• Cropland, which includes all land currently used to grow crops, idle cropland, and cropland used only for pasture. Total cropland in the lower 48 states is approximately 408 million acres.2
  • Grassland pasture and range, including permanent grassland and other non-forested range and pasture, totals about 612 million acres.3
  • Forest-use land is total forestland as classified by the U.S. Department of Agriculture (USDA) Forest Service, excluding an estimated 80 million acres used primarily for parks, wildlife areas, and other uses. Forest-use land totals 576 million acres in the lower 48 states.4
  • Special-uses land includes areas for rural transportation, recreation and wildlife, various public installations and facilities, farmsteads, and farm roads, including the 80 million acres of forested land noted above. There are approximately 169 million acres in this category.5
  • Miscellaneous land includes areas in various uses not inventoried, marshes, open swamps, bare rock areas, desert, tundra, and other land generally of low agricultural value and total about 68 million acres.6
  • The urban land base includes streams and canals less than an eighth of a mile wide, and ponds, lakes, and reservoirs covering less than 40 acres. This category total about 60 million acres.7

Land use is not uniform across the United States but varies according to soil type, climatic conditions, and other facts. Figure 2-1 shows the major uses of land in 2007.

Biomass Resources

Stokes discussed some of the major forest and agricultural biomass resources that could serve as feedstocks. Forest resources include logging residues, which are very inexpensive to buy, but collecting them and converting them into something that can be transported can be expensive. Forest thinnings are trees removed for fire control or health improvements and the wood is usually not sellable, so it could be used as a feedstock resource. Conventional wood, in contrast, is marketable, but Stokes said that some of this wood may be diverted for use as a feedstock resource. Fuelwood is wood that goes to the pulp and paper industry for making heat and power for their plants. It also includes a few of the electrical power plants that use wood. Finally, there are the mill residues, pulping liquors, and urban wood resides, such as waste paper and yard trimmings, that could serve as energy feedstocks, though collection is the big issue because many of these are diffuse resources.

Agricultural resources include grains that go into biofuel production, oil crops, and crop residues. Energy crops include perennial grasses, such as switchgrass, bluestem, Miscanthus, and others, and perennial wood crops, which include poplar, willow, pine, and eucalyptus, among others. Agriculture also generates animal manures and food and feed processing residues that could serve as production feedstocks, as well as municipal solid waste, landfill gases, and annual energy crops such as sorghum.

He then reviewed the 2011 update of DOE’s Billion-Ton report, for which he was a co-lead. The Billion-Ton Update examines the nation’s capacity to produce a billion dry tons of biomass resources annually in the 48 coterminous states for energy uses without impacting other vital U.S. farm and forest products, such as food, feed, and fiber crops. The study provides industry, policy makers, and the agricultural community with county-level data and includes analyses of current U.S. feedstock capacity and the potential for growth in crops and agricultural products for clean energy applications. He noted that the 2011 study, unlike the earlier 2005 study, examined both current use and potential use up to 2030, and it included methodology to examine biomass potential at the county level. The 2011 study also included the costs for getting biomass to the roadside for transport and includes scenarios based on crop yields and tillage practices as well as sustainability criteria. The report, as well as all of the data, are available at www.bioenergykdf.net.

To develop county-level projections, Stokes and his colleagues used the POLYSYS economic model developed at the University of Tennessee Agricultural Policy Analysis Center (www.agpolicy.org). This model is anchored to the USDA’s 10-year baseline projections for eight major crops, and it includes projections for biomass resources that include corn stover, straws, and energy crops. The model also incorporates USDA-projected demands for food, feed, industry, and export, and works on a land base that includes

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2Nickerson, C., R. Ebel, A. Borchers, and F. Carriazo. 2011. Major Uses of Land in the United States, 2007. Economic Information Bulletin No. 89. December 2011 [online]. Available: http://www.epure.org/pdf/0w3ea6c0898164-d04c.pdf.

3Nickerson, C., R. Ebel, A. Borchers, and F. Carriazo. 2011. Major Uses of Land in the United States, 2007. Economic Information Bulletin No. 89. December 2011 [online]. Available: http://www.epure.org/pdf/0w3ea6c0898164-d04c.pdf.

4Nickerson, C., R. Ebel, A. Borchers, and F. Carriazo. 2011. Major Uses of Land in the United States, 2007. Economic Information Bulletin No. 89. December 2011 [online]. Available: http://www.epure.org/pdf/0w3ea6c0898164-d04c.pdf.

5Nickerson, C., R. Ebel, A. Borchers, and F. Carriazo. 2011. Major Uses of Land in the United States, 2007. Economic Information Bulletin No. 89. December 2011 [online]. Available: http://www.epure.org/pdf/0w3ea6c0898164-d04c.pdf.

6Nickerson, C., R. Ebel, A. Borchers, and F. Carriazo. 2011. Major Uses of Land in the United States, 2007. Economic Information Bulletin No. 89. December 2011 [online]. Available: http://www.epure.org/pdf/0w3ea6c0898164-d04c.pdf.

7Lubowski, R.N., M. Vesterby, S. Bucholtz, A. Baez, and M. Roberts. 2006. Major Uses of Land in the United States, 2002. Economic Information Bulletin No. (EIB-14) May 2006.



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