In the U.S., farms spread from the colonies westward along with the settlers. In cooler regions, wheat was often the crop of choice when lands were newly settled, leading to a "wheat frontier" that moved westward over the course of years. Also very common in the antebellum Midwest was farming corn while raising hogs, complementing each other especially since it was difficult to get grain to market before the canals and railroads. After the "wheat frontier" had passed through an area, more diversified farms including dairy cattle generally took its place. Warmer regions saw plantings of cotton and herds of beef cattle. In the early colonial south, raising tobacco and cotton was common, especially through the use of slave labor until the Civil War. In the northeast, slaves were used in agriculture until the early 19th century. In the Midwest, slavery was prohibited by the Freedom Ordinance of 1787.
The introduction and broad adoption of scientific agriculture since the mid nineteenth century has made a large improvement in the USA's economic growth. This development was facilitated by the Morrill Act and the Hatch Act of 1887 which established in each state a land-grant university (with a mission to teach and study agriculture) and a federally-funded system of agricultural experiment stations and cooperative extension networks which place extension agents in each state.
Significant areas of farmland were abandoned during the Great Depression and incorporated into nascent national forests. Later, "Sodbuster" and "Swampbuster" restrictions written into federal farm programs starting in the 1970s reversed a decades-long trend of habitat destruction that began in 1942 when farmers were encouraged to plant all possible land in support of the war effort. In the United States, federal programs administered through local Soil and Water Conservation Districts provide technical assistance and partial funding to farmers who wish to implement management practices to conserve soil and limit erosion.
The top twenty agricultural products of the United States by value as reported by the FAO in 2003 (Products are ranked by their mass, multiplied by the 1999-2001 international prices. Mass is in metric tonnes):
|3.||Cow's milk, whole, fresh||78,155,000|
The only other crops to ever appear in the top 20 in the last 40 years were, commonly, tobacco, barley, and oats, and, rarely, peanuts, almonds, and sunflower seeds (in all, only 26 of the 188 crops the FAO tracks worldwide). Alfalfa and hay would both be in the top ten in 2003 if they were tracked by FAO.
Though (and perhaps because) marijuana is illegal in the United States, it is the largest cash crop by value of production with approximately $35.8 billion. The largest legal crops by value of production are:
|Major Crops in the U.S.A. - 1997|
(in US$ billions)
|Hay, other than alfalfa||$5.1|
1997 USDA-NASS reports,
Note alfalfa and hay are not tracked by the FAO and the production of tobacco in the U.S. has fallen 60% between 1997 and 2003.
The major livestock industries in the United States are:
Inventories in the United States at the end of 1997 were:
Goats, horses, turkeys and bees are also raised, though in lesser quantities. Inventory data is not as readily available as for the major industries. For the three major goat-producing states (AZ, NM, and TX) there were 1,200,000 goats at the end of 2002. There were 5,300,000 horses in the United States at the end of 1998. There were 2,500,000 colonies of bees at the end of 2002.
Labor laws prohibiting children in other workplaces provide some exemptions for children working on farms with complete exemptions for children working on their family's farm. Children can also gain permits from vocational training schools or the 4-H club which allow them to do jobs they would otherwise not be permitted to do.
A large part of the U.S. farm workforce is made up of migrant and seasonal workers, many of them recent immigrants from Latin America or aliens working under work permits. Additional laws apply to these workers and their housing which is often provided by the farmer.
In 2004, of the 145 million employed workers in the US, 834,000 of them held jobs as agricultural workers. 83% of these jobs were as farm workers. The median hourly income as of May 2004 was $7.70 for farmworkers planting, growing and harvesting crops, and $8.31 for farmworkers tending to animals.