Among ribereños in the Upper Amazon, there is a body of traditional lore regarding both the uses and the administration of a relatively large number of Amazonian medicinal plants. My jungle survival instructor, Gerineldo Moises Chavez, who made no claims at all to being a healer, knew dozens of jungle plant remedies, including insect repellants, treatments for insect bites, snakebite cures, and antiseptics.

Most ribereños know, for example, that the latex of the sangre de grado tree (Croton lechleri) can be used to stanch wounds and stop bleeding, both internally and externally; that an infusion of the leaves, bark, or roots of chiricsanango (Brunfelsia grandiflora) can be used to treat fever; that chuchuhuasi (Maytenus macrocarpa) is a male potency enhancer; that the latex of the ojé tree (Ficus insipida) is an emetic; and that a drink or poultice made from jergón sacha (Dracontium loretense) can be used to treat snakebite.

Several compendia of such lore have been published — for example, by the prestigious Instituto de Investigaciónes de la Amazonía Peruana — containing scores of plant descriptions, which organize plant knowledge widely distributed among ribereños. While mestizo shamans claim to have learned the uses and administration of their medicinal plants from the plant spirits themselves, it is also true that their uses of the plants are, in most cases, consistent with widespread folk knowledge about the plants.

My teacher doña María Tuesta, for example, was familiar with hundreds of plants, their indication, their preparation, and their application. Walking with her in the jungle was like walking with a plant encyclopedia. She was constantly pointing to the plants by name, giving their uses and their various methods of preparation and application. This knowledge came almost entirely from her own experience — that is, she said, from what the plants themselves had taught her — and from studying with other plant healers.

Doña María was, for all practical purposes, illiterate; for example, she was unable to read a menu at a restaurant in Iquitos. I spent an afternoon with her going page by page through the 105 plants described in the text Plantas medicinales de uso popular en la Amazonía Peruana. She could begin to sound out the popular names of plants in the text until she could match the name with the plant illustrated on the same page, and then complete the name of the plant from memory. Where the name listed in the text was unfamiliar to her, she had difficulty sounding it out. But once she had identified the plant, primarily from the illustration, she would give me a lengthy discourse on its qualities, preparation, and medicinal uses.

There were two striking features of this exercise. First, doña María knew every plant in the book. Second, the descriptions she gave of the medicinal uses of the plant largely matched the descriptions given in the book, which she could not read. Thus, despite the visionary sources of her knowledge, her use of plant medicines was generally consistent with popular plant medicine as practiced throughout the mestizo community.

Consistent with her perception of herself as open-handed with her knowledge, doña María was a vociferous proselytizer for the traditional uses of medicinal plants. In July, 1997, for example, she was invited to speak at a forum on the sexual and reproductive rights of women under the auspices of the Red Nacional de Promoción de la Mujer, the National Network for the Advancement of Women, held at the Universidad Nacional Amazonía Peruana in Iquitos, to address the birthing and care of children. She was one of six women invited to speak to an audience consisting mostly of young mothers.

María had worked not only as a healer but also as a comadrona, midwife, and she demonstrated basic natal care, including how to bathe a baby properly, and, of course, the use of plant medicines — in particular, cordoncillo, the shoestring pepper (Piper aduncum), traditionally used as a tea and as a vaginal wash after birth, in order to flush out excess blood.

In November 1991, having heard about it from a friend, doña María signed up for a course, offered by the Associación de Médicos de Naturismo Práctico Tradicional de Loreto, intended to be a curso de actualización y nivelación de médicina tradicional, a refresher and overview of traditional medicine. María took the course in order to gain credentials for her healing, and in the hope that she would learn new things helpful to her work. “This is what I do,” she said, “and I wanted to learn more.” The course was free, met twice a week for two hours in the evening, and lasted for two years, until October 1993.

The course, it turned out, was significantly below María’s level of knowledge. Other students, she said, would sit quietly and listen; but she — and this is eminently consistent with her personality — would actively tell what she knew about plant use and preparation, staying on in the course in order to help the other students learn. The teachers, in fact, actively encouraged her participation, she told me, saying that she should be the one teaching the course, because of her knowledge of traditional medicine.

The key to healing with plants, according to doña María, is not only to know which plant can heal which conditions but also to understand the proper way to prepare the plants for use. After a month of trying to teach me plant identification, giving me the names and uses of more plants than I could possibly remember, she said to me, “We have all these plants here, cures for all sorts of diseases; now that you have learned about them, you must learn how to prepare them.” What I needed to learn I would learn, over time, from the plants themselves, she said; the way for me to learn is to “continue on, and all will be shown to you.” This was typical doña María. When I would say I couldn’t learn any more, she would scold me. “Study, study, study,” she would tell me. “Follow, follow, follow.”