Armyworms May Invade South Africa Sugar Fields After Corn

An outbreak of fall armyworms that has attacked corn plants in South Africa may spread to sugarcane in the KwaZulu-Natal province, where a warm climate would help the pest survive through the year, the Agricultural Research Council said.

The alien pest, confirmed in South Africa this month, has already spread to all nine provinces including eastern KwaZulu-Natal, where the bulk of cane is grown in the nation. There aren’t yet any reports of infestations, Roger Price, a manager at the Pretoria-based ARC, said in an e-mailed reply to questions on Thursday.

“We are very concerned that fall armyworms will get into the sugarcane along the KwaZulu-Natal coast, where it could persist in the warmer climatic conditions,” he said. “My personal view is that the vast bulk of the commercial maize crop has not been damaged and that national food security is not currently at risk.”

The armyworms, which arrived in west Africa from the Americas early in 2016, spread south through Zambia and Zimbabwe before arriving in Africa’s biggest producer of corn, the region’s staple food. There are reports of the pest in Greyton, KwaZulu-Natal, about 70 kilometers (44 miles) north east of the coastal area where sugarcane is grown, Price said.

Temperatures along the KwaZulu-Natal coastline are generally higher than South Africa’s inland areas because of the warm waters of the Indian ocean, providing a more conducive climate for the fall armyworm, which comes from the tropics in the Americas.

It’s difficult to predict what impact an outbreak in KwaZulu-Natal’s cane fields could have, Carolyn Baker, director of the South African Sugarcane Research Institute, said in reply to e-mailed questions.

“We are worried but are somewhat comforted by the fact that the Department of Agriculture, Forestry and Fisheries has circulated a series of responses that can be applied in the event that the armyworm is detected,” she said. “We are taking the lead from the department at this stage.”