<P> 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 and floods . </P> <P> Tonnes of United States agriculture production, as reported by the FAO in 2003 and 2013 (ranked roughly in order of value): </P> <Table> <Tr> <Td> Millions of Tonnes in </Td> <Td> 2003 </Td> <Td> 2013 </Td> </Tr> <Tr> <Td> Corn </Td> <Td> 256.0 </Td> <Td> 354.0 </Td> </Tr> <Tr> <Td> Cattle meat </Td> <Td> 12.0 </Td> <Td> 11.7 </Td> </Tr> <Tr> <Td> Cow's milk, whole, fresh </Td> <Td> 77.0 </Td> <Td> 91.0 </Td> </Tr> <Tr> <Td> Chicken meat </Td> <Td> 14.7 </Td> <Td> 17.4 </Td> </Tr> <Tr> <Td> Soybeans </Td> <Td> 67.0 </Td> <Td> 89.0 </Td> </Tr> <Tr> <Td> Pig meat </Td> <Td> 9.1 </Td> <Td> 10.5 </Td> </Tr> <Tr> <Td> Wheat </Td> <Td> 64.0 </Td> <Td> 58.0 </Td> </Tr> <Tr> <Td> Cotton lint </Td> <Td> 4.0 </Td> <Td> 2.8 </Td> </Tr> <Tr> <Td> Hen eggs </Td> <Td> 5.2 </Td> <Td> 5.6 </Td> </Tr> <Tr> <Td> Turkey meat </Td> <Td> 2.5 </Td> <Td> 2.6 </Td> </Tr> <Tr> <Td> Tomatoes </Td> <Td> 11.4 </Td> <Td> 12.6 </Td> </Tr> <Tr> <Td> Potatoes </Td> <Td> 20.8 </Td> <Td> 19.8 </Td> </Tr> <Tr> <Td> Grapes </Td> <Td> 5.9 </Td> <Td> 7.7 </Td> </Tr> <Tr> <Td> Oranges </Td> <Td> 10.4 </Td> <Td> 7.6 </Td> </Tr> <Tr> <Td> Rice, paddy </Td> <Td> 9.1 </Td> <Td> 8.6 </Td> </Tr> <Tr> <Td> Apples </Td> <Td> 3.9 </Td> <Td> 4.1 </Td> </Tr> <Tr> <Td> Sorghum </Td> <Td> 10.4 </Td> <Td> 9.9 </Td> </Tr> <Tr> <Td> Lettuce </Td> <Td> 4.7 </Td> <Td> 3.6 </Td> </Tr> <Tr> <Td> Cottonseed </Td> <Td> 6.0 </Td> <Td> 5.6 </Td> </Tr> <Tr> <Td> Sugar beets </Td> <Td> 30.7 </Td> <Td> 29.8 </Td> </Tr> </Table> <Tr> <Td> Millions of Tonnes in </Td> <Td> 2003 </Td> <Td> 2013 </Td> </Tr>

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