Tongwei specialty sainfoin, known as the "queen of pasture", is a perennial herb of sainfoin in Leguminosae. Strong cold and drought resistance, high yield, early maturity of seeds, comprehensive and balanced nutrition, and livestock like to eat. It can be used for 4-6 years once planted. The biggest feature is that cattle and sheep will not swell after eating. Nodules can fix nitrogen, improve soil fertility and effectively prevent soil erosion, which has the advantages of less labor, less investment and quick effect. In 1980s, under the careful guidance of Wang, an expert in grass industry, Gansu sainfoin was successfully planted in Shenjiashan, Longyang Township, Tongwei County, which made sainfoin stand out among many pastures. At that time, with the promotion of national policies, Tongwei County made a breakthrough in pasture planting, with an area of 320,000 mu. Tongwei once became the national planting center of sainfoin and the largest pasture county in the province, and visited Xinjiang, Ningxia and Inner Mongolia. In recent years, Tongwei County has placed grass industry in a prominent position and regarded sainfoin as the dominant grass species in Tongwei County. Animal husbandry departments play a functional role, cooperate with water and soil conservation, forestry, poverty alleviation and other departments to establish demonstration bases and carry out technical training. In the first half of 2003 alone, 42,000 mu of sainfoin was newly planted in the county, with a seedbed area of 1.43 million mu. It is the county with the largest planting area in the province, providing about 280 tons of seeds to all parts of the country and selling them to Sichuan, Tibet, Qinghai, Inner Mongolia and other places.