The area under cassava has increased sharply this year, especially in mountainous areas, after the price of the roots doubled recently compared to last year.
The price traders pay for fresh cassava, which is being harvested now, is VND2,000 a kilogramme, while for dried cassava, it is VND4,800-5,000, as demand for exports skyrockets.
In the central province of Phu Yen, farmers in the mountainous districts of Tay Hoa, Dong Xuan, Son Hoa, Song Hinh are reclaiming uncultivated land and switching from growing other crops like sugarcane, corn, and beans to cassava.
Growing cassava involves low costs and it is a hardy crop that requires little care. But at current prices, a ha can fetch a profit of VND15 million-35 million (US$720-1,680) depending on output, farmers say.
Ma Mua, a farmer in Song Hinh Commune in the district of the same name, said: "My family used to grow cassava on three ha but has now increased it to seven ha."
Tran Thanh Dinh, deputy chairman of the Song Hinh District People’s Committee, said the district had only planned for 3,000-3,500ha of cassava but the area has already increased to 7,000ha and was continuing to rise.
"Farmers are not only switching from other crops but also destroying forests to grow cassava," he said.
Forest rangers have discovered more than 200 instances of destruction of natural forests to grow cassava. More than 66ha of forests have been felled.
Last year areas under cassava totalled more than 496,000ha, 12,000ha less than in 2009, while output was 8.5 million tonnes, according to the Ministry of Agriculture and Rural
However, figures for the next crop are not available yet.
Tran Duc Lam, deputy director of the Yen Bai Province Department of Agriculture and Rural Development, said last year cassava was grown on 13,000ha and this year it was estimated to increase to 25,000ha.
Before farmers decided to take matters into their own hands, the ministry had said cassava would be grown on no more than 450,000ha to prevent deforestation and, thus, soil erosion.
At a seminar held in northern Phu Tho Province on April 15, Deputy Minister of Agriculture and Rural Development Bui Ba Bong said the focus would be on increasing cassava yields to 17 tonnes per ha from the current 12 tonnes.
He called on authorities around the country to review cassava cultivation plans and ensure they dovetail with the country’s overall plan for cassava.
The crop is grown around the country and cultivated mostly in the central, Tay Nguyen (Central Highlands), and south-eastern regions.
It is a major component of animal feed for which around 1 million tonnes are used a year while it is also increasingly being used for ethanol production.
Last year Viet Nam exported 1.7 million tonnes of dried cassava and cassava products, 90 per cent of it to China, according to the General Department of Customs.