stability of wood from Central and South America allowed much greater precision, particularly in the carving of decorations and the cutting of joints in drawers. Cuban mahogany was especially prized by Georgian furniture makers because of its wild vivid grain and glorious colour. The red fades somewhat towards brown. Brazilian mahogany is medium density and very stable, and so is very suitable for guitar necks. There are many other varieties of mahogany from countries like Africa and the Phillipines.

Maple - Acer

A cousin of the sycamore tree, Canadian maples are probably the best known, and also give maple syrup. Maple is so hard, it is ideally suited to flooring, but has a discreet beauty and tremendous strength, so it is much loved my electric guitar makers. Some trees, for unclear genetic reasons grow in a wavy fashion, giving quilted maple - a glorious rippling flame pattern wonderful for solid-body guitars. A similar thing happens to sycamore, giving violin-makers their "fiddle-back" sycamore.

Oak - Quercus

A fairly dense, dark wood once found in huge forests all over England, like, for example, Sherwood Forest near Nottingham, the legendary haunt of Robin Hood. Most of these English forests were destroyed during Tudor times (around 1600) to build what was at the time the most powerful Naval Fleet in the world. Oak is particularly rich in Tannic acid, and has many uses besides construction, for example, for tanning leather and for providing barrels to mature many fine wines. A particular variety of oak found in Portugal, called the "cork oak" also gives us more culinary help by providing cork from its bark. The recent trend of using plastic corks is currently threatening this ancient industry.

Poplar - Populus

A fluffy, pale and rather unexceptional wood. However, it was ideally suited to the sound desired by harpsichord makers of the later, Northern European school, who often used it for the cases. It was then gessoed, painted and gilded.

Rosewood

There are a huge number of timbers known collectively as "rosewood" or "jacaranda" in South America. It is believed that the name came not because the trees are in any way related to roses, but because the first rosewood varieties to arrive in Europe had a sweet, perfumed scent somewhat reminiscent of roses. They span a number of different unrelated families, but the botanical family of true rosewoods is "Dalbergia", a few members of which are particularly useful to guitar-makers.

Rio Rosewood - Dalbergia nigra

Found exclusively in the Brazilian province of Bajia. The name "Rio" was given, not because of the area where the trees grow, but because Rio de Janeiro was the port of export. This is a particularly beautiful wood of rich, chocolate brown colour, shot through with blacks, browns and sometimes pinks. I find the combination of dark brown and pink to be one of the most beautiful grain patterns of all the timbers. There is no other timber of similar brown colour, so it was used for knife handles, precious inlays (like Tonbridge Ware) and, of course, guitar backs. It fades over the years to a deep brown. This rosewood is now an endangered species, and is listed on CITES. This means that all trade is highly restricted.

East Indian rosewood - Dalbergia.latifolia

This tree has been used as a good substitute for Brazilian timbers when these were becoming in short supply. Now, in their turn, the supply is becoming limited. This timber is an interesting purple-brown, with strong striped grain whose pattern is only clearly defined when you are quite near to the surface. Over some years, it fades to a warm mid-brown. It is a very popular choice for guitar backs and sides. Some trees have been plantation grown as a cash crop in Indonesia (Sonokeling rosewood). The plantations were established by Dutch settlers many years ago, but to date the quality of the Indonesian timber is usually rather poor and the colour appears faded.

Service (Wild pear) - Sorbus

A hard,compact wood of very fine grain. It takes a superb finish straight from the tool. The overwhelming choice of harpsichord makers for making jacks, (the vertically running rods that hold the quills to pluck the strings).

Willow - Salix

A fluffy white timber that loves the water. Used to make cricket bats and when pollarded, gives fine flexible stems called "withies" in Dorset, used to weave into baskets and lobster pots. I sometimes use willow for linings and blocks in my guitars, although several other timbers are equally suitable.

Softwoods

This is the family of coniferous trees. The leaves are typically long waxy needles and instead of fruits or berries, the conifers usually spread their seeds with the aid of cones, as the name would suggest. Yew trees also belong to this family, but have drifted a little in their characteristics, with rather flat needles and berries for fruits. The timber is usually pale in colour and stripy in appearance, caused by the alternation of faster spring and summer growth, followed by the hard, dark grain of the late autumn. While the hardwoods often look like huge umbrellas, the conifers typically look like giant flag-poles, presenting a tall, thin outline to the snow and winds. Softwoods have a comparatively simple structure without the specialisation of the hardwoods, but because they grow tall and straight, this often gives very uniform timber with extremely good structural properties that translate into very good weight:strength ratios. This happens to be one of the most desirable characteristics for engineers and luthiers. So, for example, the largest wooden aeroplane in the world is nicknamed "the spruce goose" because of the timber used in its construction. Spruce (Picea) is also highly prized by luthiers for exactly the same reasons. There are many similarities between the different families and in practice, although spruce is probably the first choice of luthiers for their soundboard material, the families of fir (Abies) and pine (Pinus) are also quite suitable. However, any old tree will not do - for the resonance required by soundboards it is important to find trees with very close growth rings. In other words, the trees grow very slowly, giving a greater proportion of dense, dark wood to the softer, paler grain. The place to find such trees is near the snow-line high up in the mountains. In Europe, wood for soundboards comes from mountain ranges like the Alps and the Jura in France. Having selected suitable trees, the sawing is also critical. It is most important to follow the natural fibres of the tree, so the very best quality tonewoods are first cleft with a wedge to allow the break to follow the fibres, then dressed flat and sawn into planks. Violin-makers do not need parallel planks, so violin soundboards are usually made from a matching pair of wedges that come naturally from cleaving the tree.

Bristlecone pine -Pinus longaeva and Pinus aristata

Of no practical use whatever to craftspeople, but makes the hall of fame by being one of the oldest living things on the planet. They hug the ground in poor soil areas and look like a half-dead tree stump, but live to astonishing age - the oldest known tree, called "Methuselah", was discovered in 1957 and can be found in the White Mountains of California. It is currently 4,724 years old! There is now a dendrochronology based on this pine using either living or dead wood samples that is continuous for nine thousand years.

The redwoods.

On the edge of the softwood family, lie the redwoods. Native to the pacific coast of North America, the redwoods are some of the most remarkable trees and possibly the most record-breaking trees on Earth! The family of Sequoias are best known as the tallest and most massive trees on the planet. They also live for many hundreds of years and can claim to be among the older living beings in the world. Most of these forests have now gone, much of it used to fuel the housing boom in the expansion of California at the beginning of the 20th century.

Sequoia sempervirens and Sequoiadendron gigantea

The first is the tallest living thing on the planet, the second, the most massive, growing to some 11 metres in diameter. These trees have some of the tightest grain you have ever seen, and a wonderful rich red in colour. Sequoia can be used for soundboards, but as well as my reluctance to destroy such remarkable trees for their timber, the material is too brittle to be very practical as a soundboard. Even a slight impact causes it to split explosively down the grain line.

Western Red Cedar - Thuja placata.

Not truly cedar, nor entirely red! Western Red Cedar is found well north, around the Canadian border, and was the timber favoured by the Native Americans to carve Totem poles. Unlike the version propagated by the westerns, Native Americans of the plains never carved totem poles! There is still a strong tradition of carving in Canada using this timber. It began to be used by luthiers for guitar soundboards around 1960 and has proved to have wonderful acoustic qualities. It suffers from being rather brittle, and as a result is less practical for Flamenco guitars.

Spruce - Picea

The species of Picea excelsior, Alpine spruce, has been highly prized in Europe by luthiers through the ages. The straight, silky grain and subtle beauty make it ideal for soundboards.

Yew wood - Taxus

In evolutionary terms, when yew was young it was a softwood, but then it drifted. It is still classified as a softwood, but it has unusual features. In place of the needles, the leaves have become rather flat. In place of the cones, yew trees have bright red berries. These berries are poisonous, and are probably the reason why yew trees are considered magical. You can often find them planted in graveyards to keep away evil spirits. It's a shame Buffy the Vampire Slayer never discovered this fact, as it would have made her life easier. Apart from its supernatural powers, yew trees have killed a lot of people in other ways. This is the only wood you can use to make Northern European longbows. English yews are genetically wild and curly in grain, which is not at all what you need for a longbow. So English bows were always made from imported continental Yew. Although not widely used by luthiers, yew is a magnificent timber, hard in texture and with attractive grain and brilliant white sapwood. This brown and white stripe was exploited by later lute-makers for multi-rib lute backs. It is also a very attractive substitute for mahogany in furniture, and avoids the use of tropical hardwoods.

More information on soundboard materials