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Million hectares


State and trends


Cropland area trends


The land area dedicated to crop production in 2012 was 146.9 million hectares. This is an increase of 1.56 million hectares since 2007; the first reported increase since 1982 (USDA 2015a; Figure 2.2.1). Despite this recent overall gain, the longer term trend was loss of cropland. Increases in urban land are responsible for part of this decline. Trends in land-use change since 2007 have not been analyzed in a consolidated and comprehensive way because updated information from the Natural Resources Conservation Service’s National Resources Inventory (NRI) report is absent.


The Conservation Reserve Programme—which provided financial incentives to farmers to take highly erodible and other marginal land out of production—lost 3.34 million hectares between 2007 and 2012, nearly 2.22 million hectares or 77 per cent of which had been planted grasslands and lands formerly used for pasture or hay production. Lark et al. (2015) found that the principal crops grown on this new cropland were maize, 26 per cent; wheat, 25 per cent; soybeans, 20 per cent; and alfalfa, 7 per cent. However, they did not attribute the crop production gains to a driving force, such as shifting commodity prices or biofuels mandates.


Figure 2.2.1: US Cropland, by year


10 0 120 14 0 16 0 180


6 0 80


4 0 20


0 19 82 19 87 19 9 2 19 9 7 Years


ultivated ropland Nonultivated ropland


Source: US Department of Agriculture 2012 20 0 2 20 0 7 20 12


Developed land increased by 1.23 million hectares, or 2.7 per cent. Forty-six per cent of that was converted forest, 37 per cent rangeland and pastureland, and 23 per cent cropland.


Grazing land area trends


Pastureland and grazing land estimates vary for the US, depending on the data source and definitions. The National Resources Inventory (NRI) of the Natural Resources Conservation Service classifies 49.0 million hectares as pasture and an additional 164.2 million hectares as rangeland, of an estimated total 213 million hectares (USDA 2015b). The 2012 Census of Agriculture, on the other hand, classifies 168.1 million hectares as pasture or rangeland for grazing, plus 11.3 million hectares of woodland grazed, for a total of 175.4 million hectares – an increase of 7.3 million hectares since 2007. A broader estimate of land available for grazing from a third Department of Agriculture agency, the Economic Research Service, totals about 248.7 million hectares, and includes grassland and other non-forested pasture and rangeland (US EPA 2010). If forestlands used for grazing and cropland pasture are also included, the total estimate for grazing lands is 314.4 million hectares for 2007, representing 35 per cent of US land area (US EPA 2010). However, three to four year delays by the Natural Resources Conservation Service in releasing the NRI information from the 2007 and 2012 surveys have prevented the Economic Research Service from updating the data (Nickerson et al. 2011, Figure 2.2.2). This lack of timeliness in processing and releasing data significantly reduces the usefulness of the NRI for policy and generates confusion for analysts.


Forest area trends


Forests are managed by a complex array of interests to meet multiple purposes, including recreation, public water supplies, timber production, and providing habitat for a variety of species. Oswalt et al. (2014) reported 310 million hectares of forestland in the US in 2012, of which 211 million hectares were considered as ‘timberland’—land with no constraints on harvesting wood. Forests that are not timberland include land reserved from timber production, such as designated


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