A walk in the woods - to look for guitars? No, I didn’t leave my guitar in the woods by mistake on a camping trip.
Actually, I was looking for trees that are suitable to make wood parts for guitars, called tonewood.
I recently visited with a NH business owner who specializes in exactly this. He has been involved with music, sound, and wood for his entire adult life. He has built guitars, owned a company that made loudspeakers with wood cabinets, supplied specialty wood for famous rock guitarists’ signature lines of electric guitars, and has been involved in producing tonewood for many years. He described tonewood production as being more akin to gem cutting than lumber production.
So what is tonewood? It’s the wood used for the tops, sides, backs and necks of guitars, violins, mandolins, and other stringed instruments. The producer I visited, specializes in tonewood for guitars. The top of the guitar, the soundboard beneath the strings on the main body of the instrument, is usually made of spruce. Various spruce species are used, but red spruce, a New England native, is described as a “holy grail” of tonewoods. The properties of red spruce wood produce excellent acoustic results. There is a lot of science behind what makes certain woods suitable for musical instruments, but there is a lot of art in recognizing and optimizing it. An experienced tonewood producer can knock on standing trees with a hammer or his hand and get a sense of whether or not they will yield good tone wood.
Not just any red spruce is suitable to become a guitar top. The tree needs to be at least 24” in diameter at breast height (preferably 28”), and the minimum top diameter of a log is 20”. The wood can have no more than 8 growth rings per inch, with steady, even growth, and needs to be free of knots, twist, and rot. In other words, suitable logs come from old, slow growing, but healthy trees. Since most forests in New England have been logged at least once, spruces that are suitable for tonewood are very difficult to find. But they are out there. Some of the most promising places are dense stands on north facing slopes and ravines in difficult to reach places. Trees in these areas are protected from the wind so are more likely to grow straight, and are difficult to access for logging so are more likely to grow large. The trees need to be grown in dense stands in order to keep their growth slow and to reduce branching and wind damage.
Because of their rarity, spruce trees with these characteristics are very valuable. A tonewood spruce log can be worth 10 to 20 times the value of a spruce destined to be made into 2 x 4s or other dimensional lumber. There aren’t a lot of these large, old, slow growing spruces around, so cutting them may seem more like mining the last of a resource rather than stewarding it for the future. However, tone wood quality trees can be purposefully grown, as is done in Switzerland and other high-altitude European forests. The key is to identify them early, keep them densely spaced, prune the bole, and track them over time. This of course is a multi-generational endeavor, since tonewood spruces are harvested at 200 to 250 years old. With today’s GPS and mapping capabilities, it’s much easier to keep track of these trees than in the past. Since it’s unlikely that a lot of landowners are going to identify and grow future tonewood trees, there will never be an excess of these trees available and prices will remain high. Demand far exceeds supply, with a long-term trend of increasing scarcity. Those that do grow these trees on purpose will be providing a significant financial benefit for future generations and can take pride in developing a highly valued material to be made into a beautiful musical instrument.
Making the tops
After the tree is identified and felled, the suitable logs are brought to the shop where they are cross cut into 24” long sections called bucks, then further split by hand into pie-shaped billets varying in number between four and eight per buck, with a tool called a froe. This tool is essentially a blade and a wood handle perpendicular to each other, which was historically used for splitting shingles and riving boards. The wood is split instead of sawn in order to closely follow the grain and preserve its integrity. Each billet is then sawn on a band saw into individual guitar top halves, with the grain of each piece oriented exactly perpendicular to its surface. The process of producing the tops requires much careful handling and attention to detail, gained through experience. They are air dried and stored between flat boards in stacks; these are called stock books. The wood from each tree is carefully tracked by its position in each log, so if a luthier (guitar maker) likes a particular set of tops, then the supplier can provide them with another pair from the same section of log. It takes two pieces to make a top, so they are sold in bookmatched pairs. (Picture butterflying a steak- a section is cut in half lengthwise, then the adjacent pieces are opened like a book, so the grain matches up.)
After learning more about tonewood, I wanted to see if I could find some suitable trees. I remembered a particular stand of large spruce where I once worked in Maine. There was a steep ravine and a lot of rocks, difficult to reach with logging machinery. When visiting the state in early March, I went out to see if I could locate these trees. I was able to find them, but as is true with many things, they were a little bit smaller than they were in my mind’s eye. But they were of decent size, so they may have potential for the future. The largest one I found had a 23” diameter, and it appeared to be clear of knots, but it’s hard to tell. The growth rings are probably narrow, given the poor soils in the area. So who knows, maybe a few years down the road the wood will end up in someone’s guitar, and the legacy of the tree will live on in the music.