Just one road connects Tumaco, the second-busiest port on Colombia’s Pacific coast, to the rest of the country. Beyond its verges are fields of coca bushes, many of them cultivated by poor people. Yuley Alexandra Ruano’s crop grows behind a beauty parlour she owns on a patch of land she does not. It is fringed by yucca, plantains and a rotting cacao tree. She and her neighbours have signed up to the government’s “comprehensive programme for illicit crop substitution” (PNIS), whose aim is to replace the coca with a profitable legal crop. But bureaucracy moves slowly. Ms Ruano has yet to see new seeds or the money promised by the government to help with the switch.

From her salon in the department of Nariño, she can see that the government is pursuing with more energy the other part of its anti-coca strategy, forced eradication. Every day a Black Hawk helicopter passes, bearing police to a jungle camp in Alto Mira y Frontera (see map). Their mission is to kill the bushes, by uprooting them or by spraying them with herbicide. The government wants to eradicate by force 65,000 hectares (160,000 acres) of coca this year.