For many years, farmers in Vinh Kien District - on the edge of Yen Bai and Tuyen Quang provinces - watched heavy rains wash away the soil of their farms, eroding the best soil layer for growing cassava. Many local households rely on cassava for their incomes, as well as on traditional rice paddy cultivation. And soil erosion has become much worse recently, as downpours grow more aggressive.
To recover this problem, the International Centre for Tropical Agriculture (CIAT) has give a new technique to help farmers protect their land from soil loss. Accordingly, residents just have to plant a few strips of paspalum grass, better known as ‘horse grass’ among the locals like green stripes decorating the hills of cassava. Finally, results are striking. The performance nearly double compared to the cassava she harvested before, since starting to grow grass with cassava, instead of just growing cassava. After just 3 or 4 years the hills was transformed into a slope with horizontal green and bronze "steps" from a steep 45o incline. Also, grass grown on the village head’s ha of hill land turned out to have another positive effect as food for animals.
Van Yen Agricultural Extension Station Deputy Head Doan Manh Cuong, “Cassava degrades soil fast. Couple that with unpredictable weather in recent years, and it became urgent that we find a way to make cassava production sustainable. Growing horse grass in strip patterns slows down rainwater flow, sustains soil fertility, and reduces the amount of fertilizers farmers must use. Horse grass cuts down production costs for farmers.”
CIAT first introduced the horse grass strip technique in Van Yen commune 14 years ago. It soon spread and became a hit with cassava-growing localities. From growing 1,000 ha of cassava-with-grass-strips in 2002, local farmers now grow about 6,700 ha in Van Yen district, a seven-fold increase. Success in Van Yen inspired CIAT to help farmers elsewhere who are still struggling to adjust their traditional agricultural ways with weather which continues to grow ever harsher. The technique was part of a bigger project by CIAT to provide farmers with agricultural technologies to enhance adaptability to climate change. Farming villages in Viet Nam and across Southeast Asia were targeted. The project was implemented simultaneously in three provinces, including Yen Bai, Nghe An and Bac Lieu provinces.