H
Background Information on the Economic and Environmental Assessment of Biomass Supply

The tables in this appendix present the background information and assumptions that were used in the panel’s economic assessments and greenhouse gas emission analyses. They include comparisons of published and updated costs of harvest and maintenance (Table H.1), nutrient replacement (Table H.2), transportation for delivery (Tables H.3 and H.4), storage (Table H.5), and establishment and seeding (Table H.6) for different cellulosic feedstocks. Estimates of opportunity costs for cellulosic feedstocks are presented (Table H.7). The published yield values from which current and future projections were computed (Table H.8), and carbon inputs for feedstock production (Table H.9) and biomass refining (Table H.10) are also included.



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H Background Information on the Economic and Environmental Assessment of Biomass Supply T he tables in this appendix present the background information and assumptions that were used in the panel’s economic assessments and greenhouse gas emission analyses. They include comparisons of published and updated costs of harvest and maintenance (Table H.1), nutrient replacement (Table H.2), transportation for delivery (Tables H.3 and H.4), storage (Table H.5), and establishment and seeding (Table H.6) for different cellulosic feedstocks. Esti- mates of opportunity costs for cellulosic feedstocks are presented (Table H.7). The published yield values from which current and future projections were computed (Table H.8), and carbon inputs for feedstock production (Table H.9) and biomass refining (Table H.10) are also included. 

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 Liquid Transportation Fuels from Coal and Biomass TABLE H.1 Estimated Costs of Harvest and Maintenance for Cellulosic Feedstocks Cost per Ton Cost per Ton Type of Feedstock Type of Cost (cited $) (2007$) Reference Corn stover Baling, stacking, grinding 26 45 Hess et al. (2007) Corn stover Collection 31–36 66–77 McAloon et al. (2000) Corn stover Collection 35–46 64–84 McAloon et al. (2000) Corn stover Collection 17.70 17.70 R. Perlack, Oak Ridge National Laboratory, presentation to the committee on November 19, 2007 Corn stover Up to storage 20–21 36–39 Sokhansanj and Turhollow (2002) Corn stover 28 36 Suzuki (2006) Corn stover Baling, staging 26 47 Aden et al. (2002) Corn stover Harvest 14 14 Edwards (2007) Switchgrass Collection 12–22 16–28 Kumar and Sokhansanj (2007) Switchgrass Harvest 32 32 Duffy (2007) Switchgrass Harvest 35 58 Khanna et al. (2008) Switchgrass Harvest, maintenance, 123.5/acre 210/acre Khanna and Dhungana establishment (2007) Switchgrass Harvest 15 26 Perrin et al. (2008) Harvest 33 54 Khanna et al. (2008) Miscanthus Harvest, maintenance, 301/acre 512/acre Khanna and Dhungana Miscanthus establishment (2007) Nonspecific 10–30 15–45 Mapemba et al. (2007) Nonspecific 23 38 Mapemba et al. (2008) Note: Harvest and maintenance costs were updated by using USDA-NASS agricultural fuel, machinery, labor prices from 1999 to 2007 (USSA-NASS, 2007a,b).

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Appendix H  TABLE H.2 Estimated Costs of Nutrient Replacement for Cellulosic Feedstocks Cost per Ton Cost per Ton Type of Feedstock Type of Cost (cited $) (2007$) Reference Corn stover 10.2 14.1 Hoskinson et al. (2007) Corn stover 4.6 8.4 Khanna and Dhungana (2007) Corn stover 7 14.4 Aden et al. (2002) Corn stover 4.2 4.2 Petrolia (2008) Corn stover 10 21 Perlack and Turhollow (2003) Corn stover Whole-plant harvest 9.7 13.3 Karlen and Birrell (Unpublished) Corn stover Cob, top 50% harvest 9.5 13.1 Karlen and Birrell (Unpublished) Corn stover Bottom 50% harvest 10.1 13.9 Karlen and Birrell (Unpublished) Switchgrass 6.7 12.1 Perrin et al. (2008) Switchgrass 10.8 19.77 Khanna et al. (2008) 2.5 4.6 Khanna et al. (2008) Miscanthus Note: Nutrient and replacement costs were updated by using USDA-NASS agricultural-fertilizer prices from 1999 to 2007 (USDA-NASS, 2007a,b). TABLE H.3 Estimated Distance for Delivery of Cellulosic Feedstocks Distance (miles) Type Reference 46–134 Round-trip Mapemba et al. (2007) 22–62 One-way Perlack and Turhollow (2003) 22–61 One-way Perlack and Turhollow (2002) 50 Round-trip Khanna et al. (2008) 50 Max one-way English et al. (2006) 50 One-way Vadas et al. (2008)

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 Liquid Transportation Fuels from Coal and Biomass TABLE H.4 Estimated Costs of Transportation for Delivery of Cellulosic Feedstocks Cost per Ton Cost per Ton Type of Feedstock Type of Cost (cited $) (2007$) Reference Corn stover Per ton 8.85 12.5 English et al. (2006) Corn stover Per ton 10.25 27 Hess et al. (2007) DVCa Corn stover 0.15 0.35 Kaylen et al. (2000) Corn stover Max DVC for 0.28 0.66 Kaylen et al. (2000) positive NPV Corn stover Per ton 10.8 10.8 Perlack (2007) Corn stover Per ton 13 31 Aden et al. (2002) Corn stover Per ton 4.2–10.5 11–27.7 Perlack and Turhollow (2002) Corn stover DVC 0.08–0.29 0.17–0.63 Kumar et al. (2005) DFCb 4.5 9.8 DFC range 0–6 0–13.3 Corn stover DVC 0.18 0.32 Searcy et al. (2007) DFC 4 7.3 Corn stover DVC 0.16 0.38 Kumar et al. (2003) DFC 3.6 8.6 Corn stover DVC Petrolia (2008) 0-25 miles 0.13–0.23 0.13–0.23 25-100 miles 0.10–0.19 0.10–0.19 >100 miles 0.09–0.16 0.09–0.16 DFC square bales 1.70 1.70 DFC round bales 3.10 3.10 Corn stover Per ton 10.9 13.8 Vadas et al. (2008) Switchgrass Per ton 14.75 14.75 Duffy (2007) Switchgrass Per ton 19.2–23 27–32.4 Kumar and Sokhansanj (2007) Switchgrass Per ton 13 28 Perrin et al. (2008) Switchgrass Per ton 10.9 13.8 Vadas et al. (2008) Switchgrass or Per ton for 50 miles 7.9 17.1 Khanna et al. (2008) Miscanthus Nonspecific Per ton 7.4–19.3 13.7–35.6 Mapemba et al. (2007) Nonspecific Per ton 14.5 31.5 Mapemba et al. (2008) Woody biomass Per ton 11–22 Summit Ridge Investments (2007) Note: Transportation costs were updated by using USDA-NASS agricultural-fuel prices from 1999 to 2007 (USDA-NASS, 2007a,b). aDVC, distance variable cost, per ton per mile. bDFC, distance fixed cost per ton.

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Appendix H  TABLE H.5 Estimated Storage Costs for Cellulosic Feedstocks Cost per Ton Cost per Ton Type of Feedstock Type of Cost (cited $) (2007$) Reference Corn stover 4.44 5.64 Hess et al. (2007) Corn stover Round bales 6.82 6.82 Petrolia (2008) Square bales 12.93 12.93 Switchgrass 16.67 16.67 Duffy (2007) Switchgrass 4.14 5.18 Khanna et al. (2008) 4.40 5.50 Khanna et al. (2008) Miscanthus Nonspecific 2 2.18 Mapemba et al. (2008) Note: Storage costs were updated by using USDA-NASS agricultural-building material prices from 1999 to 2007 (USDA-NASS, 2007a,b). TABLE H.6 Estimated Costs of Establishment and Seeding for Cellulosic Feedstocks Type of Land Rent Cost per Acre Cost per Acre Feedstock Type of Cost Included (cited $) (2007$) Reference Switchgrass Yes 200 200 Duffy (2007) Switchgrass No 25.76 46 Perrin et al. (2008) Yes 85.46 153 PVa per ton Switchgrass No 7.21/ton 12.6/ton Khanna et al. 10-year PV per acre 142.3 249 (2008) Amortized 4% over 10 years 17.3 30.25 8% over 10 years 20.7 36.25 Switchgrass Yes 72.5–110 88.5–134 Vadas et al. (2008) PV per ton No 2.29/ton 4/ton Khanna et al. Miscanthus 20-year PV per acre 261 457 (2008) Amortized 4% over 20 years 19 33.2 8% over 20 years 26.20 45.87 Total No 1206–2413 Lewandowski Miscanthus Amortized (2003) 4% over 20 years 88–175 176–350 8% over 20 years 121–242 242–484 Note: Establishment and seeding costs were updated by using USDA-NASS agricultural fuel and seed prices from 1999 to 2007 (USDA-NASS, 2007a,b). aPV denotes present value.

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0 Liquid Transportation Fuels from Coal and Biomass TABLE H.7 Estimated Opportunity Costs for Cellulosic Feedstocks (Net Returns Forgone by Producer from Not Using Cropland to Produce Next Best Crop or Product) Type of Cost per Acre Cost per Acre Feedstock Type of Cost (cited $) (2007$) Reference Corn stover Feed value 59.5/ton 59.5/ton Edwards (2007) 2.4 tons/acre 142.8 142.8 Corn stover Lost profits 22–58 22–58 Khanna and Dhungana (2007) Switchgrass Lost profits 78–231 78–231 Khanna and Dhungana (2007) Switchgrass or Lost profits 78 76 Khanna et al. (2008) Miscanthus Lost profits 78–231 78–231 Khanna and Dhungana Miscanthus (2007) Lost CRPa payments if Nonspecific 35 36 Mapemba et al. (2008) harvest every year Nonspecific Lost CRP if harvest 10.1 10.4 Mapemba et al. (2008) once every 3 years Nonspecific Non-CRP land crops 10/ton 10.3/ton Mapemba et al. (2008) Nonspecific 78 76 Khanna et al. (2008) Woody biomass Alternative use 0–25 Summit Ridge Investments (2007) Note: Opportunity costs were updated by using USDA-NASS agricultural-land rent prices from 1999 to 2007 (USDA-NASS, 2007a,b). aConservation Reserve Program.

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Appendix H  TABLE H.8 Yield Values and Ranges for Different Bioenergy Feedstocks Reported in Literature Estimated Yield Biomass Type Assumptions (tons/acre) Reference Corn stover Soil tolerance 2.02 Khanna and Dhungana (2007) Corn stover 2.4 Edwards (2007) Corn stover 2000–2005 mean yields for 2.31–3 Vadas et al. (2008) Wisconsin Switchgrass Iowa, Illinois field trials 2.58 Khanna and Dhungana (2007) Switchgrass 4 Duffy (2007) Switchgrass Farm-scale (northern South 2.23 (5-year average) Perrin et al. (2008) Dakota to southern (Range, 1.7–2.7) Nebraska) 3.12 (10-year average) (Range, 2.6–3.5) Switchgrass 3.8 Khanna et al. (2008) 19.74 (10-year PV) Switchgrass Nitrogen level 4–5.8 Vadas et al. (2008) Switchgrass Research blocks 7.14 (average) Lewandowski et al. (2003) 9.8 (best) Switchgrass 3.6–8.9 (previous) Shinners et al. (2006) Plot trials 2.3–4 (own) Switchgrass Plot trials 6.33 Fike et al. (2006) 4.64–8.5 Switchgrass Field trials Berdahl et al. (2005) Mean 1.12–4.1 Strains: Dacotah 1.11–4.22 ND3743 0.91–3.92 Summer 1.18–4.38 Sunburst 1.43–5.57 Trailblazer 1.15–4.88 Shawnee 1.06–4.5 OK NU-2 0.89–4.18 Cave-in-Rock 0.97–4.27 Switchgrass Plot trials Vogel et al. (2002) Iowa 5.2–5.6 Nebraska 4.7–5 Switchgrass Peer-reviewed articles 4.46 Heaton et al. (2004a) continues

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 Liquid Transportation Fuels from Coal and Biomass TABLE H.8 Continued Estimated Yield Biomass Type Assumptions (tons/acre) Reference Switchgrass Farm trials Strains: Alamo (1 cut) 5.4–8.5 Kanlow (1 cut) 5.2–6.9 Cave-in-rock 6–8.3 (2 cut) Switchgrass U.S. average 4.2 McLaughlin et al. (2002) Grasses County-scale in Pacific 3.4–4.1 Banowetz et al. (2008) Northwest (perennial ryegrass) 4.13–6.2 (tall fescue) 2.2–3.36 (creeping red fescue) Simulated 8.9 Khanna and Dhungana Miscanthus (2007) 14.5 average Khanna et al. (2008) Miscanthus 12–17 range 114.58 (20-year PV) Field experiment 5.71 (14-year) Christian et al. (2008) Miscanthus 3.43–11.73 (3-year) 4.5–13.4 Lewandowski et al. (2003) Miscanthus Projection 13.36 (mean) Heaton et al. (2004b) Miscanthus 10.93–17.81 Peer-reviewed articles 9.8 Heaton et al. (2004a) Miscanthus

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Appendix H  TABLE H.9 Carbon Inputs to Biomass Agricultural Production Source of Input Cellulosic (kg CO2 eq/ha)a Corn Ethanol (Switchgrass) Nitrogen-fertilizer emissions 1638 547 Phosphorus 102 3.4 Potassium 70 2.4 Lime 228 — Herbicide 69 10.4 Insecticide 5.4 — Seed — — Transport emissions 39 3 Gasoline 114 — Diesel 248 341 Natural gas 46 — Liquefied petroleum gas 61 — Electricity 56 42 Energy used in irrigation 4 — Labor transportation — — Farm machinery 21 21 CO2 from land-use change (kg/ha) — — Total from agricultural production 2703 971 Conversion per acre 2452 lb CO2 eq/ac 881 lb CO2 eq/ac (0.405 ha/acre, 2.24 lb/kg) Conversion per ton — 220 lb CO2 eq/ton (assume 4 tons/acre) aUnless noted otherwise. Source: Farrell et al., 2006.

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 Liquid Transportation Fuels from Coal and Biomass TABLE H.10 Carbon Inputs to Biomass Refining, Including Transportation of Biomass Source of Input (g CO2 eq/L)a Corn Ethanol Cellulosic Transport of feedstock to biorefinery 49 51 Primary energy — — Diesel — 5 Coal 885 — Natural gas 365 — Electricity — — Biomass — — Capital (plant, equipment) 8.8 29 Process water 25 19 PWTPsb) Effluent restoration (BOD at 20 20 Transportation of chemicals to plant — — Total biorefinery phase 1,353 124 Coproduct credits 525 106 Total biorefinery phase accounting for 828 g CO2 eq/L 18 g CO2 eq/L coproduct Conversions: Initial value 828 g CO2 eq/L 18 g CO2 eq/L [0.4/0.4]/0.38 L/kg ~331.2 g CO2 eq/kg ~6.84 g CO2 eq/kg [8,746/8,389]/13,450 kg/ha ~2,896,675 g CO2 eq/ha ~91,998 g CO2 eq/ha 0.405 ha/acre ~1,173,153 g CO2 eq/ac ~37,259 g CO2 eq/ac 0.001 kg/g ~1,173 kg CO2e/ac ~37.3 kg CO2 eq/ac TOTAL 4,307 lb CO2 eq/ac 964 lb CO2 eq/ac (agriculture phase + biorefinery) Conversion per ton: — 241 lb CO2 eq/ton (assume 4 tons/acre) aUnless noted otherwise. bBiochemical oxygen demand of effluent at wastewater treatment plants. Source: Farrell et al., 2006.

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Appendix H  REFERENCES Aden, A., M. Ruth, K. Ibsen, J. Jechura, K. Neeves, J. Sheehan, B. Wallace, L. Montague, A. Slayton, and J. Lukas. 2002. Lignocellulosic Biomass to Ethanol Process Design and Economics Utilizing Co-Current Dilute Acid Prehydrolysis and Enzymatic Hydrolysis for Corn Stover. Golden, Colo.: National Renewable Energy Laboratory. Banowetz, G.M., A. Boatang, J.J. Steiner, S.M. Griffith, V. Sethi, and H. El-Nashaar. 2008. Assessment of straw biomass feedstock resources in the Pacific Northwest. Biomass and Bioenergy 32:629-634. Berdahl, J., A. Frank, J. Krupinsky, P. Carr, J. Hanson, and H. Johnson. 2005. Biomass yield, phenology, and survival of diverse switchgrass cultivars and experimental strains in western North Dakota. Agronomy Journal 97:549-555. Christian, D., A. Riche, and N. Yates. 2008. Growth, yield and mineral content of Miscanthus x Giganteus grown as a biofuel for 14 successful harvests. Industrial Crops and Products 28:320-327. Duffy, M. 2007. Estimated Costs for Production, Storage, and Transportation of Switchgrass. Iowa State University. Available at http://www.extension.iastate.edu/agdm/ crops/pdf/a1-22.pdf. Accessed April 22, 2008. Edwards, W. 2007. Estimating a Value for Corn Stover. Iowa State University. Available at http://www.extension.iastate.edu/agdm/crops/pdf/a1-70.pdf. Accessed May 22, 2008. English, B.C., D.G. de la Torre Ugarte, K. Jensen, C. Hellwinckel, J. Menard, B. Wilson, R. Roberts, and M. Walsh. 2006. 25% Renewable Energy for the United States by 2025: Agricultural and Economic Impacts. Knoxville: University of Tennessee. Farrell, A., R. Plevin, B. Turner, A. Jones, M. O’Hare, and D. Kammen. 2006. Ethanol can contribute to energy and environmental goals. Science 311:506-509. Fike, J., D. Parrish, D. Wolf, J. Balasko, J. Green, Jr., M. Rasnake, and J. Reynolds. 2006. Long-term yield potential of switchgrass-for-biofuel systems. Biomass and Bioenergy 30:198-206. Heaton, E., T. Voight, and S.P. Long. 2004a. A quantitative review comparing the yields of two candidate C4 perennial biomass crops in relation to nitrogen, temperature and water. Biomass and Bioenergy 27:21-30. Heaton, E.A., J. Clifton-Brown, T.B. Voight, M.B. Jones, and S.P. Long. 2004b. Miscanthus for renewable energy generation: European Union experience and projec- tions for Illinois. Mitigation and Adaptation Strategies for Global Change 9:433-451. Hess, J.R., C.T. Wright, and K.L. Kenney. 2007. Cellulosic biomass feedstocks and logistics for ethanol production. Biomass, Bioproduction and Biorefining 1:181-190. Hoskinson, R.L., D.L. Karlen, S.J. Birrell, C.W. Radtke, and W.W. Wilhelm. 2007. Engineering, nutrient removal, and feedstock conversion evaluations of four corn sto- ver harvest scenarios. Biomass and Bioenergy 31:126-136.

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 Liquid Transportation Fuels from Coal and Biomass Karlen, D.L., and S.J. Birrell. Unpublished. Crop Residue—What’s It Worth? U.S. Department of Agriculture and Iowa State University. Available at http://www1.eere. energy.gov/biomass/pdfs/Biomass_2009_Sustainabiliy_III_Karlen.pdf. Accessed April 25, 2009. Kaylen, M., D.L. Van Dyne, Y.S. Choi, and M. Blase. 2000. Economic feasibility of pro- ducing ethanol from lignocellulosic feedstocks. Bioresource Technology 72:19-32. Khanna, M., and B. Dhungana. 2007. Economics of Alternative Feedstocks in Corn- Based Ethanol in Illinois and the US: A Report from Department of Agricultural and Consumer Economics. Urbana-Champaign: University of Illinois. Available at http:// www.farmdoc.uiuc.edu/policy/research_reports/ethanol_report/Ethanol%20Report.pdf. Accessed April 25, 2009. Khanna, M., B. Dhungana, and J. Clifton-Brown. 2008. Costs of producing Miscanthus and switchgrass for bioenergy in Illinois. Biomass and Bioenergy 32(6):482-493. Kumar, A., and S. Sokhansanj. 2007. Switchgrass (Panicum vigratum, L.) delivery to a biorefinery using Integrated Biomass Supply Analysis and Logistics (IBSAL) Model. Bioresource Technology 98:1033-1044. Kumar, A., J. Cameron, and P. Flynn. 2003. Biomass power cost and optimum plant size in western Canada. Biomass and Bioenergy 24(6):445-464. Lewandowski, I., J. Scurlock, E. Lindvall, and M. Christou. 2003. The development and current status of perennial rhizomatous grasses as energy crops in the US and Europe. Biomass and Bioenergy 25(4):335-361. Mapemba, L.D., F.M. Epplin, R.L. Huhnke, and C.M. Taliaferro. 2008. Herbaceous plant biomass harvest and delivery cost with harvest segmented by month and number of harvest machines endogenously determined. Biomass and Bioenergy 32:1016-1027. Mapemba, L., F. Epplin, C. Taliaferro, and R. Huhnke. 2007. Biorefinery feedstock pro- duction on Conservation Reserve Program Land. Review of Agricultural Economics 29(2):227-246. McAloon, A., F. Taylor, W. Yee, K. Ibsen, and R. Wooley. 2000. Determining the Cost of Producing Ethanol from Corn Starch and Lignocellulosic Feedstocks. Golden, Colo.: National Renewable Energy Laboratory. McLaughlin, S.B., D.G. de la Torre Ugarte, C.T. Garten, Jr., L.R. Lynd, M.A. Sanderson, V.R. Tolbert, and D.D. Wolf. 2002. High-value renewable energy from prairie grasses. Environmental Science and Technology 36:2122-2129. Perlack, R., and A. Turhollow. 2002. Assessment of Options for the Collection, Handling, and Transport of Corn Stover. Oak Ridge, Tenn.: Oak Ridge National Laboratory. Perlack, R., and A. Turhollow. 2003. Feedstock cost analysis of corn stover residues for further processing. Energy 28:1395-1403.

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Appendix H  Perlack, R. 2007. Overview of Plant Feedstock Production for Biofuels: Current Technologies, Challenges, and Potential Improvement. Presentation to the National Research Council Committee on Alternative Liquid Transportation Fuels. Washington, D.C., November 19, 2007. Perrin, R., K. Vogel, M. Schmer, and R. Mitchell. 2008. Farm-scale production cost of switchgrass for biomass. Bioenergy Research 1:91-97. Petrolia, D.R. 2008. The economics of harvesting and transporting corn stover to fuel ethanol: A case study for Minnesota. Biomass and Bioenergy 32(7):603-612. Searcy, E., P. Flynn, E. Ghafoori, and A. Kumar. 2007. The relative cost of biomass energy transport. Applied Biochemistry and Biotechnology 137-140(1-12):639-652. Shinners, K.J., G.C. Boettcher, R.E. Muck, P.J. Weimer, M.D. Casler. 2006. Drying, har- vesting, and storage characteristics of perennial grasses as biomass feedstocks. ASABE Paper No. 061012. St. Joseph, Mich.: American Society of Agricultural and Biological Engineers. Sokhansanj, S., and A. Turhollow. 2002. Baseline cost for corn stover collection. Applied Engineering and Agriculture 18:525-530. Summit Ridge Investments, LLC. 2007. Eastern Hardwood Forest Region Woody Biomass Energy Opportunity. Granville, Vt: Summit Ridge Investments. Suzuki, Y. 2006. Estimating the Cost of Transporting Corn Stalks in the Midwest. Ames: Iowa State University College of Business: Business and Partnership Development. USDA-NASS (U.S. Department of Agriculture, National Agricultural Statistics Service). 2007a. Agricultural Prices 2006 Summary. Washington, D.C.: U.S. Department of Agriculture, National Agricultural Statistics Service. USDA-NASS. 2007b. Agricultural Prices December 2007. Washington, D.C.: U.S. Department of Agriculture, National Agricultural Statistics Service. Vadas, P.A., K.H. Barnett, and D.J. Undersander. 2008. Economics and energy of ethanol production from alfalfa, corn, and switchgrass in the Upper Midwest, USA. Bioenergy Research 1:44-55. Vogel, K., J. Brejda, D. Walters, and D. Buxton. 2002. Switchgrass biomass production in the Midwest USA: Harvest and nitrogen management. Agronomy Journal 94:413-420.

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