"In Colombia, it is estimated that more than one million hectares of native forest have been eliminated as a result of illicit crops, and that for each hectare of coca, four hectares of forest are cut down, almost always by the slash-and-burn method. This deforestation, in turn, causes soil erosion."
Source
Organization of American States, General Secretariat, "The Drug Problem in the Americas," 2013, p. 8.
http://www.oas.org/documents/…
