Coca belongs to the family of Erythroxylon, of which from 250 to 300 varieties are known and of these nearly 200 are found in Latin America. The plant is mostly native to the moist eastern slopes of the Andes and is cultivated primarily in Columbia, Peru, and Bolivia. There are two varieties found in Bolivia. Before the Spanish colonial times, Erythroxylon cocalam, also called Coca Huanuco, was already cultivated on terraces of the Yungas region between 500 and 2000 meters elevation (1500 to 6500 feet). In the lower lying, hotter Chapare region, the variety Erythroxylon novogratenense was introduced during the middle of the 20th century, having been imported from Columbia. In Bolivia, the coca bush achieves a height from half a meter [18 inches] (Yungas) to 2.5 meters [8 feet] (Chapare). The small leaves of the Paceña from Yungas is used for the traditional consumption, while the Chapareña as a result of its bitter taste is not so good for chewing and is only used by the poorest of the Bolivians. The reason is the higher alkaloid contents of the Erythroxylon novogratenense. Just as with coffee, one can distinguish the high quality coca from higher elevations from the less expensive coca from lower regions.
Since coca does not demand much of the soil, the climate is most important for its cultivation. The plant requires sun and sufficient water. Given an appropriate climate, four harvests per year are possible. The leaves are dried and then can be used immediately. While chewing it, one leaf after the other is put into the mouth, until a "coca wad" fills out the cheek. The coca wads are mixed with the saliva and an added alkaline substance (usually ashes of any various plants) to extract its contents so the body can absorb these. A study done at Harvard University in 1975 showed the results that 100 grams of coca leaves supply the daily requirements for calcium, phosphorus, iron, along with the vitamins A, B6, B12, C, and E. Aside from this nutritional value, the use of coca also anesthetizes and increases performance. This leads to a reduction of the sensations of hunger and thirst, and desensitizes against pain or cold. At the same time, the oxygen absorption is increased, the circulatory system is stimulated, which finally also relieves tiredness, similar to drinking coffee. With the use of coca leaves, there is no sense of inebriation. There is only a slight anesthetic effect inside the mouth, especially when using the alkaline catalyst. This is because of the anesthetic effect of cocaine, one of fourteen alkaloids contained in the leaf. Because of its physiological attributes, one can even regard coca as a basic food for the rural inhabitants of the Andes. It complements their poor carbohydrate diet with important vitamins and trace elements. At the same time, it is used as a medicine against altitude sickness, gastrointestinal diseases, and cardio-vascular illnesses.
The significance of coca for the indigenous population of Bolivia does not end with the above mentioned qualities. The leaves also fulfill important societal and religious functions. The social function of coca begins with the mutual chewing, or when coca leaves are exchanged as a greeting. In general, the leaves are an important monetary unit for barter. For the so-called Ayni, when neighbors assist each other, for example to help with a harvest, the coca leaves must not be missing. In this case, they fulfill an important aspect of reciprocity, the central principle within the Cosmovisión Andina, the Andean philosophy and religious ideology.
Various myths and legends surround coca, such as the idea that "Mama Coca" was a woman who transformed herself into this plant to feed her children. Such myths contribute to giving the coca plant magical, religious qualities. Thus, coca leaves are also used in rituals as an offering, which serve to please the gods and make them merciful, as in the yearly sacrificial ritual for Pachamama, Mother Earth. But they are also used by shamans and wise men, so-called Yatiris or Curanderos, as a method of communication, to get in touch with supernatural forces. By throwing coca leaves onto a cloth and then interpreting through the form, color, structure, and constellation with other leaves, the Yatiri uses the magical qualities of the leaves and reads them, as one would read a book of truth.
This is only an attempt to summarize the complex meaning of the coca plants for the people of the Andes in a compact form. In any case, it becomes clear that at least in our "European culture" no plant exists which has a comparable significance.