By Miranda Wilson | From the May-June 2022 issue of Strings magazine
Pernambuco, the heartwood of Paubrasilia echinata, is renowned as the perfect wood for making bows. At one gram per cubic centimeter of wood, its density makes it the ideal weight for the standard violin bow (60 grams) or cello bow (80 grams). It is remarkably elastic, being able to tolerate the process of cambering, in which the stick is subjected to dry heat to create its curve. A fine pernambuco bow can create crisp attacks, beauty of tone, and a good “bounce” in off-the-string bow strokes. If maintained with care, it will last for centuries.
What many string players don’t realize is that pernambuco is becoming increasingly rare. The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) now categorizes pernambuco as “Appendix II.” What this means is that while the tree is not necessarily in imminent danger of extinction, it must be strictly regulated so that it does not become so.
How and when did pernambuco get so endangered? Deforestation of pernambuco is not a new problem, having begun more than 500 years ago. When the first 16th-century Portuguese explorers landed in Brazil, they immediately noticed pernambuco for its similarity to an Asian tree species prized for its use in making fabric dyes. The deep orange-red of the structural tissues in the tree’s stems and roots made it valuable for trans-Atlantic trade.
Though the wood and dye created riches for Brazil’s European colonizers, the pernambuco industry also caused immense human suffering. Indigenous workers were compelled into hard labor, later joined by enslaved people from Africa. The environmental costs have been extreme, with an estimated 93 percent of the original forest now gone. Over the centuries, various governments attempted to regulate the industry to prevent further deforestation, but the tree is still in danger.
Simply planting more trees is not straightforward. Pernambuco will grow only in Brazil’s Atlantic Forest and needs to be planted among other species in a secondary forest vegetation environment to flourish. Noting these difficult conditions, a group of concerned environmentalists and musicians decided to act. Spearheaded by New York City bow maker Yung Chin, they formed the International Pernambuco Conservation Initiative (IPCI), a nonprofit dedicated to making pernambuco sustainable. The organization’s members agreed to commit to “a self-imposed moratorium on any new wood purchases until inventories of pernambuco forests have been completed and conservation plans that will enable the sustainable use of pernambuco by future generations have been implemented.”
At present, supplies of pernambuco are sufficient for bow making to continue. Some makers, however, are investigating the use of other woods in the event that it eventually becomes unavailable. Leading the way is New Jersey bow maker John Aniano. As a member of the IPCI’s alternative wood committee, he has spent many years creating bows from other, less endangered species. The quality of his work has earned him several awards from the Violin Society of America, including a gold medal for his inlayed amourette viola bow in 2010. “Amourette is one of the materials used in early bow making,” Aniano says. “It’s also known as unfigured snakewood. It has a higher strength and lower density than figured snakewood, which isn’t so easy to work with.” Taken from the heartwood of the Brosimum guianense tree, amourette is not currently on an endangered species list. It has a few disadvantages, such as its flexibility. “Generally, a snakewood bow is stiffer than a pernambuco bow,” explains Andy Fein of Fine Violins in St. Paul, Minnesota. “They tend to work well for more advanced players.”
A relative of Brosimum guianense also used for bows is Brosimum rubescens, known variously as bloodwood (for its red color) or cacique. Aniano considers it less successful than amourette for bows: “It looks good as a veneer, but it doesn’t have the density and strength.” He has had more success with woods from the Swartzia genus, such as wamara.
The most promising alternative wood so far is ipê, a member of the Handroanthus genus. Like pernambuco, it is also used to make dyes, though its color is yellower. It is similar in composition to pernambuco and, crucially for the cambering process, tolerates heat well. “The strength, density, and elasticity of pernambuco make it ideal for this process,” says Aniano, “but ipê can handle it, too.”
So why isn’t everyone switching to ipê?
“There was a complaint among makers,” says Aniano. “During the cambering process, ipê wood exudes a crystalline wax similar to paraffin. There was some pushback because the makers didn’t like the smell.” While the odor was not toxic, it was unpleasant enough to be off-putting.
There are other obstacles, which Aniano describes as more psychological than physical. “Pernambuco bows are ingrained in the music profession,” he explains. “Since the nineteenth century, everybody wants pernambuco. Substitute woods are a hard sell. When you’re the maker, you aren’t making bows to hang on the wall. They’re a tool.”
The density of wood is a big part of the problem. Some makers actually discard pernambuco with a density less than one gram per cubic centimeter. As astonishing as it seems to waste this rare and precious resource, it makes business sense. “A cello bow of 76 grams might not sell,” Aniano says. “If you stray outside of any of the boundaries, you’ll have trouble selling.” While it’s possible to make a bow from lower-density wood in a slightly larger size to get the balance right, many makers don’t want to. “Some of them have a ‘recipe’ with all the sizes of their bows, and they don’t want to deviate,” Aniano explains. Players, too, are resistant to change. “As a bow maker, it takes just as much, if not more time to make a bow from an alternative wood, except for maybe ipê. If there is any hesitation on the part of players to try and/or buy alternative wood bows, that’s time and money down the drain if sales fall through.”
If players could be persuaded to give ipê and other alternative woods a chance, would a slightly non-standard size create any physical problems in playing, such as the bow not bouncing?
Aniano, who has a background in material science engineering, doesn’t think so. “People should think outside of the box,” he says. Violinists and cellists may have a hard time accepting non-standard bows, though violists are more open to alternatives because the viola itself is a non-standardized instrument. In response, makers are more willing to create viola bows from alternative woods. With violinists and cellists, alternative woods are still a hard sell, therefore fewer alternative-wood bows are available.
By most accounts, the string profession looks like it’s not quite ready for alternative-wood bows. But what will happen if CITES one day decides to move pernambuco to Appendix I? The 2016 ban on elephant ivory, an Appendix I material, created panic that older bows would be confiscated at border crossings. While makers can replace ivory tip plates with non-banned materials, what will they do if the sticks themselves end up on the no-fly list?
“Every country will be on the lookout,” says Fein. “Obviously, [if pernambuco becomes an Appendix I material] don’t take it out of the country or attempt to cross back into the U.S. with [a pernambuco bow]. Know the laws before you go. Get a carbon fiber bow or an alternative bow to use when crossing borders, and make sure you have a receipt and a certificate from a dealer or expert stating what your bow is made from and that it is not made from pernambuco.” Hopefully with conservation efforts, this will never be a reality.