Scientific Classification of Thuya
Thuya (alternatively known as Thuja) Burl comes from a tree that is the only known representative of its genus, Tetraclinis articulate. This single species within a genus is identical to humans, who, as members of the species sapiens, are the only members of the genus Homo. Tetraclinis trees are members of the Cypress family of trees, many of which grow as ornamentals in American yards. Some may also refer to Tetraclinis as Sardarac.
Geographic Distribution of Thuya
This tree is native to northwestern Africa, specifically to the Atlas Mountain regions of Morocco, Algeria, and Tunisia. In addition, this tree can also be found in very isolated pockets of southeastern Spain as well as on the Mediterranean island nation of Malta. The tree appears to prefer a hot, dry, subtropical climate and grows at low altitudes.
Physical Appearance and Properties of Thuya
The hard heartwood varies in color from a glistening golden brown to a dark hue that is almost black. The Thuya wood tends to display a figure called “eyes” which are perfectly round and scattered throughout some burls, while in others they are clumped together in what appear to be islands of eyes. The figure is similar to bird’s eye maple but the overall effect is much darker and easier to discern. The wood is oily and very aromatic with an incredibly pleasing scent reminiscent of pine and black pepper.
Uses of Thuya and Its Burlwood
The resin of the Thuya tree can be used to make varnish and lacquer. These substances are most valued for their use in the preservation of paintings. The burl wood in particular is in great demand by woodworkers and wood turners for its peculiar beauty. Its use is limited to turned wood objects such as turned wood pens or bottle stoppers, although it could be used for other small decorative purposes such as knife grips.
Cautions for Woodworkers Working With Thuya
As with any oily wood, gluing may be difficult unless the oily resin is removed from cut or drilled surfaces with a mineral spirit immediately prior to the application of the glue. The wood is quite brittle and tends to break distressingly easy, so care must be exercised when working with this increasingly rare and costly wood.
What is a Burl Anyway?
A burl is a tree growth in which the grain has grown in a deformed manner. A burl results from a tree undergoing some form of stress. Most burls grow beneath the ground, attached to the roots. Almost all burl wood is covered by bark, even if it is underground. Insect infestation and certain types of mold infestation are the most common causes of this condition. Because this creates highly unusual and beautiful grain patterns, burl wood is often highly prized by wood turners and craftsmen. Finding thuya burls is difficult because in most cases the tree itself has been removed long ago, meaning that those who search for the burls must have an in depth knowledge of surface soil signs that can guide their digging to the most likely locations of hidden thuya burls. High demand and the difficulty in unearthing burls make them a fairly expensive option.
My Experiences Working With Thuya Burl
In my experience working with Thuya has been a mix of the heartbreaking and maddeningly frustrating along with joy and pleasure. Thuya is incredibly brittle, and since it commands a premium in the exotic hardwood market, having a piece break while drilling it is a sad and potentially infuriating experience. As you can guess, it has happened to me! The best ways I know to prevent this from happening are to use very sharp tools, use the slowest possible settings on machinery working the wood, and above all else, BE PATIENT with the Thuya Burl. It will reward you if properly worked.
Thuya wood smells wonderful when drilled or turned, a mixture of pine and spices that is simply indescribable, you have to experience it to understand it. The wood turns beautifully, as many oily woods do, and again in part because of the oily nature of the wood, finishing the wood can be as simple as buffing the natural oils or applying a light wax coat. The wood will shine and practically glow when completed. I find that a careful pass with a skew chisel gives a better final finish than any light grade of sandpaper can accomplish. Plus, the heavy oil of the Thuya Burl will very quickly clog sandpaper, increasing the very real risk of burning the wood you have invested time and effort into drilling and turning. Goes easy on finishes and sanding with Thuya, it will be beautiful as it is!