The grassland-cropland margin
Land that moves between grassland and cultivated cropland is, by definition, at the margin between these uses. Nationally, the most active grassland-cultivated cropland margin between 1997 and 2007 was for hay. More than 26 million acres moved between cultivated crops and hay, resulting in a net shift of 4.8 million acres from cultivated crops to hay. More than 15 million acres moved between cultivated cropland and pasture, resulting in an overall shift of 5.5 million acres from cultivated crops to pasture. In contrast, the margin between cropland and rangeland involved less than 3.1 million acres. Roughly 1.3 million acres of range were converted to cultivated cropland, while 1.8 million acres went the other way for a net conversion from cultivated crops to range of about 500,000 acres. The CRP appeared to serve as a transitional land use between cultivated crop and forage production. Total CRP enrollment was roughly 32 million acres in both 1997 and 2007. During this period, however, 11.1 million acres of cultivated cropland were enrolled in the CRP for the first time while only 6.1 million acres were returned to cultivated crops. This chart is from the ERS report, Grassland to Cropland Conversion in the Northern Plains: The Role of Crop Insurance, Commodity, and Disaster Programs, ERR-120, June 2011.
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