One of the biggest choices in guzheng manufacture is the woods that are used to create the instruments. Thanks to incredible work by Carol Chang of ChineseZither.net I have below a brief overview of the types of wood you might find and a guide on why words like "Sandalwood" and "Wutong" aren't as meaningful as they might seem.
Any wood can be used to make a musical instrument - but the woods listed in each section make instruments known for their sound.
The main wood used in modern soundboards is Paulownia elongata or Lánkǎo Pāotóng (兰考泡桐). It's a fast growing tree that was planted in large numbers in Henan province's Lankao county (兰考) in about 1965 to act as a windbreak to control dust and preserve farm fields. Someone realized it could make fine lumber for musical instruments, and suddenly the dust control measure became a money maker. (*)
But what about pre-1965 zhengs?
Paulownia fortunei or Báihuā pāotóng (白花泡桐) was a popular pre-1965 wood for instruments. It's from the same genus as the P. elongata and is still touted as the wood used in the qin.
Cunninghamia Lanceolota or Shānmù (杉木) is used for zhengs made in the Chaozhou style, named for what is now a city in Guangdong province in southeast China.
"Hey!" I hear you cry "What about 'Wutong wood' and 'Firmiana simplex'?? I see that everywhere!" Well, there's a (long) answer for that. I hope you brought snacks.
Common names, imprecise naming, and mistranslations make figuring out actual wood species a real challenge. Thankfully Carol Chang of chinesezither.net put in the work and I am eternally grateful to her for that. Let's get some terms out of the way:
Paulownia: That's a genus of tree with 8 accepted species and 18 Latin synonyms. Synonyms are proposed names that turned out to refer to an already-identified species.(1) Only some species are used for musical instruments.
Tóng (桐): A category of wood. The 1051 CE book "Tong Guide" (桐谱, Tóng Pǔ), the earliest reference I know of, lists six varieties of Tong. Only some of them are in the Paulownia genus, so "Tong" is not a direct equivalent to Paulownia. (2)
Pāotóng (泡桐): Modern Mandarin name for Paulownia.
Wútóng (梧桐): A name often given as the wood used in guzheng, but covers multiple species. A common translation for Wútóng is Firmiana simplex, but F. simplex is not the most popular wood used for guzheng soundboards (that honor goes to Paulownia), and the most knowledgeable source I have on this, Carol Chang, says F. simplex is a poor choice for a soundboard. Further evidence of these confusions come from ancient records. Those that praise "Wútóng" trees for their instrument-quality wood mention purple flowers. F. simplex flowers with green, yellow, or white-tinted blossoms. The only modern English language source I have that goes into detail about the construction of guzheng says that the Wútóng used in Taiwan for instruments is both Firmiana simplex and an unknown species of tree from Canada, where F. simplex cannot survive.
At one point in history Wútóng could well have meant a particular species. It is, after all, listed as one of the six woods in the Tong Guide. In the modern day though it's used in at least three ways:
The people in Shanghai use Wútóng as shorthand for Fàguó Wútóng (法国梧桐, Fàguó = "French") to refer to Platanus × acerifolia, a hybrid tree created in Europe and imported by the French to Shanghai.
People in Northern China use Wútóng as a generic term for multiple varieties of Paulownia-genus trees.
People in Southern China use Wútóng to refer to Firmiana simplex, a tree that grows poorly in northern regions.
More on Tong Woods
Here are 11 names for Tong woods you might encounter:
Báitóng (白桐, "White Tong"), Báihuā tóng (白花桐, "White flower tong") and Báihuā Wútóng (白花梧桐) are all equivalent to Báihuā Pāotóng (白花泡桐), which is Paulownia fortunei.
Fàguó Wútóng (法国梧桐) 'French Wutong', a tree in Shanghai, refers to Platanus × acerifolia.
Gāng tóng (冈桐), Paulownia tomentosa, also known in Chinese as Zǐhuā tóng (紫花桐) or Rìběn Pāotóng (日本泡桐, "Japanese Paulownia")(3). Ancient texts suggest this could also be a good wood for instruments. It is frequently cited in modern times as prime wood for Japanese Kotos and Korean Gayageum, and is cultivated widely, including in the United States and Turkey(7).
Qīngtóng (青桐), Firmiana simplex, also called Wútóng (梧桐) in some places. Explicitly called out in a few ancient Chinese sources as a poor choice for musical instruments.(5) Mei Han 2013 also references Firmiana platanifolia; this is an accepted synonym for Firmiana simplex. (6)
Yóu tóng (油桐), Vernicia fordii or the "Tung Tree". Its seeds can be used to create Tung oil which is used in some varnishes for musical instruments. I don't have evidence the wood was ever used to construct them.(4)
Soundboard Footnotes and Sources
Chinesezither.net, Soundboard Woods article
Efloras.org, Flora of China database
(*): One source I found claims Mongolian zhengs, possibly Yatgas (雅托葛), have soundboards made of 杨木 or Yáng mù, which one source specifies as Liriodendron tulipifera. I haven't confirmed this elsewhere yet so this lives in the footnotes for now.
(1): Search results for Paulownia names from ThePlantList.org
(2): Text of 侗谱 from Wikisource Chinese, summarized in English by Carol Chang on her website.
(3): 毛泡桐图片 page (badly translated as "Pictures of Hairy Paulownia") on YuHuaGu.com. See names in header next to 别称, "Nicknames". Paulownia trees grow fine hairs on parts of their surface.
(4):Handbook of Materials for String Musical Instruments by Voichita Bucur, Switzerland: Springer, 2016, page 388
(5):One modern source that decries F. simplex as a poor choice for instruments is "古典詩文中的桐樹意象與文化意涵, The Symbol and Cultural Connotation of Phoenix Tree" by Ming-Yi Chou, contained in Volume 32 of the Minghsin Journal, published August 2006.
(6): Referenced on ThePlantList.org
(7): M. Hakan Akyildiz, Hamiyet Sahin Kol (2010)"Some technological properties and uses of paulownia (Paulownia tomentosa Steud.) wood", Journal of Environmental Biology (India), 31 351-355
Unfortunately Cheng 1991 is the only one of my sources to describe the woods used in the backboard. He mentions Mulberry, Elm, Catalpa ovata, Phoebe nanmu (a synonym for Machilus nanmu), and Paulownia. Mulberry and Elm aren't particularly helpful as they could be common names of individual trees, common names for categories of trees, or translations from Chinese. The other two are specific species but I have yet to find good references on their usage or value. Sources only offer descriptions of the plants themselves. That leaves me with these names:
Catalpa ovata, also known as Chinese catalpa, Yellow catalpa and Japanese catalpa.(7) The Chinese character 梓 may refer to it but I doubt that's a specific term.(8)
Phoebe nanmu is cited in Cheng 1991. P. nanmu is possibly confused with another species used in guzheng frames, Phoebe zhennan, as some english references use nánmù (楠木) to refer to P. zhennan (9). Diān nán (滇楠), which could be expanded to Diān nánmù (滇楠木) refers to P. nanmu, and suddenly we're talking in circles (10). Some english-language articles claim one or the other were used in the construction of the Forbidden City, but no article states both were, hightening my suspicion that these woods are confused for each other. Send me an email if you have more sources for me!
All parts of the guzheng affect its sound. That goes for the woods used in its frames and ornamentation as well as the soundboard.
Because the frame also has a lot to do with the look of the instrument, wood choice is many and varied. Below is the list of woods compiled from Carol Chang's work at chinesezither.net. Woods that aren't on this list could certainly be used, but these are the ones you are most likely to encounter. If you can find me proof of other woods being used, ideally with 汉字 or down to the genus and species names, I would be happy to add them!
Before we get into it we have to go over some more vocabulary.
Hóngmù (红木): Literally "Red Wood" it's a generic term used when the particular species isn't important. Entry level instruments are often labeled Hóngmù. Dictionaries translate hongmu as Rosewood or Mahogany. Mahogany is native to the Americas, so I can almost guarantee it's not going to be found in entry-level instruments made in China. As for Rosewood...
Rosewood is an over-used catchall. Officially, "Rosewood" refers to trees in the Dalbergia genus, many of which are used for instrument construction. In actual use, the name "rosewood" has been applied to anything with qualities somewhat similar to a Dalbergia. Over time this has included species in the Pterocarpus, Machaerium, and Dysoxylum genera. Without any other information, the term "Rosewood" can't tell you what type of wood the instrument is actually made of.
Sandalwood: In the English-language guzheng world, "Sandalwood" is used to represent Pterocarpus, Dalbergia, and Bobgunnia species - but actual Sandalwoods, such as those known for their fragrance, are of the Santalum genus. Many countries in Asia and the Pacific have native Sandalwood varieties. China has a few cultivated species, but I do not believe them to be native (11).
Zǐtán (紫檀): Can refer to multiple high-quality woods. If the wood is only listed as "Zitan" it is probably Madagascar Rosewood, Dalbergia baroni, or East Indian Rosewood, Dalbergia latifolia. It also makes up part of the name of the highly prized Red Sander, Pterocarpus santalinus (Xiǎoyè zǐtán) and the highly illegal Brazilian Rosewood, Dalbergia nigra (Bāxī zǐtán), but I would expect Brazilian Rosewood to be highlighted if it was used in an instrument. See their entries below for more details.
(11) "SANTALACEAE" by Xia Nianhe (夏念和) and Michael G. Gilbert, Flora of China Volume 5, p 208-219. 2003.
Movable bridges are made of hard woods with a high density as this transmits the sound better. Each wood transmits sounds slightly differently allowing for a range of effects to the timbre. Dalbergia species are the most common. I've seen bridges advertised as being made of unidentified hardwoods, unidentified rosewood, African Blackwood, Thailand Rosewood, and Zitan wood, the last three of which are all Dalbergia species (see below). As a point of price comparison, if generic hardwood bridges retail for $X then generic rosewood go for about $2X, and African Blackwood bridges cost about $3X. The precious woods jump in price both because of the wood and because the string rest material is often more expensive as well. A brief survey on Chinese online marketplace finds high-end bridges are sold for as much as $24X the cost of a generic bridge set.
There are mentions of bridges made of ivory or jade though I have not found definitive sources. There are modern day efforts to perfect hollow ceramic bridges, and I've seen low-end instruments with plastic ones, but wood remains he most common.
There are at least 3 woods used in soundboards, 2 others used in backboards, and 16 woods used in guzheng frames. Each of the woods lends a different tone to the instrument, descriptions of which you can see on Carol Chang's article.
Each entry starts with an English name, their genus and species, their actual Chinese names, and their pinyin. When a wood species has multiple English names I create an entry for each. Entries with "" are improper synonyms or the semi-literal translation of their Chinese name. I've also included three other pieces of information: First, a ranking to give a general sense of which woods are used on more highly-valued instruments. 1 indicates use on entry-level instrument. Woods with a 5 are used for fancy, high-quality instruments. It's possible a higher-quality wood could be used at a lower level, but I'd expect the specific piece used was of a lower quality in some way or had been mislabeled.
Second, I've included the wood's status on the International Union for the Conservation of Nature's Red List of Threatened Species or the Catalogue of Life. Not all woods are on this list, but many are.
Third, I've included the wood's status on the "Convention on International Trade in Endangered Species" (CITES) if it is listed. If a wood is listed on CITES it requires extra paperwork to cross international borders. Products made of one species in particular, Brazilian Rosewood, Dalberia nigra is not allowed to cross borders, period. The technical details are available on the US Fish and Wildlife Service's website. For the significance of these listings, see the Issues section at the end. All Dalbergia species are in CITES. Dalbergia nigra: CITES Appendix I, (heavily restricted). All other Dalbergia: Appendix II (commercial restrictions).
Import Issues, CITES, and Red List Status
First on Brazilian Rosewood, Dalbergia nigra: It's listed as Vulnerable by IUCN yet has the highest level of protection in the CITES agreement, Appendix 1: Trade of any part made of this wood created after 1992 is illegal. Part of that may be political; part of it may be future-looking. Demand was high, yet it's having significant problems re-seeding. Fast removal and limited regrowth is a recipe for extinction, hence its listing.
Now on to the larger discussion of all these threatened listings.
The IUCN's Red List is a database, a resource. Like our frenemy Wikipedia it's a reference with no legal authority. The CITES agreement is the next step up. It is not itself a law, but if your country agreed to it then they have agreed to enforce it through their own laws. If you're in one of the 183 countries that upholds CITES (spoiler alert: you probably are) then CITES will tell you which animal and plant products need special permits.
The full name for CITES is "the Convention on International Trade in Endangered Species of Wild Fauna and Flora". First drafted at a 1963 meeting by members of the IUCN, It was first agreed to by 80 countries in 1975. The intent was to restrict trade in plants and animals that were endangered so as to keep those species alive longer. The list of species protected and the extent each is protected changes periodically.
January 2017 saw the addition of all woods in the Dalbergia genus to the CITES agreement. Dalbergia nigra, Brazilian Rosewood, had already been added to the CITES agreement in 1992 under Appendix I protection. Some previous Dalbergia species had already been on the list with Appendix II protection. There is an Appendix III but no guzheng-relevant species are currently on it.
You can read the full explanation of CITES on its website, here. In the USA it's administered by the U.S. Fish and Wildlife Service. They list every species currently protected on their web page here and provide a lengthy discussion of issues relating to crossing borders with such items as part of a public letter, here.
To help in your understanding, below is an overview. Make sure you read to the end.
CITES and You: Grandfathered Instruments
There is one key thing for collectors, buyers, and sellers to know about CITES and guzheng: It does not restrict woods retroactively. Wood that was used prior to the date the species was added to the agreement are exempt. This date is called the "Convention Date". If you can prove that your guzheng was produced prior to 1992 (if Brazilian Rosewood) or prior to 2017 (for most other Dalbergia species) you might have more leeway in buying or selling the instrument. If you have questions, contact your country's customs, border, or conservation agents.
CITES and You: Buying Internationally
In order to cross a border, that is to import and export an item made of a protected species, the person responsible must apply for permits with evidence the creation of the item did not negatively impact the species. That law is aimed at companies. If you are buying a guzheng or other item that is made of protected woods from another country, it is the seller's responsibility to apply for and file all the relevant paperwork both as an exporter from their country and an importer to yours. But as a buyer, realize that if the international retailer doesn't file the proper certifications and your purchase gets impounded at a border crossing, you might be without both your money and the instrument.
CITES and You: Buying Domestically
The big sigh of relief: If the guzheng is already in your country the seller does not have to file for CITES-related permits. You can just buy it. Yay! In the case of many European countries, borders are often ignored. If the instrument is already in an European country and the the buyer is in an European country, no CITES permits should be required. Yay! Please note: I use "European" generically. You'll have to look up the trade agreements between the relevant countries to be safe.
CITES and You: Traveling with Instruments
The American League of Orchestras has a thorough breakdown of how CITES affects traveling musicians on their website. But if you need a quicker summary:
At the bottom of the U.S. Fish and Wildlife Service web page is the very important Appendix II, Annotation 15: "All parts and derivatives are included, except:... b) Non-commercial exports of a maximum total weight of 10 kg. per shipment". This means that if the total weight of protected woods used in your instrument are less than 10kg AND it's being shipped for a non-commercial purpose, you're fine! You have to prove that it's a non commercial export, but hey, at least it's possible!
The most likely way someone would take advantage of this would be to travel with the instrument. Maybe you're moving, maybe you received a gift while visiting with a friend, maybe you traveled to a country, bought a guzheng, and are now bringing it with you to keep. However it happened, once you become the owner of the instrument and you have no intent to sell it, you are export/importing it for a non-commercial purpose.
You still have to document ownership, point of sale, and do your darnedest to certify that the instrument does not break any laws - but it is perfectly permissible to cross borders with an instrument if it is for your own personal use. Also note: Duties may still be due. If you bought an instrument in one country and are bringing it to stay in another country, you'll probably need to pay a duty as you cross the border. If you need to cross borders frequently, some border control organizations offer 'passports' to prove you've already paid all relevant taxes. The USA version is about $75 and takes 2-3 MONTHS to get approval. It's intended for musicians living in the US who travel internationally frequently. Plan ahead.
The Larger Impact of CITES and Endangered Species
Guzheng importing is going to get interesting. Quality woods are typically harvested and dried for several years prior to usage in an instrument. Theoretically, the date it was harvested is what would determine if it was a Pre-Convention piece. With Dalbergia at large added to CITES in 2017, I estimate the mass market will run out of pre-convention timber by about 2022, save for low-output makers with significant stocks. At that point, what happens? I honestly don't know. CITES is written such that Scientific Authorities of the relevant countries can certify the wood was harvested in such a way that it did not damage or threaten the continuation of the species. Perhaps countries with money in the mix continue certifying woods for export without vetting the impact. That adds some paperwork and logistical headaches, but keeps business as usual for all of the good and bad that entails. If that happens, species populations continue to decrease and we see shortages in future decades.
If people are serious about conserving the threatened and endangered species and thus kept their standard for certification high, supply of woods would decrease, forcing price up. There is room for that in the guzheng market. We are spoiled with absolutely wonderful instruments for less than $1000. The owners of cellos, violins, and other fine western instruments can tell you - compared to their $3,000, $5,000, and $10,000+ medium-grade instruments, we are well off. While I hope prices for entry-level guzheng never mimic that of the cello or violin, the US market could stand the price increase.
A higher price would be unpleasant, but if it meant that in 20 years we'd still have wood readily available and thus quality guzheng at a reasonable price, it would be well worth it. Remember, unlike violins guzheng tend to lose their finer sound qualities with time. There is a pressure on guzheng players; we're all going to face this.
As to what you should make of all these woods being listed as having some cause for concern, well. It's important to know what impact we have on others. Yes, you can buy instruments made of endangered species, but by doing so, you are contributing to their destruction. Do you really want to be part of the reason why a future generation can't experience the the joyful sounds or appearance of some of these fine woods?
You have a few choices:
Option 1) Buy instruments that aren't made of endangered species. African Blackwood, African Padauk, Burmese Padauk, Bubinga, and Pau Rosa are Not Threatened and are used on medium and high-quality instruments. You can still get a beautiful instrument that sounds and looks amazing without contributing to the extinction of a species!
Option 2) Make sure your seller/producer is harvesting sustainably cultivated trees. If they own their own or buy exclusively from tree farms that use the same land to grow and regrow their tree crops, then you can rest assured they are not having a net damaging effect. Going out into the wild and cutting down trees? Not so good. Yes, this is a harder option, but if you are up to the challenge you'll rest assured.
Option 3) Contribute a sizable amount of money to conservation efforts specifically aimed at restoring the populations of trees that your instrument is made out of. I'm talking 30-50% of the cost of your instrument. Big money. By buying that instrument you are creating an economic pressure to cut down more trees. You have to create an even greater economic pressure to counteract that and keep trees standing or get new ones planted. The most cost-effective way would be to buy a tree, to give someone enough money so that the tree is more valuable if left standing. I don't know how to do that, practically. Giving to conservation and regrowth efforts is another option, but every step you are removed from the actual laborer cutting down the tree, the more of your money gets shunted off into bureaucracy and the less get's to the actual worker. Therefore, you'll have to give a greater amount to actually get enough money to that forester and its company to convince them to change how they harvest.
Option 4) Help expand the types of woods that are considered for guzheng production. There are many species with interesting qualities out there, even some in the USA. Remember, the soundboard is not made of an endangered species, it's the framing that's the problem. There is more leeway in acoustic properties in the frame. There must be nontraditional woods that will create an enjoyable sound! If you know an instrument maker who is up to the challenge, encourage them to try a build and post their results to instrument maker's forums, or get them in touch with me! The more interest there is in trying something different the better chance we have of ensuring a positive future for the instrument.