The “bora” (eichhornia crassipes), is a species of tropical water hyacinth that has spread like a green carpet over two-thirds of La Mariposa reservoir in Venezuela. The reservoir covers 54 hectares and has a capacity of 8 million liters, which supplies most of the Venezuelan capital. The plant is not toxic, so it does not a pose a threat to the residents who drink the water from the reservoir, according to the Ministry of Environment, which has sent workers with tractors to pull out tons of bora each day.

“But the manual eradication has not eliminated the plant's seeds, which sink to the bottom of the reservoir and which facilitates its rapid reproduction,” Marcial Barrios, of the Venezuelan Ecologist Movement, told Tierramérica.

Furthermore, “the decay of the plants in addition to the waste that comes from neighboring workshops threatens to create pollution that would indeed be harmful to health,” said Barrios.