Agriculture is a major industry in the United States, which is a net exporter of food. As of the 2017 census of agriculture, there were 2.04 million farms, covering an area of , an average of per farm.
Agriculture in the United States is highly mechanized, with an average of only one farmer or farm laborer required per square kilometer of farmland for agricultural production.
Although agricultural activity occurs in every U.S. state, it is particularly concentrated in the Central Valley of California and in the Great Plains, a vast expanse of flat arable land in the center of the nation, in the region west of the Great Lakes and east of the Rocky Mountains. The eastern wetter half is a major corn and soybean-producing region known as the Corn Belt, and the western drier half is known as the Wheat Belt because of its high rate of wheat production. The Central Valley of California produces fruits, vegetables, and nuts. The American South has historically been a large producer of cotton, tobacco, and rice, but it has declined in agricultural production over the past century. Florida leads the nation in citrus production and is the number two producer of oranges in the world behind only Brazil.
The U.S. has led developments in seed improvement, such as hybridization, and in expanding uses for crops from the work of George Washington Carver to bioplastics and biofuels. The mechanization of farming and intensive farming have been major themes in U.S. history, including John Deere's steel plow, Cyrus McCormick's mechanical reaper, Eli Whitney's cotton gin, and the widespread success of the Fordson tractor and the combine harvester. Modern agriculture in the U.S. ranges from hobby farms and small-scale producers to large commercial farms that cover thousands of acres of cropland or rangeland.
History
Corn, turkeys, tomatoes, potatoes, peanuts, and sunflower seeds constitute some of the major holdovers from the agricultural endowment of the Americas.
Colonists had more access to land in the colonial United States than they did in Europe. The organization of labor was complex including free persons, slaves and indentured servants depending on the regions where either slaves or poor landless laborers were available to work on family farms.
European agricultural practices greatly affected the New England landscape. Colonists brought livestock over from Europe which caused many changes to the land. Grazing animals required a lot of land and food and the act of grazing itself destroyed native grasses, which were being replaced by European species. New species of weeds were introduced and began to thrive as they were capable of withstanding the grazing of animals, whereas native species could not.
The practices associated with keeping livestock also contributed to the deterioration of the forests and fields. Colonists would cut down the trees and then allow their cattle and livestock to graze freely in the forest and never plant more trees. The animals trampled and tore up the ground so much as to cause long-term destruction and damage.
Soil exhaustion was a huge problem in New England agriculture. Farming with oxen did allow the colonist to farm more land but it increased erosion and decreased soil fertility. This was due to deeper plow cuts in the soil that allowed the soil more contact with oxygen causing nutrient depletion. In grazing fields in New England, the soil was being compacted by the large number of cattle and this did not give the soil enough oxygen to sustain life.