From a recently published article in Geoforum (March 2013):
Coca plantations are the largest illegal agribusiness in the world, and Colombia is the world’s leading coca producer. Since 1994, the Colombian state, with the aid of the US, has waged a war on drugs based on air fumigation of coca plantations. This article evaluates the social and environmental impacts of this policy. We construct and analyse statistically for the first time a spatial database with social, economic, environmental, coca production and fumigation data for all 1125 municipalities of Colombia for the period 2001–2008. We complement statistical analysis with in situ observations and secondary literature review. We find that even if the questionable government claims that overall extent of coca plantations has been reduced were to be true, still coca activity has been diffused in the territory, with devastating environmental and social consequences. Biodiversity hotspot areas are being deforested, and local populations, especially Afro-Colombian communities, are being displaced from their territories. Our statistical analysis provides quantitative evidence to back up previous claims based on victims’ experience, single case-studies and ethnographic observation. We question the effectiveness of the fumigation policy and suggest that what is actually eradicated by the war on drugs is not coca, but humans and the forest.
The title of the article is "Caught in the middle, Colombia’s war on drugs and its effects on forest and people," and it is by Rincón-Ruiz & Kallis.
The authors explain:
We find that in the municipalities where fumigations increased (black color – Maps 2a and 3a), the extent of land covered by coca area declined in the subsequent period (gray color – Maps 2b and 3b). However there was an increase in the extent of the cultivated area in the municipalities neighboring the areas fumigated (black color – Maps 2b and 3b). Therefore the shrinking of coca production in one part came at the expense of expanding in another. In other words, even if overall coca cultivation were to be decreasing (as the official data claims), it is nonetheless diffusing in the territory.More:
And more:. . . is not coca production alone that causes the deforestation; it is the fumigation that is con- tinuously pushing it to new areas.
Even if fumigations have been reducing the cultivated area, which is questionable, their goal of total eradication is not feasible; illegal groups have easily adapted and responded to fumigation with fast reloca- tion, forest clearance and production anew. While the intention of the fumigation policy may have been to make coca cultivation too costly to maintain, illegal groups have managed to shift the cost to producers and the local people, maintaining the lucrative cocaine trade going on. The costs of this ineffective war on drugs are dis- proportionately distributed along lines of class (income), race and ethnicity. Colombia continues to receive massive amounts of US aid to wage this chemical air war on drugs. The policy implica- tions of our study for Colombia and beyond are clear: any govern- ment that attempts to stamp out coca production through aerial fumigations should think twice about its effectiveness and its side-effects.And a meta-conclusion:
Why does aerial fumigation fail? Here we follow this body of lit- erature which suggests that centrally managed social plans often misfire, when they impose schematic visions that do violence to complex local interdependencies that are not fully understood (Scott, 1998). Norgaard (1994) . . .The full article is here.