Huachuma, a history of San Pedro in the Andes

The earliest physical evidence comes from Guitarrero Cave in the Callejón de Huaylas, in the Áncash region of Peru. Remains of the cactus there are dated to around 8,600 years before the present, a time of hunter-gatherers. A review by Giorgio Samorini (2019) describes a high concentration of Trichocereus pollen from the oldest phase of human occupation, together with fragments of cactus, which suggests the plant was carried into the cave on purpose (Guitarrero Cave).

What those people did with it is not known. Pollen and fragments show that the plant was there and was handled. They do not show that it was eaten for its effects, and careful writers keep those two claims apart.

The oldest known images of San Pedro date from the first millennium before our era. At Chavín de Huántar, a temple complex in the Callejón de Conchucos, the cactus appears in the carved stone art. Ceramics of the Cupisnique culture of the Jequetepeque valley, contemporary with Chavín, show the cactus as well.

By that period the use was widespread. The 2022 declaration lists traces of San Pedro at the Formative sites of Las Haldas, in Casma province, and Garagay, in the Rímac valley near present-day Lima.

Later cultures kept the plant in their imagery. The cactus appears in Paracas textiles and in the religious iconography of Nazca ceramics and textiles, both from the Ica region on the south coast. On the north coast, Moche ceramics (around AD 100 to 800) and later Chimú ceramics show the cactus being used in rituals by mythical figures and by officiants, with a striking number of women among them. Bussmann and Sharon add that remains of some of the ritual plants shown on Moche ceramics were found in burials of the Moche elite.

After the Spanish conquest the cactus became a target of the campaigns against "idolatry". The 2022 declaration summarises what the colonial record shows:

• Jesuit priests recorded that the indigenous nobility drank a cactus called achuma, grown in warm valleys, in rituals that had been folded into the cult of Saint James (Santiago), who in turn had taken over attributes of the Andean thunder god Illapa.
• Eighteenth-century court records from the north coast, from places as far apart as Cajatambo, Ferreñafe and Cajamarca, describe ritual specialists who used the cactus and were prosecuted as sorcerers and heretics.
• Under that pressure the practice moved out of public view and carried on in secret.

The Christian name San Pedro dates from this period. The declaration links it to Saint Peter, the holder of the keys of heaven: the cactus as the key to the spiritual world.

What survived is a ritual tradition known in Spanish as curanderismo, centred on the coast and highlands of Piura, Lambayeque, La Libertad, Tumbes and parts of Cajamarca and Áncash. The first academic descriptions came from the studies of traditional practice by Hermilio Valdizán, from 1911 onwards; in the second half of the 20th century anthropologists such as Douglas Sharon and Marlene Dobkin de Ríos documented it in detail.

The declaration describes the ritual as follows. A maestro curandero leads the ceremony, helped by an assistant called the alzador. The centre of the ceremony is the mesa: a woven cloth on which objects called artes are laid out like a map of the cosmos, in two halves with different roles. The objects include old swords, staffs, rattles, stones, shells, archaeological pieces and images of Catholic saints. The drink is offered to the four directions, to the spirits of mountains and lagoons, to the saints and to the ancestors, and the session is accompanied by songs, rattles, tobacco smoke and sprinkled agua florida.

Collection and cooking are ritual acts too. Stems are cut at dusk around full moon, after prayers and offerings to the plant, and the bark is boiled for many hours under a watchful vigil. Practitioners prefer nearly spineless, yellowish-green plants with seven or eight ribs, which they call "female". The spinier, bluish "San Pedro cimarrón", called "male", is associated with maleros, specialists who aim to cause harm; the declaration explicitly excludes them from its protection.

In this tradition the cactus is not taken for its own sake. It is understood as a way of seeing into the spiritual world, open only under the guidance of the curandero. The state of mind it produces is called huanto, from the Quechua wantuq, "raised up".

On 17 November 2022 the Peruvian Ministry of Culture published Vice-Ministerial Resolution 000252-2022-VMPCIC/MC in the official journal El Peruano. It declares "the knowledge, wisdom and traditional uses of the San Pedro cactus in the practices of curanderismo in northern Peru" Cultural Heritage of the Nation. The file was prepared by the culture directorate of La Libertad together with those of Tumbes, Piura, Lambayeque, Cajamarca, Amazonas and Áncash.

The declaration draws a clear line between this ritual use and recreational use. It also notes that the tradition has entered the market and the media, and that in cities and in the tourist trade the relationship between officiant and participant now works differently and is more oriented towards profit. The heritage status protects a cultural practice; it says nothing about the drug law, which is covered on the legal page.

The first scientific study of cimora, as the cactus is also called in northern Peru, dates from the 1940s, according to Bussmann and Sharon. Outside South America the cactus is now mainly sold as an ornamental plant. If you want to know what the plant itself is, read what San Pedro is; for what mescaline does, see effects and duration.