Armyworms threaten food security in SADC
A plague of armyworms is threatening food security in southern Africa following invasion of crop fields in countries like Botswana, Namibia, Zambia and Zimbabwe.
The African armyworm (Spodoptera exempta), a very deleterious migratory pest, is known for its appetite for grasses and cereals and can wreak havoc on crops in a matter of days, if left unchecked.
The outbreak has caused panic in the region, with rising fear that the plague might lead to poor yields this season.
The moth larvae, which derive their name from their feeding habits, march in large numbers across grasslands and grain fields ‑ eating everything on their path. Their diet consists mainly of grasses and early stages of cereal crops like maize, rice, wheat, millet, and sorghum.
Authorities in Botswana, Zimbabwe and northern regions of Namibia are frantically trying to contain the outbreak.
In Botswana, armyworms have invaded most parts of the country except the Kgalagadi region, the Ministry of Agriculture has confirmed.
It remains a mystery why the Kgalagadi region survived the plague.
Though damage could not be quantified yet, Botswana’s Ministry of Agriculture spokesperson, Moreri Moesi, said surveillance on the pest is still on-going.
Moesi said the main concern presently is the spread of the armyworms than the damage caused thus far.
“For now our main focus is to contain the worm as quickly as possible and then focus on the damage caused later,” he said.
The worm is reportedly common after a dry period. Moesi has urged farmers to weed their fields, as the armyworms seem to be attracted to grassy fields.
The government further advised farmers to resort to traditional measures to control the pest, like digging 30-centimetre deep trenches around their fields.
Reports from Zimbabwe indicate that the armyworm outbreak threatens to worsen food security in the country, where close to 1.6 million people already face food shortages.
According to the Plant Protection Research Institute, the crop-eating caterpillar could spread further as “moist winds blowing into Zimbabwe from the north may bring more moths and trigger fresh outbreaks of the pest”.
Godfrey Chikwenhere, who heads the institute and is the government’s chief Entomologist, is quoted as saying the rapid spread of armyworm moths has made it difficult to contain the outbreak.
“They originate in countries such as Zambia, Uganda and even Tanzania and are blown into the country when strong, moist winds bring rain.
More rainfall brings more moths and, ultimately, fresh outbreaks.”
The outbreak has so far hit five of the country’s eight farming provinces. It is reported to have destroyed hundreds of hectares of the staple maize crop in Mashonaland Central, Mashonaland West and Manicaland, the country’s top food-producing provinces.
Midlands and Matabeleland North provinces have also been affected.
Chikwenhere says the government has enough carbaryl, the chemical used to contain the pest, contrary to a senior official in the Ministry of Agriculture, who requested anonymity, who says there is a shortage of the pesticide.
In northern Namibia, the outbreak was first reported in the Omusati region and has since spread to other regions, including Oshana and Oshikoto.
The pest, commonly known as ‘okalombo’ in the area is said to have caused significant damage to crop and grazing in Oshana and Omusati.
Like in Botswana, the Omusati Regional Council has been encouraging affected subsistence farmers to resort to traditional measures of fending off the armyworm invasion by digging trenches around the fields rather than relying on the pesticides.
Meanwhile, Omusati Governor Sophia Shaningwa has raised concern over the use of pesticides in the fields, fearing chemical side effects.
“This is not the first time we are getting attacked by armyworms.
Our people have always relied on the traditional method to fight them,” she said.
According to Shaningwa, her office has consulted the local veterinarian who advised them to use traditional methods, since they are safe for both humans and livestock.
“The veterinarian said the Ministry of Agriculture, Water and Forestry should not use pesticides, because they are harmful for livestock.
“Even if you treat the mahangu fields only, you can never guarantee that animals would not enter the fields and feed on the treated crops.
“Our people should just dig trenches around their mahangu (millet) fields so that the armyworms can fall in,” Shaningwa said in a local daily, New Era, recently.
“The armyworms are many and they eat 24 hours a day. If they get to a place they completely clean the area.
“We are just praying that God will send us rain and once it rains all the worms will be swept away to the oshanas where they will eventually die,” said Shaningwa.
Her counterpart, Clemence Kashuupulwa for Oshana, has also appealed to farmers in his region not to wait for pest control officials from Ministry of Agriculture, Water and Forestry but rather start digging trenches.
However, Kashuupulwa could not ascertain the extent of the invasion and damages, but said hundreds of farmers were affected.
He warned that the harvest in the region is not only threatened by the plague, but operators of government tractors who are responsible for ploughing mahangu fields have halted in order to help the Agricultural Extension Officers in spraying the fields.
Zambia recently emerged from the battle against the outbreak of armyworms, which threatened food security in the copper producing nation in December 2012.
The armyworm invasion was severe and unprecedented in the history of the country, the Zambian Government has noted.
Seven provinces except Western, North-Western and Luapula were affected and an estimated 90 000 hectares of maize crop was invaded.
Small-scale farmers, who are beneficiaries of the Farmer Input Support Programme (FISP) and contribute significantly to maize production, were the worst affected.
Experts in that country have said the impact of the pests is particularly remarkable in maize, the staple food in most of Africa.
Their main distribution areas, the experts say, are eastern Africa, namely Kenya, Somalia, Sudan, Tanzania, and Uganda and central and Southern Africa namely Botswana, Malawi, Mozambique, Swaziland, South Africa, Zambia and Zimbabwe.
Populations are also found in West Africa and the Indian Ocean islands.
The armyworm is a migratory pest, which, in eastern and southern Africa, displays a distinct migratory pattern.
The moth apparently starts breeding along the coast of East Africa and Mozambique further south.
A progression of outbreaks then follows two directions: one northerly, from Tanzania to Ethiopia and across into Yemen, and the other to the south towards South Africa.
However, there are indications that initial breeding might also take place in Angola, leading to outbreaks spreading into Zambia and further south into Botswana and Zimbabwe.