Soybeans are an edible legume native to Asia and are an important source of protein in many modern diets. Chinese farmers first domesticated soybeans around 1100 BC. Since that time, cultures around the world have cultivated the crop as a food source. In the 1920s, the A.E. Staley Manufacturing Company began crushing soybeans and produced two new products: unrefined soybean oil and defatted soybean meal. The former soon became an important ingredient in margarine and shortening, while the latter became a staple in livestock feed. Farmers plant seeds in rows, and in four to seven days they sprout into plants. The planting season in the United States is between May and July, and harvesting occurs around September when the crop has fully matured. Soybeans grow in very similar conditions to corn, so many farmers grow both crops on the same acreage.