Agricultural Settlement and Land Use in Mountains - Mountain Geography: Physical and Human Dimensions - page 558

thought to counteract intestinal parasites. Although rare in the Americas and Europe, it
may well be the world's most popular stimulant. Highlanders in Africa cultivate coffee,
tea, tobacco, cacao, and cayenne pepper ( Capsicum frutescens ), while their Andean
counterparts raise specialty tubers and vegetables.
Farmers usually consume a small portion of each cash crop locally. They transport
the rest for sale in lucrative lowland markets. When roads permit, hired trucks transport
the crop. Otherwise, animals and humans bear the loads. The considerable effort is
worthwhile because cash crops offer a higher value to weight ratio. A kilogram (2.2 lb)
of chili peppers or raw opium greatly outearns an equivalent weight of corn or potatoes.
Most cash crops last longer and can withstand the heavy compression and pounding
that accompany transport. They thrive in nutrient-deficient soils and are in great de-
mand throughout the world.
Some cash crops carry a tainted reputation. The opium poppy ( Papaver somniferum )
is grown and consumed in many mountain regions of Asia (Fig. 11.11). However, most
of the raw opium is sold to nonfarmers for processing into heroin bound for internation-
al markets. Afghanistan produces 85 percent of the world's opium (UNODC 2010). The
rest originates in Southeast Asia's Golden Triangle, where the frontiers of Myanmar,
Cambodia, and Thailand meet, although recently the poppy has also appeared in Co-
lombia and California's Sierra Nevada. The South American coca plant ( Erythroxylum
coca ) has been chewed since Incan times, but today finds its way into urban markets
around the world as refined cocaine. This alkaloid was first isolated and purified in the
mid-1800s, and is an important ingredient in medicines, drugs, poisons, and as a flavor-
ing in cola drinks. Until 1906, cocaine alkaloids were not separated from the flavoring
added to cola drinks in the United States. Since 1995, the global production of coca
leaves has dropped due to government eradication efforts, especially in mature Andean
fields. Though total planted coca acreage remains stable, the newer fields are pushed
into more remote and less productive sites toward and into the Amazon. Peru is the ma-
jor producer of illicit drug crops, followed by Bolivia, Ecuador, and Colombia.