(Opposite) Otomi woman using strips of jonote (Trema micrantha) bark to make a sheet of paper in San Pablito, Puebla, Mexico. Note the softened bark fibers hanging in the background, and the rectangular, flattened stone, or muito, used for pounding the bark fibers together.
San Pablito (N20°18´02´´, W98°09´45´´) in the Sierra Norte of Puebla, Mexico, 1984
I continued working at the research institute in Xalapa after I finished my doctoral research. One of my first projects, which represented a notable shift from my ecological work on the ramón tree, was focused on the bark paper trade in Mexico. These brightly painted sheets of handmade paper had long been a successful handicraft item for tourists, but several aspects of the bark paper supply chain had changed dramatically in recent years. My research uncovered a fascinating history of people and plant interactions, and provided a sobering example of how market conditions and poor forest management can lead to resource depletion.
Paper made from tree bark has been produced in various parts of Mexico for over fourteen hundred years. Bark paper played an important cultural role during pre-Hispanic times, and many indigenous groups developed papermaking technologies. The total quantity of bark paper produced in Mexico before the arrival of the Spanish was sizable. In the Codex Mendoza, a history of the Aztec rulers with a list of the tributes offered them each year that was written after the Spanish conquest, it was reported that over 480,000 sheets of bark paper were sent in annual tribute to the royal house of Moctezuma II in Tenochtitlán, the capital city (today’s Mexico City).1 After arriving at the imperial city, the paper was destined for use in religious ceremonies, to adorn temples and altars, and for codices. The paper appears to have been produced by roughly fifty villages scattered throughout the Aztec Empire.
The Otomi people first moved into the rugged mountains of northern Puebla around 800 C.E. and were conquered by the Aztecs in the late sixteenth century. One of the local Otomi communities, San Pablito, had an active tradition of papermaking, and this town was undoubtedly a major producer of the bark paper given in tribute each year to Moctezuma. After the Spanish conquest, the production of bark paper in Mexico gradually started to disappear. San Pablito was one of the few communities that continued to make the paper for use in agricultural rites, folk medicine, and witchcraft, although it is doubtful that large quantities were required to satisfy these ceremonial needs. The papermakers in San Pablito continued at a low level of production for several centuries.
But in the early 1960s things changed. An architect, Max Kerlow, and a painter, Felipe Ehrenberg, gave several sheets of Otomi bark paper to native artists in Guerrero renowned for their intricate, colorful paintings on clay pots and wooden masks. The painted bark paper sheets were received with enthusiasm, and in 1963 the first exhibition of painted bark paper was held in Mexico City. The exhibition was a great success, and the demand for bark paper paintings increased dramatically.
Today, bark paper paintings represent one of the most successful and widely distributed types of folk art in Mexico. They are sold in tourist centers throughout the country and exported in large quantities to American, European, and Japanese markets. The production necessary to satisfy the commercial demand for bark paper paintings exceeds a hundred thousand sheets in some months—more than twice the amount sent in annual tribute to Moctezuma II. The salient difference is that San Pablito is currently the only remaining papermaking center in Mexico, and this small Otomi village makes all the bark paper required to supply the enormous market. The drastic increase in demand over the past fifty years has produced several notable changes in the way bark paper is made in San Pablito.2
San Pablito is located deep in the mountains at the end of a steep and winding road. The town is very quiet. All that can be heard from most of the houses is the constant tapping of a rock on a board as bark fibers are flattened and fused together to make paper, even during the middle of the day, when everyone might be expected to be working in the fields. Not many young men can be seen around the village. Although the town seems to be doing well—it has a high school, electricity, telephones, and computers—all the younger men have gone to the United States to find work, leaving the women and children to pound out the bark paper and negotiate the contracts with the buyers.
The Spanish phrase for bark paper, papel amate, identifies it as paper (papel) made from the bark of fig (amate) trees, trees from the genus Ficus (Moraceae). The inner bark of fig trees provides the perfect raw material for making paper. The fibers are stringy and flexible and they can be easily separated after they have been boiled for a couple of hours. Once they are softened, they can be pounded together on a board with a flat rock to form a sheet of interlacing fibers that, after it dries in the sun, turns into coarse paper. Fig trees have the added advantage of being able to regenerate bark after it is stripped off. A single fig tree can be exploited repeatedly for bark fiber—as long as not all the bark is harvested at once and the tree is given sufficient time to recover between harvests.
Traditionally, about half a dozen different species of fig tree were used to make bark paper. Although fig trees are common components of tropical lowland forests, the forests surrounding San Pablito represent a transition between the tropical lowlands and the temperate highlands. The climate is humid, yet temperate, with a marked seasonality of rainfall and a pronounced drop in temperature at night. Fig trees do not generally thrive in this type of climate, and local forests contained only a few scattered individuals from the genus. As long as the use of paper in San Pablito was limited to witchcraft and other ceremonies, a sufficient amount of bark fiber could be obtained from these trees. When the demand for bark paper began to increase, however, the Otomi were forced to remove larger strips of bark and increase the frequency of collection. The bark was not allowed to regenerate, entire trunks were denuded, and all the fig trees in the forest eventually died.
During this period, the expansion of agriculture in the region prompted forest clearing so the inhabitants could plant coffee and citrus trees; pastures were also established and livestock introduced. Areas formerly in forest were soon covered with communities of fast-growing pioneer species. One of the most common weed trees found in these early successional thickets was jonote (Trema micrantha),3 and in the early 1980s the Otomi in San Pablito started making paper from this species. Although the bark fibers of jonote are thicker and more rigid than those of fig trees, longer boiling times and the addition of lime (calcium oxide) to the water were introduced to soften the fibers. In its favor, jonote occurs in dense aggregations, not as scattered individuals, and grows extremely fast. The bark can also be harvested throughout the year, in contrast to fig trees, which must be harvested at the onset of the rainy season to facilitate bark removal. The disadvantage of jonote is that the species does not regenerate its bark. A section of stem can be harvested only once, and if excessively long strips of bark are removed, the tree dies. The need for ever increasing amounts of bark fiber soon killed all the jonote trees in the vicinity of San Pablito.
The paper currently produced in San Pablito is made from jonote bark brought in by truck from the state of Veracruz, over 250 kilometers away. While a stack of painted bark papers for sale in a craft shop or the Mexico City airport may not seem noteworthy, an ordinary sheet of Otomi bark paper follows a long, complicated route before arriving at its final destination. The raw material is shipped from Veracruz, the paper is manufactured in Puebla, and the final painting is done in Guerrero. And perhaps more to the point, there is no amate in this papel amate.
Trees produce two types of cells: meristematic cells, which can divide and produce more cells, and structural cells, which provide support and transport water and nutrients to different parts of the tree. A single layer of meristematic cells, the vascular cambium, circles the diameter of a tree. As the cells in this layer divide, they produce one new type of cell, the xylem, toward the inside that conducts water and nutrients upward, and another new type of cell, the phloem, toward the outside that conducts the photosynthetic products from the leaves down to the rest of the tree. Given the volume of material that needs to be transported, the xylem cells, the cells that pump water, are produced in much greater quantity than the phloem. When bark is stripped from a tree, the tissue containing these cells is removed, and in some cases the single layer of meristematic cells also comes off. Without meristematic cells, the tree cannot regenerate its bark. If all the bark is removed from the stem of a tree, the tree will eventually die because the plumbing that supplies the sugars needed for growth has been removed.
The apparent inability to regenerate its bark was a major drawback in the use of jonote trees. I wondered whether protecting the bare trunk from desiccation after harvesting the bark might help stimulate the wound-healing process. If jonote trees were able to regenerate their bark, collectors could harvest them more than once, leaving a few sections of bark intact along the stem each time, so the harvest tree would not die. The bark resource could be managed on a sustainable basis, a new generation of jonote trees could be planted near San Pablito, and the critical link between artisan and raw material could be reestablished. The key was finding a way to promote the production of new bark tissue.
To test this idea, I located a dense stand of jonote trees near my office in Xalapa, stripped varying percentages of bark from several trees and then wrapped the trunks of some of the individuals in banana leaves and others in aluminum foil.4 Anatomical analyses of samples of the bark and wood from the harvest trees indicated that, in every case, I had ripped off all the meristematic cells when I stripped the bark from the jonote trees.5 The bare, exposed trunk, which I carefully wrapped to keep it moist, was composed entirely of structural cells.
Every two weeks, I would briefly uncover the trunks of the trees and take another wood sample. For the first six weeks, nothing happened. The tissue remained moist, but the wound that I created when I stripped off the bark had not begun to heal. During the next sample period, however, new tissue started to form. A layer of structural cells had divided and was producing new water-conducting xylem cells to the inside, and new photosynthate-conducting phloem cells to the outside. And new bark was growing along the edges of the wound. At the time, this seemed like magic.
An additional objective of my work at San Pablito was to try to reestablish a local source of bark fiber for the Otomi artisans. I had initially hoped that silvicultural techniques could be used to enhance the regeneration of the original fig tree populations in the region, but the scarcity and poor condition of existing trees made this plan untenable. After discussions with the villagers, it was decided to establish a plantation of jonote trees. This species is easy to propagate, attains a harvestable size in four to five years, and is well adapted to the high light conditions of a plantation; with careful post-harvesting treatment it will also regenerate its bark. The villagers would still have the option of planting fig trees, which are more shade tolerant, under the jonote trees after the canopy of the plantation had started to close. A nursery containing ten thousand jonote seedlings was established on the outskirts of San Pablito in 1984, and a local farmer donated a small tract of land to transplant the seedlings to when they reached sufficient size.
I went to Peru shortly after the nursery was established and have never revisited San Pablito. I am told that the production of bark paper continues to increase. New products like bark paper envelopes, lampshades, wallpaper, and faux parquet flooring have been developed, leading to chronic shortages of raw material. Apparently, nothing was ever done with the jonote seedlings. It is difficult to restore the relationship between a community and a plant resource, even one that has developed over centuries, once the resource has been depleted and the environment has changed, and people have largely forgotten the benefits of sustainable plant use.