Farmers put ducks in a rice field in Zhuangxing village of Taiping town, Mishan city, Northeast China's Heilongjiang province, June 27, 2016. A method of rice farming that relies on ducks to eat insects and weeds has been introduced to Mishan since this year. It's an eco-friendly farming system, avoiding using toxic pesticides while also utilizing duck's droppings as fertilizer. (Photo/Xinhua)