The soybean plant belongs to the Leguminosae family. All plants in this family are known as legumes and many have the ability to supply their own nitrogen needs. The average composition of a soybean seed is 40 percent protein, 21 percent oil, 34 percent carbohydrates and 5 percent ash on a dry matter basis. Soybeans grown in Tennessee average about 20 percent oil and 40 percent protein. Soybeans are an important crop in Tennessee and rank in the top three for cash receipts for row crops each year. Soybean acres harvested for the last five years have ranged from 950,000 to 1,150,000 acres, with an average yield of 33.9 bushels per acre.
"PB1608 Soybean Production in Tennessee," The University of Tennessee Agricultural Extension Service, PB1608-1.5M-5/01 (Rev) R12-5210-07-001-01, http://trace.tennessee.edu/utk_agexcrop/51