Armyworms and the Attack on Zambian Agriculture

Marching in platoons and consuming all in its path, the formidable fall armyworm decimates crops in the Americas and Southern Africa each year. Named for its feeding habits, the armyworm is a one and a half to two-inch caterpillar with the power to create famine and collapse an economy. When the armyworm reaches the peak of its life cycle, its platoon can consume 75 percent of a crop in a period of days or weeks.

In Zambia, one of several South African countries affected by a 2017 armyworm outbreak, the scourge is precipitating a corn shortage that could produce widespread famine and inflation in a country dependent on corn for 90 percent of its food. The issue is considered so serious that soldiers have been deployed across the country with backpacks of pesticides in an attempt to limit the damage. The armyworm invasion of Zambia poses severe economic and environmental challenges, creating conditions ripe for change in climate and agricultural policies.

The fall armyworm is an invasive species brought across the Atlantic on container ships. While pests such as locusts and African armyworms frequently plague the corn crops of Zambia and its neighbors, the fall armyworm is unique in that it is an alien species from outside the local ecosystem. It is both more aggressive and more pesticide-resistant than the African armyworm. The spread of the invasive species is exacerbated by an increase in severe weather patterns in Southern Africa, which create the warm and wet conditions that allow the armyworm to thrive. Some scientists attribute these evolving weather patterns to climate change. Regardless of the cause, there is no doubt that the combination of changing weather patterns and a newly invasive species have precipitated an unusual crisis.

The armyworm invasion of Zambia poses severe economic and environmental challenges, creating conditions ripe for change in climate and agricultural policies.

While designating climate change as the sole cause of the armyworm outbreak would be inaccurate, it is indisputable that warmer conditions and environmental degradation have increased the pernicious nature of the outbreak. Nutrient mining driven by a mining-focused economy has caused irreparable damage to the soil. This damage lowers crop yields, making an armyworm attack all the more dangerous. Soil erosion caused by one of the world’s highest deforestation rates remains another indisputable fact of anthropogenic climate change. This erosion also lowers soil yields. Additionally, the UN estimates that the country will remain imperiled by increasingly severe climate events caused by global warming; these storms create the appropriate weather patterns that allow the armyworm to thrive. The South African region is also facing its worst drought in thirty-five years, which has created a severe corn shortage even before the armyworm outbreak.

The food production and consumption patterns in Zambia make the country particularly vulnerable to the armyworm invasion. More than 85 percent of the population depend on agriculture for their income, while maize, the principal cash crop, consumes more than 65 percent of all land used for agricultural purposes. White corn is the main ingredient in nsima or pap, a starchy porridge which serves as the main meal for millions in Zambia and is considered a staple food. White corn shortages could cause both famine and serious inflation, triggering economic crisis, largely because the preferred form of corn in Zambia is grown only in southern Africa, the US, and Mexico. Corn shortages in southern Africa could increase those countries’ dependence on crops in the Americas. Since the prices of imports are higher than locally grown crops, the low-yield years in the Americas can further drive up corn prices and heighten the strain of the shortage in Zambia.

The armyworm invasion has created a cascading series of economic disasters that could imperil the Zambian economy. In Zambia, the corn prices drive inflation, and miners’ unions coordinate their wage demands with inflation. Increased inflation caused by the armyworm-instigated corn shortage has thus led to increased wage demands from miners’ unions. When mining companies fail to meet union demands, strikes erupt and reduce output. Because Zambia is the second largest miner of copper in Africa and copper mining drives the economy, the lowered output has the potential to cause untold damage to the country’s GDP and create even more upward pressure on inflation. Without the added effects of miners’ strikes, corn prices in Zambia are already 50 percent above their five-year average. The country is experiencing a deficit of 5 million tons of corn compared with the usual annual average surplus of 3 million tons.

The complex nature of the crisis necessitates a change in the environmental and agricultural policies of the country. Eliminating food insecurity and developing sustainable farming practices should prevent future armyworm outbreaks from devastating the people and the economy. But how might these policies develop? Shifting away from monoculture is one plausible solution.

Monoculture is defined as the consistent cultivation or growth of a single crop. In Zambia, maize crops are the primary cash crop and primary food source for the majority of the country. Crops such as millet and cassava are more drought tolerant, less susceptible to armyworms, and hold more nutrients than white corn; diversifying to include those crops would ensure that corn is not the country’s only main food source. This, in turn, would ensure that the armyworm becomes less of a threat to the food source and economy. Not only does shifting away from monoculture prevent food insecurity, crop rotation and diversity allow the soil to restore its nutrients, reducing the effects of man-made climate change. Additionally, producing crops that can survive the armyworm attack would reduce the use of pesticides that contaminate the water and surrounding ecological environment.

Government support of maize remains one of the primary obstacles to a shift away from monoculture. The government frequently intervenes to support and subsidize maize crops because it is a politically popular decision; the public responds positively to efforts to create reasonable prices for a primary food source. The government must move beyond the political appeal of maize subsidies, and this shift has yet to occur because there has been little to no incentive. The severity of 2017’s armyworm crisis may be the necessary catalyst to shift government action and allow the general public to recognize the dangers of dependence on maize.

The combination of food insecurity, climate change, and economic risk have created the appropriate impetus to shift Zambian farming practices to a more sustainable model. The future of increased severe weather patterns and global warming, as well as the constant movement of alien species across the globe, ensure that the country will one day face a similar, if not more severe, crisis. Addressing the causes of this crisis with preventative methods such as crop diversification will reduce the risk of severe famine and economic crisis in the future.