The US and UN are negotiating with Columbia to get agreement on using the Fusarium oxysporum fungus against coca plantations there. Chemical herbicides are already in widespread use, but the fungus is different because it spreads by itself, and it remains in the soil for many years.
Tests in Hawaiian greenhouses showed that the fungus did not affect 50 related plants. Yet there are thousands of plant species in Colombia, and Fusarium is known to rapidly mutate and affect multiple plant species.

The Colombian government is said to be considering the agreement. Meanwhile, the US Congress is considering putting an extra $1.6 billion into Colombia's coca and poppy eradication projects.