Liberia has declared a state of emergency in agricultural areas decimated by swarms of caterpillars. The government in Monrovia is asking for international assistance to turn back the pests that are destroying crops and polluting drinking water.
An infestation that began in Bong County has now spread to lower Lofa County and parts of Gbarpolu County along Liberia's borders with Guinea and Sierra Leone.
"They are devouring forest trees, which we suspect were their host plants and from there they have now started to attack crop species," said Qwelibo Subah, director general of Liberia's Central Agricultural Research Institute.
The black, hairy caterpillars are about three centimeters long and are spreading quickly as adult moths can fly great distances at night. Subah says more than 130,000 people are now homeless in the affected areas where water is contaminated with caterpillar feces.
"We are working on a huge program for assistance wherein we can be able to tackle the problem at the source while containing it on the ground," he said. "Repairing hand pumps that are broken, constructing new ones, chlorination of wells, a whole range of things because the health aspect we can not neglect."
Subah says they are already spraying pesticide, but their small hand-sprayers can not reach the forest canopy, in some places as high as eight meters. Areas that have been hand-sprayed have quickly been re-infested. So the government is asking for help to contain the damage.
Aerial spraying may be the only way to put down the swarms. But U.N. Food and Agriculture Organization entomologist Winfred Hammond wants to know more about the pest they are dealing with before risking further contamination with aerial spraying of pesticides.
"We are a bit reluctant about that approach because it is already a risky situation, and we don't want to make it worse," he said. "We don't understand the problem fully, and that is why we want to get our people out as quickly as possible."
Hammond and a team of insect consultants will inspect crop damage and polluted water sources in the border areas this weekend. That survey will eventually extend into Sierra Leone and Guinea to prevent what Hammond says could be a regional catastrophe.
The areas affected are some of Liberia's richest agricultural zones where much of the nation's cassava, plantains, bananas, and potatoes are grown. Environmentalist Ben Donnie says the infestation is sure to worsen Liberia's already tenuous supply of food.
"People who are producing all of this sugar cane from which people brew cane juice that market may come down," he said. "All the beans and the peanuts. You know how many peanuts we consume in this country. Then don't talk about rice. We can't live without rice. We could live without cane juice. But we can not live without rice. And Bong County and Lofa County are known to produce the highest amount of rice in this country."
With streams and wells in more than 50 villages already contaminated, Donnie says the infestation is hardest on children and the elderly who must now walk long distances to find safe drinking water.
"With your food destroyed and you have to travel over four miles to get water to drink, you can agree with me that you don't have to be an environmentalist to know that it is a serious problem," he said.
West Africa's last large outbreak of army worms occurred in Ghana in 2006. This infestation is thought to be Liberia's worst in more than 30 years.