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The United States possesses some of the best farmland in the world.Total farmland represents 42％ of the nation’s total land area and almost all of that is under cultivation.American farmers enjoy favorable climate，rich soil and plenty of water resources.As a result，U.S.farms produce large quantities of agricultural products and livestock.The vast farm output enables American farmers to supply about half of all world grain exports.With high levels of mechanization and technology，as well as good organization，American farmers are very efficient.Today the average size of farms in the United States is around 440 acres，but some farms in the West are much larger.

American staple agricultural products include corn，soybeans，wheat，hay，rice，tobacco，sorghum，vegetables，fruits and sugarcane.The United States produces more corn，soybeans and sorghum than any other country in the world.Corn is the country’s largest and the most important grain crop.Corn production is concentrated heavily in the mid⁃western region known as the Corn Belt.The United States is also the world’s second largest producer of wheat，citrus fruits and tobacco.Cotton used to be a very important commercial crop in the South，but its importance has declined due to the invention of synthetic fibers.

America also produces large amounts of meat and dairy products.Cattle ranches and other livestock farms are mainly located on the Great Plains and in the Corn Belt.Texas is the leading cattle producing state.Dairy farming areas are mainly located in New England，the Midwest and the Pacific Northwest.

American agriculture has generally been very successful.However，because of the huge size of the U.S.economy，agricultural products accounted for only about 1.2％ of the nation’s GDP as of 2011.The success of farming in the United States has created a problem of overproduction.As many American farmers depend on international markets to sell some or all of their products，shortfalls in demand can lead to sharp drops in prices，causing farmers to suffer large economic losses.

From the 1930s on，the federal government’s agricultural policy has aimed to raise prices of farm products by limiting production.In addition，the government has adopted price support systems under which it buys up surplus farm products when prices fall below a given floor.