U.S. flagAn official website of the United States government
                    Here's how you know **Official websites use .gov**
                            
                            A **.gov** website belongs to an official government organization in the United States.
 **Secure .gov websites use HTTPS**
                            
                            A **lock** (                            
                              A locked padlock                                                      
                            
                            ) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


Menu Agricultural Research Service
						
                    U.S. DEPARTMENT OF AGRICULTURE
 Rangeland Resources & Systems Research: Fort Collins, CO
 close



    Research

                    Research Projects
                                    Publications
                                    Collaborations
                                    News
                                    Software
                People

                    Staff Listing
                                    Careers


        


                    Areas of Research
                        CARM
                                    PHACE
                                    Thunder Basin
                                    Modeling
                                    WindSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Plains Area Fort Collins, Colorado Center for Agricultural Resources Research Rangeland Resources & Systems Research Docs Range







Past Scientist Publicationsheadline bar Jack Morgan
Terry Booth
Dick Hart
Gerald SchumanGary Fraisier
Jean Reeder
Marilyn Samuels
Charlie Townsend Dr. Jack Morgan--Plant Physiologist Retired 2013
I am a retired plant physiologist/collaborator with the Rangeland Resources Research Unit, USDA-Agricultural Research Service.   My training and experience have been in photosynthesis, plant/soil water relations, and physiological plant ecology of native grasslands, and my research emphasis has been in understanding the effects of global climate change on western rangelands. Increases in atmospheric CO2 concentrations have important implications for rangelands as they are predicted to cause major changes in the global climate, and may already be affecting weather patterns and productivity of western rangelands. Rising ambient CO2 concentrations will also impact rangelands through their direct effects on photosynthesis, plant growth, water relations, N metabolism and forage quality, and secondarily through effects on soil biology and mineral cycling. Much of my career has been spent conducting research to better understand how future CO2-enriched atmospheres, warmer temperature and altered precipitation will affect the ecology and sustainability of Great Plains grasslands, and using that knowledge to develop management practices that will be appropriate for future environments. Return to top Selected Publications: Reyes-Fox, M. , H. Steltzer, M. J. Trlica, G. S. McMaster, A. A. Andales, D. R. LeCain and **J. A. Morgan**.  2014. Long-term exposure to elevated CO2 enhances plant community stability by suppressing dominant plant species in a mixed grass prairie.  *Nature* 510:259-262. Suseela, V., D. Triebwasser-Freese, N. Linscheid,  **J.A. Morgan**, and N. Tharayil.  2014.  Litters of photosynthetically divergent grasses exhibit differential metabolic responses to warming and elevated CO2  *Ecosphere* 5(9): art 106. Zelikova, T.J.,  D. M. Blumenthal, D. G. Williams, L. Souzac, D.R. LeCain, **J. Morgan**, and Elise Pendall.  2014.  Long-term exposure to elevated CO2 enhances plant community stability by suppressing dominant plantspecies in a mixed-grass prairie.  *PNAS* Early Edition. Cruz J. L., A. A. C. Alves, D. R. LeCain, D. D. Ellis, **J. A. Morgan**. 2014. Effect of elevated CO2 concentration and nitrate: ammonium ratios on gas exchange and growth of cassava(Manihot esculenta Crantz). *Plant Soil* 374:33-43; DOI 10.1007/s11104-013-1869-8 Pendall, E., J. L. Heisler-White, D. G. Williams, F. A. Dijkstra, Y. Carrillo, J. A. Morgan, and D. R. LeCain.  2013.  Warming reduces carbon loses from grassland exposed to elevated atmospheric carbon dioxide.  *PLOS On*e 8 (8): e71921. Polley, H.W., D. D. Briske,  **J. A. Morgan**, K. Wolter, D. W. Bailey, and J. R. Brown.  2013.  Climate change and North American Rangelands: Trends, projections, and implications.  *Rangeland, Ecology and Management* 66:493-511. Ponce Campos, G. E., M. S. Moran, A. Huete, Y.  Zhang, C. Bresloff, T. E. Huxman, D. Eamus, D. D. Bosch, A. R. Buda, S. A. Gunter, T.  Heartsill Scalley, S. G. Kitchen, M. P. McClaran, W. H. McNab, D. S. Montoya, **J. A. Morgan,** D. P. C. Peters, E. J. Sadler, M. S. Seyfried & P. J. Starks. 2013. Ecosystem resilience despite large-scale altered hydroclimatic conditions. *Nature*, doi: 10.1038/nature11836 Dijkstra, F. A.  , **J. A. Morgan** , R. F. Follett, and D. R. Lecain. 2013. Climate change reduces the net sink of CH4 and N2O in a semiarid grassland. *Global Change Biology*  19:1816-1826, doi: 10.1111/gcb.12182 Blumenthal, D. M., V. Resco, **J. A. Morgan**, D. G. Williams, D. R. LeCain, E. M. Hardy, E. Pendall, and E. Bladyka. 2013. Invasive forb benefits from water savings by native plants and carbon fertilization under elevated CO2 and warming.*New Phytologist*, doi: 10.1111/nph.12459. Walthall, C. L., J. Hatfield, P. Backlund, L. Lengnick, E. Marshall, M. Walsh, S. Adkins, M. Aillery, E. A. Ainsworth, C. Ammann, C. J. Anderson, I. Bartomeus, L. H. Baumgard, F. Booker, B. Bradley, D. M. Blumenthal, J. Bunce, K. Burkey, S. M. Dabney, J. A. Delgado, J. Dukes, A. Funk, K. Garrett, M. Glenn, D. A. Grantz, D. Goodrich, S. Hu, R. C. Izaurralde, R. A. C. Jones, S. H. Kim, A. D. B. Leaky, K. Lewers, T. L. Mader, A. McClung, **J. Morgan,** D. J. Muth, M. Nearing, D. M. Oosterhuis, D. Ort, C. Parmesan, W. T. Pettigrew, W. Polley, R. Rader, C. Rice, M. Rivington, E. Rosskopf, W. A. Salas, L. E. Sollenberger, R. Srygley, C. St?ckle, E. S. Takle, D. Timlin, J. W. White, R. Winfree, L. Wright-Morton, and L. H. Ziska. 2013. Climate change and agriculture in the United States: effects and adaptation. USDA Technical Bulletin 1935. Washington, DC. 186 pages Perry, L. G., P. B. Shafroth, D. M. Blumenthal, **J. A. Morgan**, and D. R. LeCain.  2013.  Elevated CO2 does not offset greater water stress predicted under climate change for native and exotic riparian plants.  *New Phytologist* 19:532-543. Dijkstra, F. A., E. Pendall, J. A. Morgan, D.M. Blumenthal, Y. Carillo, D. R. LeCain, R. F. Follett, and D. G. Williams. 2012. Climate change alters stoichiometry of phosphorus and nitrogen in semiarid grassland. *New Phytologist* 196:807-815. Dieleman,W. I. J., S. Vicca , F. A. Dijkstra, F. Hagedorn, M. J. Hovenden, K. S. Larsen, J. A. Morgan, A. Volder, C. S Beier, J. S. Dukes, J. King, S. Leuzinger, S. Linder, Y. Luo, R. Oren, P. DeAngelis, D. Tingey, M. R. Hoosbeek and I. A. Janssens. 2012. Simple additive effects are rare: a quantitative review of plant biomass and soil process responses to combined manipulations of CO2 and temperature. Global Change Biology 18: 2681-2693. LeCain, D. R, J. A. Morgan, G. L. Hutchinson, J. D. Reeder and F. A. Dijkstra. 2012. Interactions between elevated atmospheric CO2 and defoliation on North American rangeland plant species at low and high N availability. *Grass and Forage Science*, 67: 350-360. Dijkstra, F. A. and J. A. Morgan. 2012. Elevated CO2 and warming effects on soil carbon sequestration and greenhouse gas exchange in agroecosystems: A review. Chapter 27 IN M.A. Liebig, A.J. Franzluebbers, and R.F. Follett (Eds.), Managing Agricultural Greenhouse Gases: Coordinated Agricultural Research through GRACEnet to Address our Changing Climate, 547 pp, Elsevier, London, UK; New York, USA. Carrillo, Y., F. A. Dijkstra, E. Pendall, J. A. Morgan, and D. M. Blumenthal. 2012. Controls over soil nitrogen pools in a semiarid grassland under elevated CO2 and warming. *Ecosystems* 15:761-774. Parton, W, J. Morgan, D. Smith, S. DelGrosso, L. Prihodko, D. Lecain, R. Kelly and S. Lutz. 2012. Impact of precipitation dynamics on net ecosystem productivity. *Global Change Biology*18:915-927 Follett, R. F., S. Mooney, J. A. Morgan, K. Paustian, L. H. Allen, Jr., S. Archibeque, S. J. Del Grosso, and J. D. Derner, et al. 2011. Carbon sequestration and greenhouse gas fluxes in agriculture: Challenges and opportunities. Task Force Report No. 142, 106 pp, Council for Agricultural Science and Technology Ames, Iowa, USA. Izaurralde, R. C., A. M. Thomson, J. A. Morgan, P. A. Fay, H. W. Polley and J. L. Hatfield. 2011. Climate Impacts on Agriculture: Implications for Forage and Rangeland Production. *Agronomy Journal* 103:371-381. Polley, H. W., R. L. Phillips, A. B. Frank, J. A. Bradford, P. L. Sims, J. A. Morgan, and J. R. Kiniry. 2011. Variability in Light-Use Efficiency for Gross Primary Productivity on Great Plains Grasslands. *Ecosystems* 14:15-27. Jamiyansharav, K., D. Ojima, R.A. Pielke Sr., W. Parton, J. Morgan, A. Beltr?n-Przekurat, D. LeCain, and D. Smith. 2011.Seasonal and interannual variability in surface energy partitioning and vegetation cover with grazing at shortgrass steppe. *Journal Arid Environments* 75:360-370. Dijkstra, F. A., J. A. Morgan, J. C. von Fischer, and R. F. Follett. 2011. Elevated CO2 and warming effects on CH4 uptake in a semiarid grassland below optimum soil moisture. *Journal of Geophysical Research*, 116, G01007, doi:10.1029/2010JG001288. Dijkstra, F. A., G. L. Hutchinson, J. D. Reeder, D. R. LeCain, and J. A. Morgan. 2011. Elevated CO2, but not defoliation, enhances N cycling and increases short-term soil N immobilization regardless of N addition in a semiarid grassland. *Soil Biology and Biochemistry* 43:2247-2256. Morgan, J. A., D. R. LeCain, E. Pendall, D. M. Blumenthal, B. A. Kimball, Y. Carrillo, D. G. Williams, J. Heisler-White, F. A. Dijkstra, and M. West. 2011. C4 grasses propser as carbon dioxide eliminates desiccation in warmed semi-arid grassland. *Nature* 476:202-206. Carrillo, Y., E. Pendall, F. A. Dijkstra, J. A. Morgan, and J. M. Newcomb. 2011. Response of soil organic matter pools to elevated CO2 and warming in a semi-arid grassland. *Plant Soil* 347:339-350. Augustine, D. J., F. A. Dijkstra, E. W. Hamilton III and J. A. Morgan. 2011. Rhizosphere interactions, carbon allocation, and nitrogen acquisition of two perennial North American grasses in response to defoliation and elevated atmospheric CO2. *Oecologia* 165:755-770. Chimner, R., J. M. Welker, J. A. Morgan, D. R. LeCain and J. Reeder. 2010. Experimental manipulations of winter snow and summer rain influence ecosystem carbon cycling in a mixed-grass prairie, Wyoming, USA. *Ecohydrology* 3:284-293 Polley,H. W., J. A. Mogan and P. A. Fay. 2010. Application of a conceptual framework to interpret variability in rangeland responses to atmospheric CO2 enrichment. *Journal of Agricultural Science*  1-14. Dijkstra, F. A., D. Blumenthal, J. A. Morgan, D. R. LeCain and R. F. Follett. 2010. Elevated CO2 effects on semi-arid grassland plants in relation to water availability and competition. *Functional Ecology* 24:1152-1161. Dijkstra, F. A., J. A. Morgan, D. Blumenthal, R. F. Follett. 2010. Water limitation and plant inter-specific competition reduce rhizosphere-induced C decomposition and plant N uptake.*Soil Biology and Biochemistry* 42:1073-1082. Dijkstra, F. A., D. Blumenthal, J. A. Morgan, E. Pendall, Y. Carrillo, and R. F. Follett. 2010. Contrasting effects of elevated CO2 and warming on nitrogen cycling in a semiarid grassland. *New Phytologist* 187: 426-437. Dijkstra,F. A., J. A. Morgan, D. R. LeCain, R.F. Follett. 2010. Microbially mediated CH4 consumption and N2O emission is affected by elevated CO2, soil water content, and composition of semi-arid grassland species. *Plant Soil*  329:269-281. Polley, H. W., W. Emmerich, J. A. Bradford, P. L. Sims, D. A. Johnson, N. Z. Saliendra, T. Svejcar, R. Angell, A. B. Frank, F. L. Phillips, K. A. Snyder, and J. A. Morgan. 2010. Physiological and environmental regulation of interannual variability in CO2 exchange on rangelands in the western United States. *Global Change Biology* 16:990-1002. Morgan, J. A., R. F. Follett, L. H. Allen, Jr., S. D. Grosso, J. D. Derner, F. Dijkstra, A. Franzluebbers, R. Fry, K. Paustian, and M. M.Schoeneberger. 2010. Carbon sequestration in agricultural lands of the United States.*Journal of Soil and Water Conservation* 65:6A-13A. Bachman, S., J. L. Heisler-White, E. Pendall, D. G. Williams, J. A. Morgan, J. Newcomb. 2009. Elevated carbon dioxide alters impacts of precipitation pulses on ecosystem photosynthesis and respiration in a semi-arid  grassland. *Oecologia* 162:791-802. Shim, J. H., E. Pendall, J. A. Morgan, and D. S. Ojima. 2009. Wetting and drying cycles drive variations in the stable carbon isotope ratio of respired carbon dioxide in semi-arid grassland.*Oecologia* doi 10.1007/s00442-009-1302-4. Alfieri, J., P. Blanken, J. A. Morgan, and D. P. Smith. 2009. Concerning the measurement and magnitude of heat, water vapor, and carbon dioxide exchange from a semiarid grassland.*Journal of Applied Meteorology and Climatology* 48:982-996. Schuman, G. E., L. J. Ingram, P. D. Stahl, J. D. Derner, G. F. Vance, and J. A. Morgan. 2009.Influence of management on soil organic carbon dynamics in northern mixed-grass rangeland. In: R. Lal and R.F. Follett (eds.). Soil carbon sequestration and the greenhouse effect. Soil Science Society of America, Special Publication 57, second edition, Madison, WI. pp. 169-180. Kimball, B. A., M. M. Conley, S. Wang, L. Xingwu, J. A. Morgan and D. P. Smith. 2008. Infra-red heater arrays for warming ecosystem field plots. *Global Change Biology* 14:309-320 Dijkstra, F. A, E. Pendall, A. Mosier, J. King, D. Milchunas, and J. A. Morgan. 2008. Long-term enhancement of N availability and plant growth under elevated CO2 in a semiarid grassland. *Functional Ecology* doi:10.1111/j.1365-2435.2008.01398.x. Svejcar, A. J., R. F. Angell, J. Bradford, W. Dugas, W. E. Emmerich, A. B. Frank, T. Gilmanov, M. R. Haferkamp, D. A. Johnson, H. S. Mayeux Jr, P. Mielnick, J. A. Morgan, N. Saliendra, G. E. Schuman, P. L. Sims, K. A. Snyder. 2008. Carbon fluxes on North American rangelands. *Rangeland Ecology & Management* 61:465-474. Ainsworth, E. A., C. Beier, C., Calfapietra, R. Cuelemans, M. Durand-Tardif, G. D. Farquhar, D. L. Godbold, G. R. Hendrey, T. Hickler, J. Kaduk, D. J. Karnosky, B. A. Kimball, C. Koerner, M. Koornneef, T. Lafarge, A. D. B. Leakey, K .F. Lewin, S. P. Long, R. Manderscheid, D. L. McNeil, T. A. Meis, F. Miglietta, J. A. Morgan, J. Nagy, R. J. Norby, R. M. Norton, K. E. Percy, A. Rogers, J. Soussana, M. Stitt, H. Weigel, and J. W. White. 2008. Next generation of elevated [CO2] experiments with crops: A critical investment for feeding the future world. *Plant Cell and Environment* 31:1317-1324. Burke, I. C., Lauenroth, W. K., Antolin, M. F., Derner, J. D., Milchunas, D. G., Morgan, J. A., Stapp, P. 2008. The future of the shortgrass steppe. In: W.K. Lauenroth and I.C. Burke (eds.). Ecology of the shortgrass steppe: A long?term perspective. Oxford University Press, Oxford, England. pp. 484?510. Lauenroth, W.K., Burke, I.C., Morgan, J.A. 2008. The shortgrass steppe: The region and research sites. In: W.K. Lauenroth and I.C. Burke (eds.). Ecology of the shortgrass steppe: A long?term perspective. Oxford University Press, Oxford, England. pp. 3?13. Lauenroth, W.K., Milchunas, D.G., Sala, O.E., Burke, I.C., and Morgan, J.A. 2008. Net primary production in the shortgrass steppe: A long?term perspective. Oxford University Press, Oxford, England. pp. 270?305. Svejcar, T., R. Angell, J. A. Bradford, W. Dugas, W. Emmerich, A. B. Frank, T. Gilmanov, M. Haferkamp, D. A. Johnson, H. Mayeux, P. Mielnick, J. Morgan, N. Z. Saliendra, G. E. Schuman, P. L. Sims, and K. Snyder. 2008. Carbon Fluxes on North American Rangelands.*Rangeland Ecology & Management* 61:465-474 Morgan, J. A., J. D. Derner, D. G. Milchunas, and E. Pendall. 2008. Management implications of global change for Great Plains rangelands. *Rangelands* 30:18-22. Norton, U., A. R. Mosier, , A. R., J. A. Morgan, J. D. Derner, L. J. Ingram, and P. D. Stahl. 2008. Moisture pulses, trace gas emissions and soil C and N in cheatgrass and native grass-dominated sagebrush-steppe in Wyoming, USA. *Soil Biology & Biochemistry* 40:1421-1431. Ayers, E., D. H. Wall, B. L. Simmons, C. B. Field, D. Milchunas, J. A. Morgan and J. Roy. 2008. Belowground grassland herbivores are resistant to elevated atmospheric CO2 concentrations in grassland ecosystems. *Soil Biology and Biochemistry* 40:978-985. Kandeler, E., A. R. Mosier, J. A. Morgan, D. G. Milchunas, J. Y. King, S. Rudolph, and D. Tscherko. 2008. Transient elevation of carbon dioxide modifies the microbial community composition in a semi-arid grassland. *Soil Biology and Biochemistry* 40:162-171. Parton, W. J., J. A. Morgan, G. Wang and S. Del Grosso. 2007. Projected ecosystem impact of the Prairie Heating and CO2 Enrichment experiment.*New Phytologist*174:823-834. K?rner, C., J. A. Morgan and R. Norby. 2007. CO2 fertilization: When, where, and how much? In: Canadell JG, Pataki DE, Pitelka LF (eds) Terrestrial Ecosystems in a Changing World. The IGBP Series. pp 9-22. Springer, Berlin. Wylie, B. K., E. A. Fosnight, T. G. Gilmanov, A. B. Frank, J. A. Morgan, M. R. Haferkamp and T. P. Meyers. 2007. Adaptive Data-Driven Models for Estimating Carbon Fluxes in the Northern Great Plains. *Remote Sensing of Environment* 106:399-413. Morgan, J. A., D. G. Milchunas, D. R. LeCain, M. S. West and A. Mosier. 2007. Carbon dioxide enrichment alters plant community structure and accelerates shrub growth in the shortgrass steppe. Proceedings of the Natl Academy of Sciences, 104(37):14724-14729. LeCain, D. L., J. A. Morgan, D. G. Milchunas, A. R. Mosier, J. A. Nelson and D. P. Smith. 2006. Root biomass of individual species, and root size characteristics after five years of CO2 enrichment on native shortgrass steppe. *Plant and Soil* 279:219-228. Milchunas, D. G., A. R. Mosier, J. A. Morgan, D. R. LeCain, J. Y. King and J. Y. Nelson. 2005. Root production and tissue quality in a shortgrass steppe exposed to elevated CO2: Using a new ingrowth method.*Plant and Soil* 268:111-122. Pendall, E., J. Y. King, A. R. Mosier, J. Morgan and D. Milchunas. 2005. Stable isotope constraints on net ecosystem production under elevated CO2. In: L.B. Flanagan, J.R. Ehleringer and D.E. Pataki (eds) Stable Isotopes and Biosphere-Atmospheric Interactions: Processes and Biological Controls. pp 182-198. Elsevier Inc., San Diego, CA. Milchunas, D. G., A. R. Mosier, J. A. Morgan, D. R. LeCain, J. Y King and J. A. Nelson. 2005. Elevated CO2 and defoliation effects on a shortgrass steppe: forage quality versus quantity for ruminants. *Agriculture, Ecosystems and Environment* 111:166-184. Milchunas, D. G., J. A. Morgan, A. R. Mosier and D. R. LeCain. 2005. Root dynamics and demography in shortgrass steppe under elevated CO2, and comments on minirhizotron methodology. *Global Change Biology* 11:1837-1855. Gilmanov, T. G., L. L. Tieszen, B. K. Wylie, L. B. Flanagan, A. B. Frank, M. R. Haferkamp, T. P. Meyers and J. A. Morgan. 2005.Integration of CO2 flux and remotely sensed data for primary production and ecosystem respiration analyses in the Northern Great Plains: Potential for quantitative spatial extrapolation.*Global Ecology and Biogeography* 14:271-292. Derner, J. D., G. E. Schuman, M. Jawson, S. R. Shafer, J. A. Morgan, H. W. Polley, G. B. Runion, S. A. Prior, H. A. Torbert, H. H. Rogers, J. Bunce, L. Ziska, J. W. White, A. J. Franzluebbers, J. D. Reeder, R. Venterea and L. A. Harper. USDA-ARS Global Change Research on Rangelands and Pasturelands.*Rangelands* 27:36-42. Nelson, J. A., J. A. Morgan, D. R. LeCain, A. R. Mosier, D. G. Milchunas, and B. A. Parton. 2004. Elevated CO2 increases soil moisture and enhances plant water relations in a long-term field study in semi-arid shortgrass steppe of Colorado.*Plant and Soil* 259:169-179. Morgan, J. A., A. R. Mosier, D. G. Milchunas, D. R. LeCain, J. A. Nelson and W. J. Parton. 2004. CO2 enhances productivity, alters species composition, and reduces forage digestibility of shortgrass steppe vegetation.*Ecological Applications* 14:208-219. Reeder, J. D., G. E. Schuman, J. A. Morgan, and D. R. LeCain. 2004. Response of organic and inorganic carbon and nitrogen stocks to long-term grazing of the shortgrass steppe. *Environmental Management* 10.1007/s00267-003-9106-5. Pendall, A. R. Mosier, and J. A. Morgan. 2004. Rhizodeposition stimulated by elevated CO2 in a semi?arid grassland. *New Phytologist* 162:447-458 Reeder, J. D., G. E. Schuman, J. A. Morgan and D. R. LeCain. 2004. Response of organic and inorganic carbon and nitrogen stocks to long-term grazing of the shortgrass steppe. *Environmental Management* 33:485-495. King, J.Y., A.R. Mosier, J.A. Morgan, D.R. LeCain, D.G. Milchunas and W.J. Parton. 2004. Plant nitrogen dynamics in shortgrass steppe under elevated atmospheric CO2. Ecosystems 7:147-160. Milchunas, D.G., J.Y. King, A.R. Mosier, J.C. Moore, J.A. Morgan, M.H. Quirk and J.R. Slusser. 2004. UV radiation effects on plant growth and forage quality in a shortgrass steppe ecosystem. Photochemistry and Photobiology 79:404-410. Pendall, E., A. R. Mosier and J. A. Morgan. 2004. Rhizodeposition stimulated by elevated CO2 in a semi arid grassland. *New Phytologist* 162:447-458. Morgan, J. A., D. E. Pataki, C. Korner, H. Clark, S. J. DelGrosso, J. M. Grunzewig, A. K. Knapp, A. R. Mosier, P. C. D. Newton, P. A. Niklaus, J. B. Nippert, R. S. Nowak, W. J. Parton, H. W. Polley and M. R. Shaw. 2004. Water relations in grassland and desert ecosystems to elevated atmospheric CO2. *Oecologia* 140:11-25. Liebig, M. A., J. A. Morgan, J. D. Reeder, B. H. Ellert, H. T. Gollany and G. E. Schuman. 2004. Greenhouse Gas Contributions and Mitigation Potential of Agricultural Practices in Northwestern USA and Western Canada. ASA Meetings (abstract). Ferretti, D. F., E. Pendall, J. A. Morgan, J. A. Nelson, D. R. LeCain and A. R. Mosier. 2003. Partitioning evapotranspiration fluxes from a Colorado grassland using stabel isotopes: seasonal variations and implication for elevated atmospheric CO[1] 2. *Plant and Soil* 254:291-303. Pendall, E., S. Del Grosso, J. Y. King, D. R. LeCain, D. G. Milchunas, J. A. Morgan, A. R. Mosier, D. S. Ojima, W. A. Parton, P. P. Tans, and J. W. C. White. 2003. Elevated atmospheric CO2 effects and soil water feedbacks on soil respiration components in a Colorado grassland. *Global Biogeochemical Cycles* 17:1-13. LeCain, D. R., J. A. Morgan, A. R. Mosier and J. A. Nelson. 2003. Soil and plant water relations, not photosynthetic pathway, primarily influence photosynthetic responses in a semi-arid ecosystem under elevated CO2. *Annals of Botany* 92:41-52. Mosier, A. R., E. Pendall, and J. A. Morgan. 2003. Effect of water addition and nitrogen fertilization on the fluxes of CH4, CO2, NOx, and N2O following five years of elevated CO2 in the Colorado Shortgrass Steppe. *Atmospheric Chemistry and Physics Discussions* 3:1-6. King, J., D. Milchunas, A. Mosier, Moore, J. Morgan, Slusser. 2003. Initial Impacts of Altered UVB Radiation on Plant Growth and Decomposition in Shortgrass Steppe. International Society for Optical Engineering Annual Meeting. Morgan, J. A. 2002. Looking beneath the Surface. *Science* 298: 1903-1904. Lecain, D. R., J. A. Morgan, G. S. Schuman and J. D. Reeder, and R. H. Hart. 2002. Carbon exchange rates and species composition of grazed pastures and exclosures in the shortgrass steppe of Colorado. *Agriculture, Ecosystems and Environment* 93:421-435. Gill, R. A., R. H. Kelly, W. J. Parton, K. A. Day, R. B. Jackson, J. A. Morgan, J. M. O. Scurlock, L. L. Tieszen, J. van de Castle, D. S. Ojima, and X. S. Zhang. 2002. Using simple environmental variables to estimate belowground productivity in grasslands. *Global Ecology and Biogeography* 11:79-86. Mosier, A. R., J. A. Morgan, J. Y. King, D. LeCain and D. G. Milchunas. 2002. Soil-atmosphere exchange of CH4, CO2, NOx, and N2O in the Colorado Shortgrass Steppe under Elevated CO2. *Plant and Soil* 240:201-211. Derner, J. D., D. T. Booth, J. A. Morgan, G. E. Schuman and J. D. Reeder. 2002. High Plains Grasslands Research Station - Changing to meet the challenges of a new century. *Cow Country* 130:4-5 Morgan, J. A., A. R. Mosier, D. R. LeCain, W. J. Parton and D. G. Milchunas. 2001. Elevated CO2 enhances productivity and the C/N ratio of grasses in the Colorado shortgrass steppe. Proceedings of the XIX International Grassland Congress. pp 981-982. Brazilian Society of Animal Husbandry, Sao Pedro, Sao Paulo, Brazil. Morgan, J. A., P. C .D. Newton, J. N?sberger and C. E. Owensby. 2001. The influence of rising atmospheric CO2 on grassland ecosystems. Proceedings of the XIX International Grassland Congress. pp 973-980. Brazilian Society of Animal Husbandry, Sao Pedro, Sao Paulo, Brazil.. Reeder, J. D., G. E. Schuman, J. A. Morgan, D. R. LeCain and R. H. Hart. 2001. Impact of grazing management strategies on carbon sequestration in a semi-arid rangeland, USA. Proceedings of the XIX International Grassland Congress. pp 211-213. Brazilian Society of Animal Husbandry, Sao Pedro, Sao Paulo, Brazil. XIX International Grassland Congress. Morgan, J. A., R. H. Skinner, and J. D. Hanson. 2001. Nitrogen and CO2 affect regrowth and biomass partitioning differently in forages of three functional groups. *Crop Science* 41:78-86. Morgan, J. A., D. R. LeCain, A. R. Mosier, and D. G. Milchunas. 2001. Elevated CO2 enhances water relations and productivity and affects gas exchange in C3 and C4 grasses of the Colorado Shortgrass Steppe. *Global Change Biology* 7:451-466. Schuman, G. E., D. R. LeCain, J. D. Reeder, and J. A. Morgan. 2001. Carbon dynamics and sequestration of a mixed-grass prairie as influenced by grazing. pp. 67-75. In: R. Lal (ed.)Soil Carbon Sequestration and the Greenhouse Effect. Soil Sci. Soc. Am., Special Publ. No. 57. Soil Science Society of America, Madison, WI LeCain, D. R., J. A. Morgan, G. E. Schuman, J. D. Reeder, and R. H. Hart. 2000. Carbon exchange rates in grazed and ungrazed pastures of Wyoming. Journal Range Management. 53: 199-206. Parton, W.J., J.A. Morgan, R.H. Kelly and D. Ojima. 2000. Modeling soil C responses to environmental change in grassland systems. pp 371-398. In R.F. Follet, J.M. Kimble and R. Lal (eds) The Potential of U.S. Grazing Lands to Sequester Carbon and Mitigate the Greenhouse Effect, Lewis Publishers, New York.  Dr. D. T. "Terry" Booth - Rangeland Scientist, Retired 2012
I began my career with the Soil Conservation Service in Nevada and later served at USDA-SCS Plant Materials Centers in Tucson, AZ, and Aberdeen, ID, in programs to enhance the revegetation of lands disturbed by road building and mining. Subsequently, I continued that work with the USDA-ARS in Cheyenne but with a greater focus on seed science and technology to enhance the use of native species in mined-land revegetation. These investigations were carried out with the help of Larry W. Griffith and ranged from studies of seed physiology and seedbed ecology to concerns with seed harvest, handling, and seed storage. In 2000 I changed programs to continue remote sensing work I began in Paul T. Tueller's laboratory at the University of Nevada Reno. James H. Everitt and Pilot Rene Davis, USDA-ARS, Weslaco, TX, graciously hosted me on a memorable visit to their laboratory that was helpful in solidifying my key research ideas. USDI-Bureau of Land Management, Wyoming State Office funded a Technical Assistant position most ably filled by Samuel E. Cox. Together we developed the world's highest resolution, multi-camera, aerial-imaging system for monitoring rangelands. The system collected up to 3 simultaneous images at each sample location from <1 to ~20 mm per pixel ground sample distance (GSD). The high detail captured by these images made it impractical to use standard image-analyses software. We addressed this by working with Bob Berryman to develop SamplePoint and other tools for high-resolution image analysis (http://www.samplepoint.org). Our imaging system revealed the degraded condition of most rangeland riparian areas we surveyed. This is degradation that is facilitating downstream flooding such as occurred in the Missouri River Basin in 2011 (http://www.nws.noaa.gov/os/assessments/pdfs/Missouri_floods11.pdf). Further, there are numerous publications documenting the loss of mountain glaciers and snowpack to a warming earth. High-elevation storage of solid water is the source of western water. A warming earth means land management-especially public-land management-must do much more to protect and improve riparian systems (liquid-water storage) to compensate for losses in frozen-water storage. My most recent publications address this issue. The US West and other regions of the world are facing critical shortages of surface and ground water. Better informed decision making and effective land-management to recover and enhance the water-storage capacities of our rangeland riparian systems-including the aquifer recharge functions-is essential to sustaining western water supplies.  Return to top page PUBLICATIONS: **Booth**,**D. T.,** J. C. Likins, S. E. Cox, J. B. Norton, and R. C. Anderson-Sprecher. 2021. Grazing Increases Soil Warming in Headwater Wetlands: Importance to Land Managers and Water Users. *Ecosystems*doi.org/10.1007/s10021-021-00701-0 Cox, S. E., **D. T. Booth**, R.D. Berryman. 2021. Measuring nested frequency of plants from digital images with SampleFreq.Ecological Indicators 121: 106946 S. E. Cox,**D. T. Booth**, J. C. Likins. 2016. Headcut Erosion in Wyoming's Sweetwater Subbasin.*Environmental Management* (2016) 57:450-462, DOI 10.1007/s00267-015-0610-1 Hunt, E.R., C. Wang, **D.T. Booth**, S.E. Cox, L. Kumar, M.C. Reeves. 2016. Remote sensing of rangeland biodiversity. In: P.S. Thenkabail (ed). Remote Sensing Handbook, Volume II - Land Resources Monitoring, Modeling, and Mapping with Remote Sensing. CRC Press, Boca Raton, pp.275-293. **** **Booth, D.T**. and S.E. Cox. 2015. Resource management in rangelands. In: T. Mueller and G.F. Sassenrath (eds), *GIS Applications in Agriculture.* CRC Press, Boca Raton, pp. 151-170. Moffet, C.A., Taylor, J.B.,**Booth, D.T**. 2015. Postfire shrub cover dynamics: a 70-year fire history in mountain big sagebrush communities.*Journal of Arid Environments.* 114:116-123. **Booth, D.T.,** Cox, S.E., Likens, J.C. 2014. Fenceline contrasts: Grazing increases wetland surface.*Wetlands Ecology and Management*. 23:183-194. Gearhart, A., **D. T. Booth** , K. Sedivec & C. Schauer. 2013. Use of Kendall's coefficient of concordance to assess agreement among observers of very high resolutin imagery.*Geocarto International*, 28:517-526, DOI:10.1080/10106049.2012.725775 Beck, J.L., **Booth, D.T**., Kennedy, C.L. 2014. Assessing greater sage-grouse breeding habitat with aerial and ground imagery. *Rangeland Ecology and Management*. 67:328-332. Weber, K.T., Chen, F., **Booth, D.T.,** Raza, M., Serr, K., Gokhale, B. 2013. Comparing two ground-cover measurement methodologies for semiarid rangelands.*Rangeland Ecology and Management.* 66:82-87. Booth, D.T., Cox, S.E., Simonds, G., Sant, E. 2012. Willow cover as a recovery indicator under a conservation grazing plan. Journal of Ecological Indicators. 18:512-519. Augustine, D.J.,**Booth, D.T.,** Cox, S.E., Derner, J.D. 2012. Grazing intensity and spatial heterogeneity in bare soil in a grazing-resistant grassland.*Rangeland Ecology and Management.* 65:39-46. Mealor, B. A., S. Cox, and **D.T. Booth**. 2012. Postfire Downy Brome (Bromus tetorum) invasion at high elevations in Wyoming.*Invasive Plant Science and Management.* 5:427-435. Blumenthal, D. M., A. P. Norton, S. E. Cox, E. M. Hardy, G. E. Liston, L. Kennaway, **D. T. Booth**, and J. D. Derner. 2011. Linaria dalmatica invades south-facing slopes and less grazed areas in grazing-tolerant mixed-grass prairie.*Biological Invasions, 14:395-404,* doi: 10.1007/s10530-011-0085-9. Cagney, J., S. E. Cox, and **D. T. Booth**. 2011. Comparison of Point Intercept and Image Analysis for Monitoring Rangeland Transects.*Rangeland Ecology Management* 64:309-315. **Booth, D.T.** and S.E. Cox. 2011. Art to Science: Tools for Greater Objectivity in Resource Monitoring. *SRM Rangelands*, August ,p 27-34. **Booth D.T.,** Cox S.E., Teel D. 2010. Aerial assessment of leafy spurge (Euphorbiaesula L.) on Idaho's Deep Fire Burn. *Native Plants Journal* 11(3):327-339. **Booth, T.** and J. Hildreth. 2009. A.C. Hildreth: Initiating USDA agriculture research in Cheyenne.Around Cheyenne  3:2:72-73. **Booth, D.T.** and S.E. Cox. 2009. Dual-camera, high-resolution aerial assessment of pipeline revegetation. *Environmental Monitoring and Assessment* 158:23-33. Cox, S.E. and **D.T. Booth.** 2009. Shadow attenuation with high dynamic range images: Creating RGB images that allow feature classification in areas otherwise obscured by shadow or oversaturation. *Environment Monitoring Asses*s 158231-241, DOI 10.1007/s10661-008-0577-y **Booth, D.T**., S.E. Cox, G.E. Simonds, and B. Elmore.  2009.  Efficacy of two variations on an aerial lek-count method for greater sage-grouse. *Western North American Naturalist* 69:413-416 **Booth, D.T.** , S.E. Cox, T. Meikle and H. Zuuring. 2008. Ground-Cover Measurements: Assessing Correlation Among Aerial and Ground-Based Methods. *Environmental Management*, DOI 10.1007/s00267-008-9110-x Sivanpillai, R. and D.T. Booth. 2008. Characterizing rangeland vegetation using Landsat and 1-mm VLSA data in central Wyoming (USA).*Agroforest System* 73:55-64 **Booth, D.T.,** and S.E. Cox. 2008. Image-based monitoring to measure ecological change on rangelands.*Frontiers in Ecology and the Environment* 6, doi:10.1890/070095 Blumenthal, D., **D.T. Booth**, S.E. Cox, C. Ferrier.  2007.  Large-scale aerial images capture details of plant populations.*Rangeland Ecology and Management* 60:523-528. **Booth, D.T.,** S.E. Cox and G.E. Simonds. 2007. Riparian monitoring using 2-cm GSD aerial photography. *Journal of Ecological Indicators* 7:636-648. Seefeldt, S.S. and **D.T. Booth**. 2006. Measuring plant cover in sagebrush steppe rangelands: a comparison of methods. *Environmental Management* 37:703-711. **Booth, D.T.,** S.E. Cox, and R.D. Berryman. 2006. Precision measurements from very large scale aerial digital imagery.*Environmental Monitoring and Assessment* 112:293-307. **Booth, D.T.,** S.E. Cox, T.W. Meikle and C. Fitzgerald. 2006. The accuracy of ground cover asurements. *Rangeland Ecology and Management* 59:179-188. Booth, D.T. and K.P. Vogel. 2006. Revegetation priorities. *Rangelands* 28(5):24-30. **Booth, D.T.,** S.E. Cox and R.D. Berryman. 2006. Point Sampling Digital Imagery with 'SamplePoint'.*Environmental Monitoring and Assessment* 123:97-108. **Booth, D.T.** and S.E. Cox. 2006. Very-large scale aerial photography for rangeland monitoring.*Geocarto International.* 21: 27-34. **Booth, D.T.,** S.E. Cox, C. Fifield, M. Phillips and N. Williamson. 2005. Image analysis compared with other methods for measuring ground cover.*Arid Land Research and Management* 19:91-100. **Booth, D. T.,** S.E. Cox, and D.E. Johnson. 2005. Detection-threshold calibration and other factors influencing digital measurements of bare ground. *Rangeland Ecology and Management* 58:598-604. VanAmburg, L.K., D.T. Booth, M.A. Weltz and M.J. Trlica. 2005. A laser point frame to measure cover.*Rangeland Ecology and Management* 58(5):557-560. **Booth, D.T.** 2005. Establishing Wyoming big sagebrush seed orchards on reclaimed mine land. *Native Plant Journal* 6:247-253. Booth, D.T., S.E. Cox., M. Louhaichi, and D.E. Johnson. 2004. Technical Note: Lightweight camera stand for close-to-earth remote sensing. *Journal Range Management* 57:675-678. **Booth, D.T.** and P.T. Tueller. 2003. Rangeland monitoring using remote sensing. *Journal of Arid Land Research and Management* 17:455-478. Bai, Y., C.R. Tischler, **D.T. Booth** and E.M. Taylor. 2003. Variation in germination and grain quality within rust resistant common wheat germplasm as affected by parental C02 conditions. *Environmental and Experimental Botany* 50:159-168. **Booth, D.T.**, *Y. Bai* and E.E. Roos. 2003. Wyoming big sagebrush seed production from mined and un-mined rangelands. *Journal of Range Management* 56:542-546. Hunt, E.R., J.H. Everitt, J.C. Ritchie, M.S Moran, **D.T. Booth**, and G.L. Anderson. 2003. Applications and Research Using Remote Sensing for Rangeland Management. *Photogrammetric Engineering and Remote Sensing* 69:675-694. **Booth, D.T.** 2002. Seed longevity and seeding strategies affect sagebrush revegetation. *Journal of Range Management* 55:188-193. Thygerson, T., J.M. Harris, B.N. Smith, L.D. Hansen, R.L. Pendleton and **D.T. Booth**. 2002. Metabolic response to temperature for six populations of winterfat (*Eurotia lanata*). *Thermochimica Acta* 394:211-217. **Booth, D.T.** and T.A. Jones. 2001. Plants for ecological restoration: a foundation and a philosophy for the future. *Native Plants Journal* 2:12-20. **Booth, D.T.** and S. Sowa.  2001. Respiration in dormant and non-dormant bitterbrush seeds. *Journal Arid Environments* 48:35-39. Olson, R.A., J.K. Gores, **D.T. Booth**, and G.E. Schuman. 2000. Suitability of shrub establishment on Wyoming mined lands reclaimed for wildlife habitat. *Western North American Naturalist.* 60:77-92. Booth, D.T., J.K. Gores, G.E. Schuman, and R.A. Olson. 1999.  Shrub densities on pre-1985 reclaimed mine lands in Wyoming.*Restoration Ecology* 7:24-32. Bai, Y., **D.T. Booth**, and J.T. Romo. 1999. Imbibition temperature affects winterfat(Eurotia lanata (Pursh) Moq.) seed hydration and cold-hardiness response. *Journal Range Management.* 52:271-274. Booth, D.T., R. Agustrina, and R.H. Abernethy. 1999. Evidence of cell deterioration in winterfat seeds during refrigerated storage.*Journal Range Management*. 52:290-295. Bai, Y., S.P. Hardegree, **D.T. Booth**, and E.E. Roos. 1999.  Pericarp removal has little effect on sagebrush seeds. *Journal Range Management*. 52:384-386. Hou, J.Q., J.T. Romo, Y. Bai, and **D.T. Booth**. 1999. Responses of winterfat seeds and seedlings to desiccation. *Journal Range Management* 52:387-393. **Booth, D.T.** and Y. Bai. 1999. Imbibition temperature affects on seedling vigor: In crops and shrubs. *Journal Range Management*. 52:534-538. **Booth, D.T.** 1999. Imbibition temperatures affect bitterbrush seed dormancy and seedling vigor.*Journal Arid Environments* 43:91-101. Bai. Y., **D.T. Booth** and J.T. Romo. 1998. Winterfat (*Eurotia lanata*(Pursh) Moq.) seedbed ecology: Low temperature exotherms and cold hardiness in hydrated seeds as influenced by imbibition temperature. *Annals of Botany* 81:595-602. **Booth, D.T.** and Y. Bai. 1998. Technical Note: Measuring moisture content of small seeds. *Journal of Range Management* 51:179-180. Schuman, G.E., **D.T. Booth** and J.R. Cockrell. 1998. Cultural methods for establishing Wyoming big sagebrush on mined lands. *Journal of Range Management* 51:223-230. Welbaum, G.E, K.J. Bradford, K.-O. Yim, **D.T. Booth** and M.O. Oluoch. 1998.  Physiological control of radicle emergence. *Seed Science Research*. 8:161-172. Bai, Y., **D.T. Booth** and E.E. Roos. 1997. Effect of seed moisture on Wyoming big sagebrush seed quality. *Journal of Range Management* 50:419-422. **Booth, D.T.**, Y. Bai and E.E. Roos. 1997. Preparing sagebrush seed for market: effects of debearder processing. *Journal of Range Management* 50:51-54. **Booth, D.T.** and Haferkamp, M.R., 1995. Morphology and seedling establishment. *Wildland plants: physiological ecology and developmental morphology*. Denver (CO): Society for Range Management, pp.168-238. **Booth, D.T.** and L.W. Griffith. 1994. Technical Note: Measuring post-germination growth. *Journal of Range* *Management* 47:503-504. **Booth, D.T.** and M.B. McDonald. 1994. Cation concentration in post-imbibed winterfat seeds as influenced by imbibition temperature. *Journal of Range Management* 47:485-488. **Booth, D.T.** and D.R. Morgan. 1993. Post-germination growth related to time-to-germination for four woody plants. *Journal of Seed Technology* 16:30-38. **Booth, D.T.** 1992. Seedbed ecology of winterfat: Imbibition temperature affects post-germination growth.*Journal of Range Management* 45:159-164. **Booth, D.T.** 1990. Seedbed ecology of winterfat: Effects of mother-plant transpiration, wind stress and nutrition on seedling vigor. *Journal of Range Management* 43:20-24. **Booth, D.T.** 1990. Plant diaspore functions. *Journal of Seed Technology* 14:61-73. Morgan*,*D.R. and **D.T. Booth**. 1990. Sodium concentration in germination blotters. *Journal of Range Management* 43:276. Schuman, G.E., **D.T. Booth** and J.W. Waggoner. 1990. Grazing reclaimed mined land seeded to native grasses in Wyoming. *Journal of Soil and Water Conservation* 45:653-657. **Booth, D.T.** 1989. Seedbed ecology of winterfat: Cations in diaspore bracts and their effect on germination and early plant growth. *Journal of Range* *Management*42:178-182. **Booth, D.T.** 1988. Winterfat diaspore morphology. *Journal of Range Management* 41:351-337. Griffith, L.W. and **D.T. Booth**. 1988. Indian ricegrass seed damage and germination responses to mechanical treatments. *Journal of Range Management* 41:351-337. **Booth, D.T.** 1985. The role of Fourwing Saltbush in mine land reclamation: A viewpoint.*Journal of Range Management* 38:562-565. **Booth, D.T.**1984. Threshing damage to radicle apex affects geotrophic response of winterfat. *Journal of Range Management* 37:222-225. **Booth, D.T.** 1984. Innovation in wildland shrub establishment. *Minerals and the Environment* 6:111-114. **Booth, D.T.** and L.W. Griffth.1984. Evaluation of air threshing for small lots of winterfat fruits. *Journal of Range Management*37:286-287. **Booth, D.T.,** and G.E. Schuman. 1983. Seedbed ecology of winterfat: Fruits versus threshed seeds. *Journal of Range Management* 36:387-390. Schuman, G.E., F. Rauzi and **D.T. Booth**. 1982. Production and competition of crested wheatgrass-native grass mixtures. *Agronomy Journal* 74:23-26.Stearns, M.M. and **D.T. Booth**. 1980.  Note on the quality characteristics of Indian Ricegrass (Wye). *Cereal Chemistry* 57:438-439. **Booth, D.T.**1980.  Emergence of bitterbrush seedlings on land disturbed by phosphate mining. *Journal of Range Management* 33:439-441. **Booth**, **D.T.,** C.G. Howard, and C.E. Mowry. 1980. ‘Nezpar’ Indian ricegrass: description, justification for release, and recommendations for use. *Rangelands* 2:53-54. McDole, R.E. and **D.T. Booth**. 1979. Fertilization of seedings on range and disturbed lands. *Current Information Series No. 513*, Cooperative Extension Service, University of Idaho, Moscow, ID 83843. **** **Dr. Richard Hart - Rangeland Scientist**
Richard H. "Dick" Hart was born in Iowa in 1933, attended country schools through 8th grade, and graduated from Villisca (Iowa) High School in 1950 as valedictorian of his class.  He earned a BS in Agronomy from Iowa State in 1954, then spent two years in the US Army.  He then earned an MS in Agronomy from Iowa State (1958) and a PhD in Crop Science from Oregon State in 1961.    He worked as Research Agronomist for University of Georgia in 1961 and 1962 at the Coastal Plain Experiment Station in TIfton, GA.  He then transferred to USDA-ARS as Research Agronomist, still at TIfton.  In 1966 he transferred to the Plant Industry Station of USDA-ARS at Beltsville, MD, still as Research Agronomist.  In 1974, he transferred to the newly-named High Plains Grasslands Research Station at Cheyenne, WY, first as Research Agronomist, then as Rangeland Scientist.  He retired from ARS in 2001.    Dick was honored with the Chapline Research Award of the Society for Range Management in 1992.  He was named a Fellow of the American Society of Agronomy in 1994 and of  SRM.  His research accomplish-ments, documented in 311 publications from abstracts to book chapters (list attached), include: 1) Quantified the role of hay yields and weather in the drying rate and quality of bermudagrass hay;2) Determined the effect of self-feeding supplemental corn or molasses on gains of steers grazing orchard-grass pasture;3) Quantified the effect of grazing pressure and forage production on cattle gains on pasture and rangeland;4) Incorporated these effects and cattle prices in the STEERISK and HEIFRISK computer models to determine the most profitable stocking rate on rangeland;5) Determined that rotation grazing systems did not improve cattle gains and range condition;6) Showed that 40 years of moderate grazing of shortgrass rangeland improved plant biodiversity;7) Used journals of early Western travellers and explorers to demonstrate that bison often grazed rangeland more heavily and persistently than domestic livestock, resulting in range conditions little different from those at present.    Dick served as advisor to 28 graduate students at University of Wyoming, Colorado State University, and University of Colorado.  He was invited as guest lecturer at these universities and University of Nebraska, Kansas State University, Louisiana State University, Texas Tech University, and Texas A & M University.    In addition to his research-related activities, Dick has presented over 100 performances as Theodore Roosevelt, and published two books of cowboy and country poetry, Rhymes of a Rexall Wrangler and Return of the Rexall Wrangler. Return to top of the page Hart, R.H., and E.F. Balla. 1982. Forage production and removal from western and crested wheatgrasses under grazing.  Journal of Range Management 35:362-366. Hart, R.H., 1983.  Correcting for salivary contamination of esophageal fistula samples.  Journal of Range Management  36:119-120. Hart, R.H., J.W. Waggoner Jr., D.H. Clark, C.C. Kaltenbach, J.A. Hager, and M.B. Marshall. 1983.  Beef cattle performance on crested wheatgrass plus native range vs. native range alone.  Journal of Range Management  36:38-40. Hart, R.H., E.F. Balla, and J.W. Waggoner Jr., 1983.  Gains of steers and calves grazing crested wheatgrass.  Journal of Range Management  36:483-484. Stroud, D.O., R.H. Hart, M.J. Samuel, and J.D. Rodgers. 1985.  Western wheatgrass responses to simulated grazing.  Journal of Range Management  38:103-108. Hart, R.H., and M.J. Samuel. 1985. Precipitation, soils, and herbage production on Southeastern Wyoming range sites.  Journal of Range Management 39:522-525. Hart, R.H., and J.G. Dean. 1986. Forage establishment: weather effects on stubble vs. fallow and fall vs. spring seeding.  Journal of Range Management  39:228-230. Abdel-Magid, A.H., M.J. Trlica and R.H. Hart. 1987.  Soil and vegetation responses to simu-lated trampling.  Journal of Range Management  40:303-306. Hart, R.H., M.J. Samuel, P.S. Test, and M.A. Smith. 1988. Cattle, vegetation and economic responses to grazing systems and grazing pressure.  Journal of Range Management  41:282-286. Hart, R.H., J.W. Waggoner Jr., T.G. Dunn, C.C. Kaltenbach, and L.D. Adams. 1988. Optimal stocking rate for cow-calf enterprises on native range and complementary improved pastures.  Journal of Range Management  41:435-441. Hart, R.H., 1989.  SMART: a Simple Model to Assess Range Technology.  Journal of Range Management  42:421-424. Hart, R.H., 1991.  Managing livestock grazing for risk: the STEERISK spread sheet. Journal of Range Management  44:227-231. Hepworth, K.W., P.S. Test, R.H. Hart, M.A. Smith, and J.W. Waggoner Jr., 1991.  Grazing systems, stocking rates, and cattle behavior in southeastern Wyoming.  Journal of Range Management  44:259-262. Samuel, M.J., and R.H. Hart. 1992.  Survival and growth of blue grama seedlings in competition with western wheatgrass.  Journal of Range Management  45:444-448. Hart, R.H., 1993.  Viewpoint: "Invisible colleges" and citation clusters in stocking rate research.  Journal of Range Management  46: 378-382. Hart, R.H., S. Clapp and P.S. Test. 1993.  Grazing strategies, stocking rates, and frequency and intensity of grazing on western wheatgrass and blue grama.  Journal of Range Management  46:122-126. Hart, R.H., J. Bissio, M.J. Samuel, and J.W. Waggoner Jr., 1993.  Grazing systems, pasture size, and cattle grazing behavior, distribution and gains.  Journal Range Management  46:81-87. Samuel, M.J., and R.H. Hart. 1994.  Sixty-one years of secondary succession on rangelands of the Wyoming High Plains.  Journal of Range Management  47:184-191. Hart, R.H., M.C. Shoop and M.M. Ashby. 1995. Nitrogen and atrazine on shortgrass: vegetation, cattle and economic responses. Journal of Range Management  48:165-171 Samuel, M.J., and R.H. Hart. 1995.  Observations on spread and fragmentation of blue grama clones in disturbed rangeland.  Journal of Range Management  48:508-510. Manley, W.A., R.H. Hart, M.J. Samuel, M.A. Smith, J.W. Waggoner Jr., and J.T. Manley. 1997. Cattle, vegetation and economic responses to grazing strategies and pressures.  Journal of Range Management  50: 638-646. Hart, R.H., and M.M. Ashby. 1998.  Grazing intensities, vegetation, and heifer gains: 55 years on shortgrass.  Journal of Range Management  51:392-398. Samuel, M.J., and R.H. Hart.1998.  Nitrogen fertilization, botanical composition and biomass production on mixed-grass rangeland.  Journal of Range Management  51:408-416. Cibils, A.F., D.M. Swift, and R.H. Hart.2001.  Gender-related differences of shrubs in stands of Atriplex canescens with different histories of grazing by cattle.  J. Arid Environ. 46:383-396. Hart, R.H., 2001.  Plant biodiversity on shortgrass steppe after 55 years of zero, light, moderate, or heavy cattle grazing. Plant Ecology 155(1):109-116. Cibils, A.F., D.M. Swift, and R.H. Hart., 2003.  Changes in shrub fecundity in fourwing saltbush browsed by cattle.  Journal of Range Management  56:39-46. Cibils, A.F., D.M. Swift, and R.H. Hart. 2003.  Female-biased herbivory in fourwing saltbush browsed by cattle.  Journal of Range Management  56:47-51. Hart, R.H., and W.A. Laycock. 1996. Repeat photography on range and forest lands in the western United States. Journal of Range Management  49:60-67. Schuman, G.E., J.D. Reeder, J.T. Manley, R.H. Hart, and W.A. Manley. 1999. Impact of grazing management on the carbon and nitrogen balance of a mixed-grass rangeland.  Ecol. Appl. 9:65-71. Abdel-Magid, A.H., G.E. Schuman and R.H. Hart.1987.  Soil bulk density and water infiltra-tion as affected by three grazing systems. Journal of Range Management  40:307-309. Bailey, D.W., L.W. Rittenhouse, R.H. Hart, and R.W. Richards. 1989.  Characteristics of spatial memory in cattle.  Appl. Animal Beh. Sci. 23:331-340. LeCain, D.R., J.A. Morgan, G.E. Schuman, J.D. Reeder, and R.H. Hart. 2002. Carbon exchange and species composition of grazed pastures and exclosures in the shortgrass steppe of Colorado.  Agriculture, Ecosystems, and Environment 93:421-435. Dr. Gerald Schuman- Soil Scientist stationed at the High Plains Grassland Research Station from 1978 - 2005.
A native of Wyoming, Jerry received his B.S. in Agriculture (Soil Science) at the University of Wyoming in June, 1966; an M.S. in Soil Chemistry in January, 1969 at the University of Nevada-Reno; and a Ph.D. in Agronomy (Soil Science) in May, 1974 at the University of Nebraska.  Dr. Schuman was stationed at ARS labs in Reno, Nevada (1966-1968); Lincoln, Nebraska (1969-1975) and Cheyenne, Wyoming (1975-2005), where he served as Research Leader from 1977-1998.
Jerry soil sampling (left) Return to top of page Howard, G.S., G.E. Schuman, and F. Rauzi. 1977.  Growth of Selected Plants on Wyoming Surface-Mined Soils and Flyash. Journal of Range Management 30 (4) Abdel-Mgid, Ahmed H., Gerald E. Schuman, and Richard H. Hart. 1985. Soil Bulk Density and Water Infiltration as Affected by Grazing Systems. Journal of Range Management 40 (4). Griffith, L.W.,  G.E. Schuman, F. Rauzi, and R.E. Baumgartner. 1984. Mechanical Renovation of Shortgrass Prairie for Increased Herbage Production. Journal of Range Management 38(1) Pinchik,B.A., G.E. Schuman, and E.J. Depuit. 1985. Topsoil and Mulch Effects on Plant Species and Community Responses of Revegetated Mined Land. Journal of Range Management 38(3) Schuman, G.E., E.M. Taylor, JR., and F. Rauzi. 1991. Forage production of reclaimed mined lands as influenced by nitrogen fertilization and mulching practice. Journal of Range Management 44(4) Schuman, G.E.,  E.J. Depuit, and K.M. Roadifer. 1994. Plant responses to gypsum amendment of sodic bentonite mine spoil. Journal of Range Management 47:206-209. Reeder,J.D., G.E. Schuman, R.A. Bowman. 1998. Soil C and N changes on conservation reserve program lands in the Central Great Plains. Soil & Tillage Research 47 339?349. Schuman, G.E., D.T. Booth, and J.R. Cockrell. 1998. Cultural methods for establishing Wyoming big sagebrush on mined lands. Journal Range Management 51:223-230. Schuman, G.E., J.D. Reeder, J. T. Manley, R. H. Hart, and W. A. Manley. 1999. Impact of grazing management on the carbon and Nitrogen balance of a mixed-grass rangeland. Ecological Appliccations, 9(1):65-71. Lecain, Daniel R., Jack A. Morgan, Gerald E. Schuman, Jean D. Reeder, And Richard H. Hart. 2000. Carbon exchange rates in grazed and ungrazed pastures of Wyoming. Journal Range Management 53:199-206 LeCain,Daniel R.,  Jack A. Morgan, Gerald E. Schuman,Jean D. Reeder, Richard H. Hart. 2002. Carbon exchange and species composition of grazed pastures and exclosures in the shortgrass steppe of Colorado. Agriculture, Ecosystems and Environment, 93:421-435 Reeder, J.D.,  G.E. Schuman. 2002. Influence of livestock grazing on C sequestration in semi-arid mixedgrass and short-grass rangelands. Environmental Pollution 116: 457-463 Schuman, G.E.,  H.H. Janzen, J.E. Herrick. 2002. Soil carbon dynamics and potential carbon sequestration by rangelands. Environmental Pollution 116: 391-396 Skinner, R. Howard,  Jon D. Hanson, Gordon L. Hutchinson, and Gerald E. Schuman. 2002. Response of C3 and Cq grasses to supplemental summer precipitation.Journal Range Management 55: 517-522 Williams, Mary I., Gerald E. Schuman, Ann L. Hild, and Laurel E. Vicklund. 2002.  Wyoming Big Sagebrush Density: Effects of Seeding Rates and Grass Competition. Restoration Ecology, 10:2:385-391 Mortenson, Matthew C., Gerald E. Schuman, and Lachlan J. Ingram. 2004. Carbon Sequestration in Rangelands Interseeded with Yellow-Flowering Alfalfa (Medicago sativa ssp.falcata). Environmental Management, 33:1: S475-S481 Reeder, Jean D., Gerald E. Schuman, Jack A. Morgan, Daniel R. Lecain. 2004. Response of Organic and Inorganic Carbon and Nitrogen to Long-Term Grazing of the Shortgrass Steppe. Environmental Management, 33:4:485-495. Derner, Justin D., Gerald E. Schuman, Michael Jawson,Steven R. Shafer, Jack A. Morgan, H. Wayne Polley, G. Brett Runion, Stephen A. Prior, H. Allen Torbert, Hugo H. Rogers, James Bunce, Lewis Ziska, Jeffrey W. White, Alan J. Franzluebbers, Jean D. Reeder, Rodney T. Venterea, and Lowry A. Harper. 2005. USDA-ARS Global Change Research on Rangelands and Pasturelands.  Rangelands  36-42. Ganjegunte, Girisha K., George F. Vance, Caroline M. Preston, Gerald E. Schuman, Lachlan J. Ingram, Peter D. Stahl, and Jeffrey M. Welker. 2005. Soil Organic Carbon Composition in a Northern Mixed-Grass Prairie: Effects of Grazing. Soil Science Society American Journal 69:1746-1756 Ingram, Lachlan J.  Gerald E. Schuman, Peter D. Stahl, and Lowell K. Spackman. 2005. Microbial Respiration and Organic Carbon Indicate Nutrient Cycling Recovery in Reclaimed Soils. Soil Science Society American Journal 69:1737-1745 Liebig, M.A.,  J.A. Morgan, .D. Reeder, B.H. Ellert, H.T. Gollany, G.E. Schuman. 2005. Greenhouse gas contributions and mitigation potential of agricultural practices in northwestern USA and western Canada. Soil & Tillage Research 83 25-52. Mortenson, Matthew C., Gerald E. Schuman, Lachlan J. Ingram,Venerand Nayigihugu, and Bret W. Hess. 2005. Forage Production and Quality of a Mixed-Grass Rangeland Interseeded With Medicago sativa ssp. falcata. Rangeland Ecol Manage 58:505-513. Schuman, Gerald E.,  Laurel E. Vicklund and Scott E. Belden. 2005. Establishing Artemisia tridentata ssp. wyomingensis on Mined Lands: Science and Economics. Arid Land Research and Management, 19:353-362 Bowen, C. K.,  G. E. Schuman, R. A. Olson, L. J. Ingram. 2005. Influence of Topsoil Depth on Plant and Soil Attributes of 24-Year Old Reclaimed Mined Lands. Arid Land Research and Management, 19:267-284 Herrick, Jeffrey E., Gerald E. Schuman, Albert Rango. 2006. Monitoring ecological processes for restoration projects. Journal for Nature Conservation 14: 161-171 Hild, Ann L., Gerald E. Schuman, Laurel E. Vicklund, and Mary I. Williams. 2006. Canopy Growth and Density of Wyoming Big Sagebrush Sown with Cool-Season Perennial Grasses. Arid Land Research and Management, 20:183-194 Derner, J.D.  and G.E. Schuman. 2007. Carbon sequestration and rangelands: A synthesis of land management and precipitation effects. Journal of Soil and Water Conservation,  62:2:77-85. Derner, Justin D., Hess, Bret W., Olson, Richard A. and Schuman, Gerald E. (2008) 'Functional Group and Species Responses to Precipitation in Three Semi-Arid Rangeland Ecosystems', Arid Land Research and Management, 22:1:81 - 92 Ingram, L. J., G. E. Schuman, J. S. Buyer, G. F. Vance, G. K. Ganjegunte, J. M. Welker, J. D. Derner. Grazing Impacts on Soil Carbon and Microbial Communities in a Mixed-Grass Ecosystem. Soil Science Society American Journal, 72:939-948 Svejcar, Tony, Raymond Angell, James A. Bradford, William Dugas, William Emmerich,Albert B. Frank, Tagir Gilmanov, Marshall Haferkamp, Douglas A. Johnson, Herman Mayeux, Pat Mielnick, Jack Morgan, Nicanor Z. Saliendra, Gerald E. Schuman, Phillip L. Sims, and Kereith Snyder. 2008. Carbon Fluxes on North American Rangelands. Rangeland Ecologcial Management 61:465-474. Schuman, G.E., L.J. Ingram, P.D. Stahl, J.D. Derner, G.F. Vance, and J.A. Morgan. 2009. Influence of Management on Soil Organic Carbon Dynamics in Northern Mixed-Grass Rangeland. Soil Carbon Sequestration and the Greenhouse Effect, 2nd edition. SSSA Special Publication 57:11:169-180. Borchgrevink, Matt B., Derner, Justin D., Weston, Terrill R., Olson, Richard A., Schuman, Gerald E. and Hess, Bret W.(2010) Small Mammal and Plant Community Responses to Mechanical Disturbance and Rest in Wyoming Big Sagebrush Grassland, Arid Land Research and Management, 24:1:57- 67. Schuman, Gerald E., Olson, Richard A., Partlow, Kristene A. andBelden, Scott E.(2010) Wildlife Impacts to Big Sagebrush on Reclaimed Mined Lands, Arid Land Research and Management, 24: 2:117 - 132  Dr. Jean Reeder- Soil Scientist Return to top of the page Justin D. Derner, Gerald E. Schuman, Michael Jawson,Steven R. Shafer, Jack A. Morgan, H. Wayne Polley, G. Brett Runion, Stephen A. Prior, H. Allen Torbert, Hugo H. Rogers, James Bunce, Lewis Ziska, Jeffrey W. White, Alan J. Franzluebbers, Jean D. Reeder, Rodney T. Venterea, and Lowry A. Harper. 2005. USDA-ARS Global Change Research on Rangelands and Pasturelands.  Rangelands, 36-42. Jean D. Reeder, Gerald E. Schuman, Jack A. Morgan, Daniel R. Lecain. 2004. Response of Organic and Inorganic Carbon and Nitrogen to Long-Term Grazing of the Shortgrass Steppe. Environmental Management, 33:4:485-495. Reeder, J.D., G.E. Schuman, J.A. Morgan and D.R. LeCain. 2004. Response of organic and inorganic carbon and nitrogen stocks to long-term grazing of the shortgrass steppe.  Environmental Management 33:485-495. Melinda A. Wheeler, M.J. Trlica, Gary W. Frasier and J.D. Reeder. 2002. Seasonal grazing affects soil physical properties of a montane riparian community. Journal of Range Management, 55: 49-56 Daniel R. LeCain, Jack A. Morgan, Gerald E. Schuman,Jean D. Reeder, Richard H. Hart. 2002. Carbon exchange and species composition of grazed pastures and exclosures in the shortgrass steppe of Colorado. Agriculture, Ecosystems and Environment 93: 421-435 J.D. Reeder, G.E. Schuman. 2002. Influence of livestock grazing on C sequestration in semi-arid mixedgrass and short-grass rangelands. Environmental Pollution 116: 457-463 Derner, J.D., D.T. Booth, J.A. Morgan, G.E. Schuman and J.D. Reeder.  2002. High Plains Grasslands Research Station - Changing to meet the challenges of a new century. Cow Country 130:4-5 Reeder, J.D., G.E. Schuman, J.A. Morgan, D.R. LeCain and R.H. Hart. 2001. Impact of grazing management strategies on carbon sequestration in a semi-arid rangeland, USA. Proceedings of the XIX International Grassland Congress. pp 211-213. Brazilian Society of Animal Husbandry, Sao Pedro, Sao Paulo, Brazil. XIX International Grassland Congress Schuman, G.E., D.R. LeCain, J.D. Reeder, and J.A. Morgan. 2001. Carbon dynamics and sequestration of a mixed-grass prairie as influenced by grazing. pp. 67-75. In: R. Lal (ed.)Soil Carbon Sequestration and the Greenhouse Effect. Soil Sci. Soc. Am., Special Publ. No. 57. Soil Science Society of America, Madison, WI LeCain, D.R., J.A. Morgan, G.E. Schuman, J.D. Reeder, and R.H. Hart. 2000. Carbon exchange rates in grazed and ungrazed pastures of Wyoming. Journal of  Range Management. 53: 199-206. Daniel R. Lecain, Jack A. Morgan, Gerald E. Schuman, Jean D. Reeder, And Richard H. Hart. 2000. Carbon exchange rates in grazed and ungrazed pastures of Wyoming. Journal of Range Management 53:199-206 G.E. Schuman, J.D. Reeder, J. T. Manley, R. H. Hart, and W. A. Manley. 1999. Impact of grazing management on the carbon and Nitrogen balance of a mixed-grass rangeland. Ecological Appliccations 9:1:65-71. J.D. Reeder, G.E. Schuman, R.A. Bowman. 1998. Soil C and N changes on conservation reserve program lands in the Central Great Plains. Soil & Tillage Research, 47: 339?349. J.D. Reeder and W.J. McGinnies. 1989. Response of established forages on reclaimed mined land to fertilizer N and P. Journal of Range Management. 42(4):327 -232 Dr. Merle Fairbourn Merle l. Fairbourn. 1980. The grass tetany potential of some Wyoming forages. Research Journal of University of Wyoming. Merle L. Fairbourn.  Irrugated annula forages for hay on the high plains.  Research Journal of University of Wyoming. Dr. Gary Fraiser
Hydraulic Engineer
1990-2001 RRRU
1992-2001 Scientist in charge of the CPER site. A.M. Wilson, R.L. Cuany,  J.G. Fraser and W.R. Oaks. 1981. Relationships among components of seed yield in Blue Grama.  Agronomy Journal, v.73 p1058-1062.  Marilyn Samuels - Worked with several scientist on rangeland health. Recieved several awards from SRM. Worked at HPGRS in the 1970's and 1980's. Samuel, M. J., and R. H. Hart.1998.  Nitrogen fertilization, botanical composition and biomass production on mixed-grass rangeland.  Journal of Range Management, 51:408-416. Samuel, M. J., and R. H. Hart. 1995.  Observations on spread and fragmentation of blue grama clones in disturbed rangeland.  Journal of Range Management, 48:508-510. Manley, W. A., R. H. Hart, M. J. Samuel, M. A. Smith, J. W. Waggoner Jr., and J. T. Manley. 1997. Cattle, vegetation and economic responses to grazing strategies and pressures. Journal of Range Management, 50: 638-646. Hart, R. H., J. Bissio, M. J. Samuel, and J. W. Waggoner Jr., 1993.  Grazing systems, pasture size, and cattle grazing behavior, distribution and gains.  JJournal of Range Management, 46:81-87. Samuel, M. J., and R. H. Hart. 1994.  Sixty-one years of secondary succession on rangelands of the Wyoming High Plains.  Journal of Range Management, 47:184-191. Samuel, M. J., and R. H. Hart. 1992.  Survival and growth of blue grama seedlings in competition with western wheatgrass.  Journal of Range Management, 45:444-448. Hart, R. H., M. J. Samuel, P. S. Test, and M. A. Smith. 1988. Cattle, vegetation and economic responses to grazing systems and grazing pressure.  Journal of Range Management, 41:282-286 Stroud, D. O., R. H. Hart, M. J. Samuel, and J. D. Rodgers. 1985.  Western wheatgrass responses to simulated grazing.  Journal of Range Management, 38:103-108. Hart, R. H., and M. J. Samuel. 1985. Precipitation, soils, and herbage production on Southeastern Wyoming range sites.  Journal of Range Management, 39:522-525. M.J. Samuel, F.Rauzi, and R.H. Hart. 1980. Nitrogen Fertilization of Range: Yield, Protein Content, and Cattle Behavior. Journal of Range Management, V33 # 2, p. 119-121.  Dr. John Dean  Dr. Larry Woods L.E. Woods, C.V. Cole, L.K. Porter and D.C. Coleman. 1987. Transformations of added and indigenous nitrogen in gnotobiotin soil: a comment on the priming effect. Soil Biology Biochem.  Vol. 19 #6, p.673-678. L.E. Woods and G.E.Schuman. 1986. Influence of Soil Organic Matter Concentrations on Carbon and Nitrogen Activity. The Soil Science Society of America Journal, V5 #5,p.1241-1245. Marvin Shoop M.C. Shoop, E.J. Alford, and H.F. Maryland. 1977. Plains Pricklypear is a good forage for cattle. V30 # 1, p 12-17. Marvin Shoop, G.P. Rupp, E.E.  Remmenga, P.J. Chenoweth, and L. Ball. 1978. Protein sources for Cattle wintered on Blue Grama Range. Proceedings of the First International Rangeland Congress, p 423 - 426. M.C. Shoop and D.N. Hyder. 1976. Growth of Replacement heifers on shortgrass ranges of Colorado. Journal of Range Management, v29#1, p4-8.  Gene Howard  D. Terrance Booth, Charles G. Howard and Charles E. Mowry. 1980. "Nezpar' Indian Ricegrass: Description, Justification For Release, and Recommendation for Use. Rangelands 2(2), p. 53-54. Gerald E. Schuman and Gene S. Howard. 1978.  Artemisia vulgaris L.: an ornamental plant for disturbed land reclamation. Journal of Range Management , v. 31 p 392-93.   Dr. William McGinnies William J. McGinnies. 1978. Thinning of Blue Grama Range for increased seed and forage production. Proceedings of the First International Rangeland Congress, p 645-646. William J. McGinnies and Alma M. Wilson. 1982. Using Blue Grama sod for Range Revegetation.  Journal of Range Management , v.35, p 259-261. William J. McGinnies and Jim R. Ludwig. 1978. Effects of Natrustoll Soil Horizons on germination, emergence, and growth four grasses.  Agronomy Journal ,v.70 p. 1086-1088.  Dr. Charlie Townsend - Agronomist - worked at the Crops Research Lab in Ft. Collins into the 1980's Return to top of page R.L Latterell and C.E. Townsend.  1982. Cytology and breeding behavior of cicer milkvetch. International Grassland Congress, p 174-176. C.E. Townsend.  1981. Breeding Cier Milkvetch for improved forage yield. Crop Science,  v 21 p 363-366.


Return to top


Connect with ARS Sign up


ARS Home
                            USDA.gov
                            Plain Writing
                            Policies & Links
                            Civil Rights Statements
                            FOIA
                            Accessibility Statement
                            Privacy Policy
                            Non-Discrimination Statement
                            Quality of Information
                            USA.gov
                            WhiteHouse.gov