Northern Peru runs from the coastal desert around Trujillo, Chiclayo and Piura through dry forest and mountains into the Amazon. Few regions in the world have such a rich medicinal flora. The Peruvian anthropologist Lupe Camino called the north part of the 'health axis' of the Andes, an area from southern Ecuador to northern Bolivia where healers have long gathered and traded plants.
The tradition is old. Archaeologists have found remains of the San Pedro cactus at sites that are thousands of years old. The Moche, who lived on this coast between about 100 and 800, depicted healers on their pottery, as well as the San Pedro and the seeds of cabalonga and of ishpingo. Remains of such plants have been found in the tomb of the Lord of Sipán, a Moche ruler.
Moche pottery also shows a mysterious, comma-shaped fruit with a large calyx, which researchers call ulluchu. It hangs from the belts of warriors and messengers and floats around priests and sacrificial scenes, and real fruits have been found in graves. Nobody knows for certain which plant it is. Bussmann and Sharon think of a Guarea, an Amazonian tree whose seeds contain poisonous alkaloids, and suspect that the Moche used them in sacrifices and perhaps as a snuff. That is a hypothesis not yet confirmed by chemical analysis. The name is uncertain too: the archaeologist Rafael Larco Hoyle used it in the 1930s, but it does not appear in the dictionaries of Mochica.
After the Spanish conquest, Indigenous medicine blended with Catholicism and with Spanish ideas about illness. In the 1780s Bishop Baltasar Martínez Compañón of Trujillo had everything in his diocese described and painted, including the useful plants. According to the botanist Rainer Bussmann and the anthropologist Douglas Sharon, about 40 per cent of those plants are still sold in the coastal markets. A third is now used only in the Amazon, and the rest fell out of use. At the same time many new plants were added. In their view, healers in Peru could experiment more freely than in Ecuador, where traditional medicine was persecuted for a long time.