The wood most commonly known and sold as Thuya Burl is known to botanists and other plant scientists as Tetraclinis articulata. This is the only species in the genus. T. articulata is now only found in very small areas of the Mediterranean, although it is possible that it once was more widely distributed given that it is one of the few conifers named in the Bible, in Revelations 18:12, where it is referred to by another common name, “citron wood.” Currently, the only known significant stands of T. articulata are found in Morocco, northern Malta, and southern Spain around the city of Cartagena.
T. articulata is more properly referred to as a shrub rather than a tree in most cases and it is rare to find an example large enough to yield actual timber. Instead, it is almost exclusively the underground burl, only found on mature trees that have endured multiple rounds of growth and destruction of the main trunk due to fire or over-grazing by sheep and goats. Young trees will not have burls. At one time, burls were only collected from dead trees and could only be discovered by digging into depressions left from trees that had died and rotted away. With a burgeoning market in Europe and North America, harvesters started to dig up living mature trees. This practice is fatal to mature trees. While the trunk can be harvested without killing the tree completely, as is explained below, burl harvesting is inherently fatal and this has led to dramatic reductions in available trees.
T. articulata is the national tree of the country of Malta, but only about 100 trees remain in the entire country, on the northernmost coast of the main island, Malta, the island from which the entire nation derives its name. The trees to be found in Spain occur in two separate stands, on either side of the northern reaches of the city of Cartagena. The population of these trees has recently grown from about 5,000 to over 7,000 due to regeneration after fires. As is the case with many conifers, T. articulata is adapted to fairly routine fire. Fire causes the seeds to open and become fertile and mature trees can regrow from the trunk, an ability known as coppice, rare among trees, so that even if a mature tree is burned severely it will regenerate from the trunk remnant. Routine fire suppression hampers the reproduction of the trees. Wild fires left to burn, when they do not threaten human habitation, are beneficial to the resurgence of this species.
There are a few trees, possibly, left in Tunisia and anecdotal reports exist of a small number of trees being found in Libya but this is not substantiated.
The majority of T. articulata burl material originates in Morocco where T. articulata remains relatively widely distributed over hundreds of thousands of acres in at least five different areas of the country. However, the government of Morocco has recently outlawed the exportation of T. articulata burl from the country due to massive overharvesting of living mature trees to meet demand instead of the more traditional, and sustainable, practice of collecting burls from dead trees that have completely rotted away. Objects made from T. articulata burl by artisans in Morocco may still be exported but the burl wood itself may not be exported any longer, at least not legally.
For the sake of simplicity and common understanding, I will refer to T. articulata from this point forward simply as Thuya Burl.
Thuya Burl is generally an orange or reddish brown color. As is true of many colored woods, the color tends to darken with age to a medium to dark reddish brown. Thuya is always exported and sold as burls from the root of the tree. The plain and unfigured wood from the trunk is of no to little commercial value. Typical features of burl wood, especially multiple failed buds that form “burl eye” figure are common and the more that are present the greater the retail value of the wood.
Thuya Burl blocks can vary in frequency and size of knot clusters, but grain is more or less always swirled and irregular. Thuya Burl presents with a medium to fine texture and good natural luster once properly surfaced and polished.
Because on the burl of the Thuya is harvested and sold, there is no end-grain.
While I cannot imagine it to be relevant for the common uses of Thuya Burl, it is resistant to rot and insect, including borer, attack. This resistance ability likely accounts for the survival of burls underground for years after the parent tree has died and decayed away.
Most any burl wood can be difficult to work and Thuya Burl is no exception. The difficulty arises from the highly figured and irregular grain of the material. Great care must be taken to avoid tear-out and the best way to ensure desirable results is to do all work, including any shaping and plane operations, by hand only. In addition, very sharp tools are required.
Once Thuya Burl is in the desired size and shape, it does sand and finish quite well, although as an oily wood, it will gum sandpaper quite quickly. Also, drills can be quickly clogged with oily material, so frequently withdrawing and cleaning the bit during longer bores is highly recommended.
Thuya Burl has a distinct and quite delightful cedar-like smell when freshly cut or turned. The odor is quite spicy and sweet and the wood is sometimes used as a source of fragrance or incense.
Most all burl wood, due to its relatively uncommon nature, sells for premium prices. Thuya Burl is one of the most expensive burl woods on the market today due to its very limited geographic occurrence, its popularity, and the banning of exports by the Moroccan government will drive already very high prices even higher. Thuya Burl is easily one of the most expensive exotic woods on the market today and prices will only rise as supply becomes more and more limited.
I always recommend both West Penn Hardwoods and Bell Forest Products as excellent sources of both domestic and exotic hardwoods. I have had multiple dealings with both vendors and have always been very satisfied.
West Penn Hardwoods sells Thuya Burl as unrefined burl blocks at the price of $22 per pound. Material of this type can have significant voids or other defects as it has not been cut or processed.
Bell Forest Products, as is true of most vendors, only sells pen blank, or similar small spindle, sizes of Thuya Burl. The lowest price piece, of ¾” x ¾” x 4 ¾” size is currently on sale for $4.50, with a regular price of $6.00 each. Quantity discount packs, with free shipping, are available as well.
Other potential vendors, most of whom I have dealt with at least once, include, but certainly are not limited to: Griffin Exotic Woods, Colorado; Cook Woods, Oregon; Exotic Woods USA, New York; Gilmer Wood Company, Oregon.
Thuya Burl is also available through Ebay, but I am reluctant to use this source for multiple reasons. Ebay vendors may, or may not, be reputable and may, or may not, follow legal statutes related to the importation and exportation of restricted woods. Also, very attractive prices are common on Ebay but ALWAYS be CERTAIN you understand shipping prices and policies before agreeing to purchase. Items selling for below standard market values often incur extremely high shipping costs, shown in small and faint print, to recoup the losses of selling below market price and value. Be absolutely sure you understand exactly what you are agreeing to purchase and exactly what the final costs will be before entering into the contract to buy.
Woodfinder is an excellent website that is dedicated to advertising exotic wood dealers. In your search for Thuya Burl, this can be an invaluable resource provided you use multiple search terms to capture all the possible listings. Alternative spellings of “Thuya” do exist and the most common is “Thuja” although others are possible. I can’t speak to the quality of any of the listed dealers, but Woodfinder does have the advantage of allowing searches to be performed based on location which might allow an interested buyer to visit a listed wood dealer near their home in person to hand pick nice pieces at a comfortable price.
Not surprisingly, given its rarity and very high costs to obtain significant quantities of the material, Thuya Burl is commonly used in applications that require very little material including: carvings, veneer, decorative boxes, turned objects, and other small specialty wood items.
Historically, resin from Thuya, known as sandarac gum, was, and still is, albeit against the prohibitions of Islam, used to make liquor. In Morocco, this liquor it is used as a remedy for difficult childbirth. It is has many other uses including the treatment of cramps, roundworm, tapeworm and insomnia. Its use against the ailments does not equate with effectiveness and no scientific studies have been performed to validate, or dispute, these folk remedy uses, although it is important to note that recognized effective treatments such as narcotic pain killers, aspirin, and anti-malarial medications, amongst many others, started out as “folk remedies.”
At this time, Thuya Burl is not listed in the Convention in International Trade in Endangered Species of Wild Fauna and Flora (CITES) Appendices, which would limit its trade internationally. Thuya Burl is listed on the International Union for Conservation of Nature (IUCN) Red List as being a species of least concern.
However, the small subpopulations in Malta and Spain are both regionally endangered and highly protected by those respective governments.
The ban on exportation of Thuya Burl by the Moroccan government complicates the availability of this wood for the future, but it is critical to note that without an injunction against world trade imposed by CITES, the purchase, trade, selling, or other acquisition of Thuya Burl outside of Morocco is in no way legally impeded at this time. This could change, especially if Morocco were to petition CITES to list Thuya Burl in some manner, which has historical precedent given that Nicaragua successfully petitioned CITES to list their limited stands of Dalbergia stevensonii (Honduran Rosewood).
I confess that I have long been aware that Thuya Burl is under pressure from overharvesting in Morocco but as the material was already harvested and sold I didn’t personally feel that I was placing undue pressure on the species by purchasing small lots of pen blank sized pieces that were not directly imported, against Moroccan rules, from Morocco. However, I might not choose to purchase this material again in the future.
I realize that inherent in working with wood is the killing of a part of the natural world that may be slow to return and if I become deeply concerned about this fact, I will have to find a new hobby. I hope that such a time does not come to pass or at least not any time soon. I am also very confident that the vendor from whom I purchased my stocks of Thuya Burl sourced their material legally and responsibly. In part because I am concerned about legally and responsibly obtained exotic wood, I am reluctant to buy from sellers outside of well-established and known vendors. I am highly unlikely, for example, to purchase exotic wood from auction sites, such as Ebay, because of uncertain sourcing and documentation, as well as the potential, even likelihood, of material being misidentified in order to achieve a higher selling price.
I also realize that many, if not most, wood workers do not have endangered species lists memorized, therefore I think it worthwhile and important to do even a small amount of research before purchasing any lumber, domestic as well as imported, to be certain of the potential impact you are having, even in a small way, on threatened or endangered populations. This information is easy to come by and takes only minutes to locate through any Internet search engine, including those you can access on your phone as you are standing in the lumber yard or store. Unfortunately, you simply cannot count on a vendor to tell you a product they are selling is endangered.
Although severe reactions are quite uncommon, Thuya Burl has been reported to cause eye and skin irritation.
Appropriate protective equipment is therefore recommended, as always, when working with this, or any other, exotic or domestic wood, unless you have worked with the species before and are certain you are not sensitive to it. Complete information about health hazards associated with a wide variety of hardwoods is available from The Wood Database.
In addition, the known risks posed by prolonged and repeated exposure to dust from any wood species are still present when using Thuya Burl. Additional information about how to best use a dust collection system and personal protective equipment, such as respirators, can also be found through this excellent and comprehensive resource.
Fortunately, I experienced no negative side effects when working with Thuya Burl.
My Personal Experiences
I have worked with Thuya Burl in the past and it remains one of my favorite woods to use because of its unique beauty, its high luster due to the natural oils, and because it smells so incredibly delicious when freshly cut or turned.
In my experience, the wood turns absolutely beautifully, provided you are patient and use sharp tools to counter the difficulties inherent in any highly figured burl wood. The wood cuts so cleanly that little to no sanding is generally required which is helpful because the oily nature of the wood quickly renders sandpaper, as well as newer sanding screen technology, useless due to gumming and clogging. While I do usually apply a standard pen finish to the Thuya Burl pieces I have made, the oil content means that the wood can simply be buffed at high speed to achieve a high sheen natural finish if desired. Thuya Burl is on my short-list of very favored woods to work with.
While I would love to work with Thuya Burl in a bowl size, even a small bowl, prices are simply prohibitive. Single burls sell for hundreds of dollars, sometimes well into the thousands depending on the size of the burl piece, and I can’t bring myself to commit that amount of cash into one piece. Now, that said, if someone were to feel compelled to give me a large Thuya Burl that would be a completely different matter, although I don’t see that happening in the near future. But if it should, I’m just saying…
Given the export restrictions imposed by the Moroccan government, the source of almost all Thuya Burl, it is essential to be as certain as possible that the source from which the material obtained is acquiring stock legally and in full accordance with Moroccan law. To do otherwise is to further endanger the material and to potentially cause even stronger restrictions to be imposed, as well as placing continued unsustainable pressure on a rare natural resource. As long as poverty and desperation continue to exist in significant portions of the Moroccan population, it can be expected that the export rules will be circumvented whenever possible. Buyers beware and follow your own conscience.
As always, I wish all my readers a great experience in whatever their wood working interests happen to be and to those who like working with lathes especially, do a good turn today!