The outbreak of the African Armyworm (AAW) in Botswana has had significant and varied impacts on both crop production and grassland ecosystems, directly threatening food security and livestock livelihoods
GAZETTE REPORTER
A looming shortage of food is threatening Botswana as a widespread infestation of the African armyworm (AAW) wreaks havoc on the country’s staple maize crop, raising alarm over national food security.
This is according to an assessment report prepared by the Ministry of Agriculture in collaboration with Food and Agriculture Organisation of the United Nations.
“The African armyworm (AAW) outbreak in Botswana has had significant and varied impacts on both crop production and grassland ecosystems, directly threatening food security and livestock livelihoods.
Aggressive infestation
“Crop losses have been substantial, with 2,044.15 hectares (ha) of maize – Botswana’s staple crop – affected across 342 farmers,” the report says.
It notes that recent field assessments have revealed extensive crop damage across multiple farming regions, with experts confirming that the anticipated African armyworm outbreak has been overshadowed by a more aggressive infestation of the autumn armyworm.
The invasive pest has caused severe damage to maize plants, particularly targeting the whorl and leaf areas which are key parts of the crop’s early development.
Visible leaf damage
The assessment reveals that low-level damage is the most prevalent, affecting 43% of the maize fields surveyed. “This suggests widespread but relatively mild infestation, where visible leaf damage exists, but plant vigour and yield potential may not yet be significantly compromised,” the report says.
It notes that moderate damage was reported in 24% of the cases. “This indicates areas where the infestation is more established, with more evident feeding on whorls and leaves, potentially impacting plant development and requiring intervention to prevent further spread,” the report says.
High levels of damage were noted in 14% of the surveyed fields. “These fields are likely experiencing severe feeding that may result in significant yield loss if control measures are not promptly applied,” says the report.
The presence of high-damage zones is a clear warning sign that the pest is actively impacting maize production and poses a threat to food security, if left unmanaged.
Livestock fodder
According to the report the Goodhope/Mmathethe, Moshupa, and Mogoditshane/Thamaga districts reported severe AAW damage to maize crops, with over 50% of fields showing high infestation levels.
The North West and Charleshill districts also faced significant crop losses, exacerbated by delayed control measures due to fuel shortages. The North West, Boteti, and Moshupa experienced high pasture damage, threatening livestock fodder availability.
Only 4.2% of affected grasslands were controlled. The outbreak of the African Armyworm in Botswana has had significant and varied impacts on both crop production and grassland ecosystems, directly threatening food security and livestock livelihoods.
Crop losses have been substantial, with 2,044.15 hectares (ha) of maize – Botswana’s staple crop – affected across 342 farmers.
Vegetative stage
While 85% of infested cropland
(1,736.72 ha) has been controlled, delayed interventions in districts like North West (Chanoga) and Moshupa resulted in partial yield losses, exacerbating risks to household food supplies.
AAW primarily targets crops, especially maize, sorghum, and vegetables, causing direct yield losses of 20–50% in staple foods and posing a significant risk to food security.
The report says at the time of the crop scouting, the majority of the maize crops were at the vegetative stage (58%), which is highly susceptible to the worm that feeds voraciously on leaves and stems, stunting plant development.
Mixed farming systems
“AAW becomes more active as crops grow, especially in mixed farming systems where larvae move from pastures to fields, compounding defoliation,” says the report.
It notes that the 2025 outbreak of the African Armyworm in Botswana has underscored the fragility of agricultural and pastoral systems already weakened by recurrent drought, climate variability, and ongoing pest pressures.
“While national response efforts – led by the Ministry of Lands and Agriculture with support from Food and Agriculture Organisation (FAO) – successfully curtailed 85% of the AAW-infested cropland, the low treatment coverage in grasslands (only 4.2%) has left pastoral communities acutely exposed,” says the report.