The ribere¤os who inhabit the banks of the Amazon's water-ways are mestizos, a people of mixed blood ancestry, commonly Spanish and Indian. They are not jungle natives, but are homesteaders who have chosen to settle beside the river. Living without electricity or plumbing in a fairly remote area, they nevertheless have a few amenities such as kerosene lamps, hunting rifles, and occasionally an outboard motor.
Fishing and subsistence farming are the primary means of livelihood, and the river is the main mode of transportation.
Because the nearest medical doctor can be eight hours or more away by canoe, native plants are an important source of medicines in ribere¤o settlements. Particularly useful species are grown in small gardens next to the house. Although their knowledge of local medicinal flora is not as extensive as that of the forest-dwelling Indians, the ribere¤os are conversant with species useful in treating common ailments.
We climbed the nearly vertical bank on steps dug deep into its hardened side, the water being low now in early spring. The area of our visit had been flooded six months earlier, and a number of the medicinal plants had been washed away. Despite this loss, we found a remarkable collection in the garden.
Our guide was Edgard Vascones, a ribere¤o himself, who had gone to the university in Iquitos. He introduced us to the owner and his family, and explained that we had come all the way from North America to see his garden. Without betraying the slightest hint that this was odd, the ribere¤o welcomed us, deferring to his wife as the expert on the plants they used as medicine. We were accompanied by a few of our own experts.
Included among our number were USDA ethnobotanist Dr. James Duke, Dr. Rosita Arvigo, whose particular expertise is the medicinal flora of Belize, and Dr. Varro Tyler, professor of pharmacognosy at Purdue University. All three are distinguished leaders in their fields, and the opportunity to spend time with them in the field made our visit truly exciting.
Dr. Duke came equipped with a copy of his nobotanical Dictionary, which he co-authored with Rodolfo Vasquez (CRC Press: Boca Raton, 1994). It was an extremely useful resource for the tour (and a valuable reference book for this article).
Our first stop was riverside at a tree botanically identified as Campomanesia lineatifolia, known to the ribere¤os as "palillo." Medicinally, an infusion of the wood chips from this species is used for the treatment of hemoptysis, the spitting of blood from the lungs. Palillo is also considered to have antiemetic properties and is used for skin infections. Beyond its medicinal value, this tree provides berries for food and wood for lumber.
Making our way toward the main garden, we gained a close view of the house. Typical of a ribere¤o home, the structure had a thatched palm roof, was open on three sides and built on stilts to accommodate the seasonal flooding of the Napo. The floorboards of the main platform were made out of planks slatted from the trunk of the palm tree Iriartea deltoidea. Once affixed to the platform structure, the planks are springy to walk on, but extraordinarily resilient and durable.
In the principal garden, Rosita immediately identified two plants used medicinally in Belize, Piper peltatum and Kalanchoe pinnata.
Piper peltatum is called "Santa Mafia" by the ribere¤os. A lowlying species with heart-shaped glossy foliage, this plant has both household and medicinal uses. The leaves not only provide tablecloths and food wrapping material, but are also rubbed on the body to repel ticks and applied directly to swollen sores. A leaf decoction emetic and diuretic properties is used to treat inflammation and fever. In Belize, Piper peltaturn is used to treat in the breasts of nursing mothers.
Familiar to many Americans as an ornamental, and commonly called the "air plant," Kalanchoe pinnata is something of a panacea to the ribere¤os. In Belize, it is called "everlife" and is also widely valued. This plant has dark green leaves that are distinctively scalloped and trimmed in red. An infusion of the crushed leaves is used to treat fever, intestinal upsets, and heartburn. The leaves are also mashed and poulticed for headaches. One unusual formulation is to mix a few drops of the leaf juice with mother's milk for treating earache. Scientifically, we know that the leaves contain malic, citric and isocitric acids, rutin, quercetin, and bryophilline, which is active against gram positive bacteria.
Moving on through the garden we encountered the Amazonian version of stinging nettle (Urera spp. in Amazonia), familiarly known to the ribere¤os as "Ishanga colorado." It is a member of the Urticaceae, as is the North American species Urtica dioica. Described as a counterirritant by Jim Duke, the stinging hairs on the leaves are used to relieve rheumatic and arthritic pain. Numerous other uses of this plant include treatment for chills, fever, malaria, and as a diuretic. It is also used, we were informed, as an aid in disciplining children!
As we turned to explore the garden on the opposite side of the house, Dr. Duke stooped to pull up a "weed" for examination. This happened to be one he frequently mentions in his lectures as a potential "cancer-preventive" -- purslane (Portulaca oleracea). It is an excellent source of the antioxidants vitamin E and beta carotene. The ribere¤os crush the plant and use it for stings, swelling, and fever.
Another surprise between the gardens was Heliotropium indicum, one of the most fascinating and notable plants of our visit. A member of the Borage family, its light purple flower spikes are constantly swarmed by orange and black butterflies. The flowers contain pyrrolizidine alkaloids which are converted into pheromones by the males of this butterfly species. There are numerous folk medicinal uses of the plant as well, including treatment of everything from asthma to warts. Folklorically known as a remedy for cancer, it has been shown to contain the antitumor compound, indicine-N-oxide. Another member of the same genus which grows in the Mediterranean, Heliotropium hirsutissimum, has been analyzed for similar alkaloids.
Manioc, the staple of the ribere¤o diet, and other edible plants were found in the second garden. Among them was Amaranthus spinosus. This common grain, which is high in iron, is frequently served in soup and the ribere¤os know that it is good for anemia. Other medicinal uses are as a whole plant laxative and as a decoction for fevers and swellings.
We found several plants that we had sampled in the meals at our two lodges across the river. Fresh lemongrass (Cymbopogon citratus) was served as a tea at the ACEER, and it was delicious. The tea is used medicinally for stomachache, indigestion, fever, flu, and headaches. One native tribe actually considers the decoction to be a contraceptive. Two close relatives of lemongrass (C. nardus and C. winterianus) are the sources of citronella oil. This versatile essence is used, among other things, to flavor carbonated beverages and in making insect-repellent candles.
The juice of the fruit of cocona (Solanum sessiliflorum) was on the breakfast buffet at Explorama. It is not only a refreshing drink, but also an antiemetic administered after scorpion stings to prevent vomiting.
As we left the garden, the equatorial sun could be seen hanging low, upriver. The silt load of the Napo, which normally colors the tributary an opaque reddish brown, was now obscured by the late afternoon glare. A woman seated on the broad, open-air porch pulled large, exotic-looking fish of several species from bright orange basins and carefully cleaned them. We moved toward our host, shook hands, and took our leave one by one.
The brief visit impressed one with the self-reliance of these people, and their connection to the plants, the land and the river. To be able to pluck a few fresh leaves of plant material to wrap food or prepare an infusion for a child's fever are still necessary skills here in this tropical wilderness. And what an array of plants are available! One day we may glean an important pharmaceutical from a plant that was here all along, in the garden of a barefoot ribere¤o.
Article copyright American Botanical Council.
By Kathy McKeon