Coca
Coca encompasses cultivated varieties of the shrub Erythroxylum coca and Erythroxylum novogranatense in the family Erythroxylaceae, native to the Andean slopes of western South America including Peru, Bolivia, and Colombia.[1] These plants produce elliptic leaves containing a mixture of tropane alkaloids, with cocaine comprising 0.42% to 1.02% of dry weight on average.[2] For over four millennia, indigenous Andean communities have masticated the leaves, often alkalized with lime, to suppress appetite, alleviate altitude sickness, and enhance physical endurance, deriving benefits from both the alkaloids and nutritive compounds like vitamins and minerals.[3][4] The coca shrub thrives in subtropical valleys at elevations of 500 to 2,000 meters, featuring small white flowers and red berries, with leaves harvested multiple times annually after a two-year maturation period.[1] Beyond traditional mastication and infusion as tea, the leaves serve nutritional roles, providing calories, proteins, and essential micronutrients in regions with limited food access.[3] The isolation of cocaine hydrochloride in 1860 by Albert Niemann enabled its initial pharmaceutical applications as a stimulant and anesthetic, though subsequent recognition of dependency risks shifted perceptions toward prohibition.[1] International treaties classify coca leaves as a narcotic precursor due to cocaine extraction potential, fueling eradication efforts that conflict with Andean cultural practices where leaf use evidences no progression to purified cocaine abuse, attributable to synergistic alkaloids mitigating addiction pathways.[2][1] Cultivation persists legally in Bolivia and Peru for domestic consumption, underscoring tensions between empirical evidence of moderate leaf benefits—such as improved oxygenation and reduced fatigue in laborers—and global drug control paradigms prioritizing supply suppression over differentiated regulation.[5][6]Botanical Characteristics
Description and Morphology
Coca comprises evergreen shrubs of the genus Erythroxylum, primarily E. coca and E. novogranatense, reaching heights of 1 to 2.5 meters with erect, smooth, branched stems forming a bushy habit.[7][8][4] The leaves are alternate and simple, thin, elliptic-oblong to narrowly obovate-elliptic in shape, measuring 2 to 7 cm long with a blunt apex and pointed base; they appear light green, oval to lance-shaped, typically 6 cm in length and 3 cm across.[7][8] Flowers emerge in small clusters at leaf axils, featuring five white to yellowish-white petals and measuring a few millimeters across.[7][8] The fruit develops as an oval, glossy red drupe, oblong and 7 to 10 mm long when ripe, enclosing thin pulp around a single seed.[7][8][4]Species and Varieties
The cultivated coca plants belong to two primary species within the genus Erythroxylum of the family Erythroxylaceae: Erythroxylum coca Lam. and Erythroxylum novogranatense (Morris) Neyra.[1][9] These species encompass four main varieties domesticated through human selection over millennia, differing in morphology, alkaloid profiles, and adaptation to specific environments.[10] Erythroxylum coca includes var. coca, commonly known as Huánuco or Bolivian coca, which features larger leaves and is primarily cultivated in the moist Andean highlands of Peru and Bolivia at elevations of 500 to 2,000 meters.[11] This variety typically contains 0.23% to 0.96% cocaine by dry leaf weight.[12] The second variety, E. coca var. ipadu Plowman, or Amazonian coca, is a smaller, shrubby form adapted to humid lowland forests below 500 meters, with reduced stature and higher tolerance to shade and flooding.[13] Erythroxylum novogranatense comprises var. novogranatense, the Colombian coca, suited to drier inter-Andean valleys and capable of growth in semi-arid conditions with cocaine contents ranging from 0.5% to 1.0%.[14] The var. truxillense (Rusby) Neyra, or Truxillo coca, originates from Peru's coastal valleys and exhibits enhanced drought resistance, often yielding leaves with elevated tropane alkaloid levels including up to 0.36% cocaine in some samples.[15] These varieties reflect distinct evolutionary domestication events, with E. novogranatense showing genetic adaptations for arid habitats compared to the more mesic preferences of E. coca.[10]| Species | Variety | Common Name | Primary Habitat Characteristics |
|---|---|---|---|
| E. coca | var. coca | Huánuco/Bolivian | Moist Andean highlands, 500–2,000 m elevation |
| E. coca | var. ipadu | Amazonian | Humid lowlands, shade-tolerant, flood-resistant |
| E. novogranatense | var. novogranatense | Colombian | Drier inter-Andean valleys, semi-arid adaptable |
| E. novogranatense | var. truxillense | Truxillo | Coastal valleys, high drought tolerance |