LEMMA Team Detail
 | Matthew Gregory GIS Analyst/Programmer Dept. of Forest Ecosystems and Society Oregon State University | Mailing address: Department of Forest Ecosystems & Society Phone:Oregon State University 321 Richardson Hall Corvallis, OR 97331 (541) 758-7778 Email: |
Educational Background
B.A., 1993 (mathematics), The Colorado College, Colorado Springs, CO
M.S., 1999 (geographic techniques), Oregon State University, Corvallis, OR
Research Interests
Geographic visualization; regional scale vegetation mapping; discrete global grid systems
Biography
Matt has been working with the LEMMA team as a GIS analyst/programmer and database administrator since 1998. His roles include creating customized software for vegetation modeling and visualization, web and graphic design, spatial analysis and working with forest inventory data. More broadly, his interests lie at the intersection of geography, ecology and technology. Outside of work, Matt enjoys spending time with his family as well as soccer, carpentry, hiking and road trips.
Refereed Publications
 | Ohmann, JL, MJ Gregory, HM Roberts, WB Cohen, RE Kennedy, Z Yang. 2012. Mapping change of older forest with nearest-neighbor imputation and Landsat time-series. Forest Ecology and Management 272:13-25. |
| Ohmann, JL, MJ Gregory, EB Henderson, HM Roberts. 2011. Mapping gradients of community composition with nearest-neighbour imputation: extending plot data for landscape analysis. Journal of Vegetation Science 22(4):660-676. |
| Pierce Jr., KB, JL Ohmann, MC Wimberly, MJ Gregory, JS Fried. 2009. Mapping wildland fuels and forest structure for land management: a comparison of nearest-neighbor imputation and other methods. Canadian Journal of Forest Research 39(10):1901-1916. |
 | Gregory, MJ, A Kimerling, D White, K Sahr. 2008. A comparison of intercell metrics on discrete global grid systems. Computers, Environment and Urban Systems 32(3):188-203. |
| Kennedy, RSH, TA Spies, MJ Gregory. 2008. Relationships of dead wood patterns with biophysical characteristics and ownership according to scale in Coastal Oregon, USA. Landscape Ecology 23(1):55-68. |
| Ohmann, JL, MJ Gregory, TA Spies. 2007. Influence of environment, disturbance, and ownership on forest vegetation of Coastal Oregon. Ecological Applications 17(1):18-33. |
| Turner, DP, S Ollinger, ML Smith, O Krankina, MJ Gregory. 2004. Scaling net primary production to a MODIS footprint in support of Earth Observing System product validation. International Journal of Remote Sensing 25(10):1961-1979. |
| Turner, DP, S Urbanski, D Bremer, SC Wofsy, T Meyers, ST Gower, MJ Gregory. 2003. A cross-biome comparison of light use efficiency for gross primary production. Global Change Biology 9(3):383-395. |
| Ohmann, JL, MJ Gregory. 2002. Predictive mapping of forest composition and structure with direct gradient analysis and nearest-neighbor imputation in coastal Oregon, USA. Canadian Journal of Forest Research 32(4):725-741. |
| Turner, DP, ST Gower, WB Cohen, MJ Gregory, TK Maiersperger. 2002. Effects of spatial variability in light use efficiency on satellite-based NPP monitoring. Remote Sensing of Environment 80(3):397-405. |
Peer-Reviewed Publications
| Moeur, M, JL Ohmann, RE Kennedy, WB Cohen, Z Yang, MJ Gregory, HM Roberts, M Fiorella. 2011. Northwest Forest Plan -- status and trends of late-successional and old-growth forests from 1994 to 2008. PNW-GTR-853, Pacific Northwest Research Station, USDA Forest Service, Portland, OR. |
Technical Reports
| Grossmann, EB, JL Ohmann, J Kagan, HK May, MJ Gregory. 2010. Mapping ecological systems with a random forest model: tradeoffs between errors and bias. USGS Gap Analysis Bulletin, No. 17; February 2010; pp 16-22. |
| Grossmann, EB, JL Ohmann, MJ Gregory, HK May. 2009. Nationwide Forest Imputation Study (NaFIS) - Western Team final report. Final Report of the Nationwide Forest Imputation Study (NaFIS). |
| Grossmann, EB, J Kagan, JL Ohmann, HK May, MJ Gregory, C Tobalske. 2008. Final report on land cover mapping methods, map zones 2 and 7, Pacific Northwest ReGAP. Institute for Natural Resources, Oregon State University, Corvallis, OR. |
| Kagan, J, JL Ohmann, MJ Gregory, C Tobalske. 2008. Land cover map for map zones 8 and 9 developed from SAGEMAP, GNN, and SWReGAP: A pilot for NWGAP. USGS Gap Analysis Bulletin, No. 15; February 2008; pp 15-19. |
| Ohmann, JL, MJ Gregory, TM Holt. 2007. Innovative, 3-D, interactive, and immersive techniques for visualizing, querying, and understanding regional maps of forest vegetation, fuels, and fire risk. Final Report to the Governing Board, Joint Fire Science Program, Project 05-4-1-12. |
| Kagan, J, JL Ohmann, MJ Gregory, C Tobalske, JC Hak, JS Fried. 2006. Final report on land cover mapping methods, map zones 8 and 9, Pacific Northwest ReGAP. Institute for Natural Resources, Oregon State University, Corvallis, OR. |
| Ohmann, JL, MC Wimberly, JS Fried, KB Pierce Jr., MJ Gregory. 2005. A novel approach to regional fuel mapping: linking inventory plots with satellite imagery and GIS databases using the Gradient Nearest Neighbor method. Final report to the Governing Board, Joint Fire Science Program; Project 01-1-4-09. |
Other Non-Refereed Publications
| Holt, TM, MJ Gregory, JL Ohmann. 2007. GNNViz User Guide. Appendix 1 of the JFSP Final Report; Project 05-4-1-12. |
| Wimberly, MC, JL Ohmann, KB Pierce Jr., MJ Gregory, JS Fried. 2003. A multivariate approach to mapping forest vegetation and fuels using GIS databases, satellite imagery, and forest inventory plots. Proceedings of the Second International Wildland Fire Ecology and Fire Management Congress. Orlando, FL; 16-20 November 2003. American Meteorological Society. |
Presentations
 | Gregory, MJ, JL Ohmann, HM Roberts, HSJ Zald, EB Henderson. 2013. Recent advances and applications of nearest neighbors methods for regional-scale forest vegetation mapping in the Pacific Northwest, USA. Landcare Research Seminar: Lincoln, New Zealand; February 2013. |
| Henderson, EB, JL Ohmann, MJ Gregory, HM Roberts, HSJ Zald. 2012. All for one or one for all? Mapping many species individually versus simultaneously with random forest. Ecological Society of America Annual Conference: Portland, OR; August 2012. |
| Ohmann, JL, MJ Gregory, HM Roberts, RE Kennedy, Z Yang, J Braaten, SL Powell, WB Cohen, V Kane, J Lutz. 2012. Mapping change in live and dead forest biomass with Landsat time-series, remeasured plots, and nearest-neighbor imputation. ForestSat 2012: Corvallis, OR; September 2012. |
| Powell, SL, RE Kennedy, JL Ohmann, WB Cohen, MJ Gregory, HM Roberts, V Kane, J Lutz. 2012. Comparison of biomass allometric approaches for regional scale carbon mapping. ForestSat 2012: Corvallis, OR; September 2012. |
| Ohmann, JL, MJ Gregory, HM Roberts, RE Kennedy, WB Cohen, Z Yang, M Moeur. 2011. Spatial monitoring of older forest and habitat for the Northwest Forest Plan. National FIA Users Group Meeting: Sacramento, CA; March 2011. |
| Ohmann, JL, MJ Gregory, HM Roberts, RE Kennedy, Z Yang, M Moeur, WB Cohen. 2011. Landscape context for density management: implications of land ownership and ecological gradients. Conference on state-of-the-art in west-side forest management: Corvallis, OR; October 2011. |
| Gregory, MJ, EB Grossmann, JL Ohmann, HM Roberts. 2010. The Nationwide Forest Imputation Study (NaFIS): Challenges, results and recommendations from the western United States. Forest Inventory and Analysis Science Symposium: Knoxville, TN; October 2010. |
| Ohmann, JL, MJ Gregory, HK May, EB Grossmann. 2010. Nearest neighbor mapping of vegetation gradients for landscape analysis and planning. 53rd International Symposium of the International Association for Vegetation Science: Ensenada, Mexico; April 2010. |
| Ohmann, JL, MJ Gregory, HM Roberts, RE Kennedy, WB Cohen, Z Yang, M Moeur. 2010. Spatial monitoring of late-successional forest habitat over large regions with nearest-neighbor imputation. XXIII International Union of Forest Research Organizations (IUFRO): Seoul, South Korea; August 2010. |
| Grossmann, EB, JL Ohmann, MJ Gregory, HK May. 2009. Gradients or hierarchies? Which assumptions make a better map?. US Regional Association of the International Association of Landscape Ecology Annual Meeting: Snowbird, UT; April 2009. |
| Grossmann, EB, JL Ohmann, MJ Gregory, HK May. 2009. Regional vegetation mapping: Making sense of the methods. Workshop on remote sensing for land managers: Redding, CA; June 2009. |
| Grossmann, EB, JL Ohmann, MJ Gregory, HK May. 2009. Bringing our best data into conservation and restoration planning. California Klamath-Siskiyou Fire Learning Network Workshop: Weaverville, CA; July 2009. |
| Grossmann, EB, JL Ohmann, MJ Gregory, HK May. 2009. Regional vegetation - methods behind the maps: Gradient Nearest Neighbor and random forest modeling. Information Sharing Workshop, Bureau of Land Management: Salem, OR; April 2009. |
| Gregory, MJ, JL Ohmann, EB Grossmann, HK May. 2008. Spatial scaling effects of inventory reference data on nearest neighbor model predictions. Forest Inventory and Analysis Symposium: Park City, UT; October 2008. |
| Gregory, MJ, JL Ohmann, HK May, EB Grossmann, KB Pierce Jr., TM Holt, JS Fried. 2008. Recent advances and applications of nearest neighbors methods for regional-scale forest vegetation modeling. Department of Forest Science Seminar: Corvallis, OR; April 2008. |
| Gregory, MJ, JL Ohmann, TM Holt. 2008. GNNViz: Immersive and collaborative visualization for landscapes. The Nature Conservancy Climate Change Workshop: Portland, OR; April 2008. |
| Gregory, MJ, JL Ohmann, TM Holt. 2008. Seeing data with GIS: from paper maps to immersive visualizations. Kids Keynote address to GIS Day: Corvallis, OR; November 2008. |
| Grossmann, EB, JL Ohmann, J Kagan, KB Pierce Jr., HK May, MJ Gregory. 2008. Random forests and nearest neighbors: Methods for mapping the West Cascades of Oregon. US Regional Association of the International Association of Landscape Ecology Annual Meeting: Madison, WI; April 2008. |
| Grossmann, EB, JL Ohmann, MJ Gregory, HK May. 2008. Is the World a Gradient, or a Hierarchy of Thresholds? Imputing Forest Composition and Structure Variables in the Pacific Northwest. Forest Inventory and Analysis Symposium: Park City, UT; October 2008. |
| Ohmann, JL, M Moeur, M Hemstrom, T Burcsu, J Merzenich, MJ Gregory, HK May, EB Grossmann. 2008. Integrating forest inventory data, vegetation maps, and models of vegetation dynamics to support landscape analysis and planning: the IMAP story. Forest Inventory and Analysis Symposium: Park City, UT; October 2008. |
| Ohmann, JL, MJ Gregory, HK May, EB Grossmann. 2008. Gradient Nearest Neighbor (GNN) maps of forest vegetation: accuracy assessment and uncertainty. Interagency Mapping and Assessment Project (IMAP) Users' Group: Portland, OR; February 2008. | |
| Grossmann, EB, JL Ohmann, J Kagan, KB Pierce Jr., HK May, MJ Gregory. 2007. Models for ecological systems map building: random forest and gradient nearest neighbor. Which one works best?. National GAP Analysis Program Conference: Asheville, NC; September 2007. |
| Ohmann, JL, KB Pierce Jr., EB Grossmann, MJ Gregory, HK May, TM Holt. 2007. Current Vegetation Mapping in Western Oregon. Presented at: USFS Klamath Falls Ranger District: Klamath Falls, OR; June 2007. |
| Ohmann, JL, MJ Gregory, KB Pierce Jr., HK May, EB Grossmann. 2007. Seeing the forest and the trees: harnessing GIS to map forests of the Pacific Northwest. Keynote address to GIS Day: Corvallis, OR; November 2007. |
| Gregory, MJ. 2006. Mapping current vegetation in the Pacific Coast states with Gradient Nearest Neighbor imputation. Department of Forest Science Remote Sensing Seminar: Corvallis, OR; October 2006. | |
| Gregory, MJ, JL Ohmann, BC McComb. 2006. Sensitivity of wildlife habitat capability models to spatial resolution of underlying mapped vegetation data. 2006 Nearest Neighbors Workshop - Meeting in the Middle: Minneapolis, MN; August 2006. |
| Ohmann, JL, JS Fried, KB Pierce Jr., MJ Gregory, MC Wimberly. 2006. Mapping forest vegetation and fuels with Gradient Nearest Neighbor imputation. Yosemite Fire Science Symposium: Yosemite National Park, CA; May 2006. |
| Ohmann, JL, KB Pierce Jr., EB Grossmann, MJ Gregory, HK May, TM Holt. 2006. Mapping current vegetation in the Pacific Coast States with GNN, CART, and other tricks. Workshop and field tour with NF, ODF, TNC, and R6: Sycan Marsh Research Station, OR; September 2006. |
| Ohmann, JL, MJ Gregory, KB Pierce Jr., TM Holt, HK May. 2006. Mapping forest species and plant communities with Gradient Nearest Neighbor imputation. 2006 Nearest Neighbors Workshop - Meeting in the Middle: Minneapolis, MN; August 2006. |
| Fried, JS, JL Ohmann, KB Pierce Jr., MC Wimberly, MJ Gregory. 2005. A mid-scale approach to mapping forest fuel and fire hazards at the wildland-urban interface by imputation and modeling of inventory plot data. Seventh Annual Forest Inventory and Analysis Science Symposium: Portland, ME; October 2005. | |
| Gregory, MJ, KB Pierce Jr., JL Ohmann. 2005. Gradient Nearest Neighbor imputation for local scale basal area mapping: FIA 2005 Symposium interpolation contest. Seventh Annual Forest Inventory and Analysis Science Symposium: Portland, ME; October 2005. |
| Ohmann, JL, KB Pierce Jr., MJ Gregory, JS Fried. 2005. Gradient Nearest Neighbor imputation based on FIA plots - useful tool or lying with maps?. Seminar at Forestry Sciences Lab: Portland, OR; August 2005. | |
| Pierce Jr., KB, JL Ohmann, MJ Gregory, JS Fried. 2005. Regional vegetation mapping in support of risk assessment. Workshop on regional risk assessment methodologies. Organized by Western Wildlands Environmental Threat Assessment Center, USDA Forest Service: Portland, OR; September 2005. | |
| Pierce Jr., KB, JL Ohmann, MJ Gregory, JS Fried. 2005. Gradient Nearest Neighbor imputation mapping in support of risk assessment. Workshop for evaluating quantitative techniques for deriving national scale data for assessing and mapping risk; organized by Forest Health Technology Enterprise Team, Forest Health Protection, USDA Forest Service: Fort Collins, CO; July 2005. | |
| Pierce Jr., KB, MC Wimberly, JL Ohmann, MJ Gregory, JS Fried. 2005. What is the probability that I-30 runs through Fort Worth? Incorporating uncertainty into map use. Annual meeting of the Society of American Foresters: Fort Worth, TX; October 2005. | |
| Gregory, MJ, A Kimerling, D White, K Sahr. 2004. Evaluating desirable geometric characteristics of discrete global grid systems : revisiting the Goodchild criteria. Second International Conference on Discrete Global Grids: Ashland, OR; October 2004. |
| Ohmann, JL, KB Pierce Jr., MJ Gregory, MC Wimberly, JS Fried. 2004. A novel approach to regional fuel mapping: linking inventory plots with satellite imagery and GIS databases using the Gradient Nearest Neighbor method. Joint Fire Science Program Principal Investigator Workshop: Phoenix, AZ; April 2004. | |
| Pierce Jr., KB, JL Ohmann, MJ Gregory. 2004. Assessing spatial uncertainty in landscape vegetation maps created with imputation procedures. US Regional Association of the International Association of Landscape Ecology Annual Meeting: Las Vegas, NV; April 2004. | |
| Wimberly, MC, C Avery, JL Ohmann, KB Pierce Jr., MJ Gregory, JS Fried. 2004. Influences of landscape structure, drought, and wind on crown fire spread in forest landscapes. US Regional Association of the International Association of Landscape Ecology Annual Meeting: Las Vegas, NV; April 2004. | |
| Ohmann, JL, KB Pierce Jr., MJ Gregory, MC Wimberly, JS Fried. 2003. A novel approach to regional fuel mapping: linking inventory plots with satellite imagery and GIS databases using the Gradient Nearest Neighbor method. Joint Fire Science Program Principal Investigator Workshop: Phoenix, AZ; March 2003. | |
| Ohmann, JL, KB Pierce Jr., MJ Gregory, S Danskin, MC Wimberly, JS Fried. 2003. Mapping live and dead forest fuels at the ecoregion scale in coastal Oregon with Landsat imagery and forest inventory plots. US Regional Association of the International Association of Landscape Ecology Annual Meeting: Banff, AB; April 2003. | |
| Ohmann, JL, MJ Gregory, TA Spies. 2003. Linking field plot, satellite imagery, and environmental data to assess regional patterns of vegetation biodiversity. Annual meeting of the Society of American Foresters: Buffalo, NY; October 2003. | |
| Ohmann, JL, MJ Gregory, TA Spies. 2003. Predictive vegetation mapping and current vegetation biodiversity in coastal Oregon. Botany and Plant Pathology Departmental seminar: Corvallis, OR; February 2003. | |
| Wimberly, MC, JL Ohmann, KB Pierce Jr., MJ Gregory, JS Fried. 2003. A multivariate approach to mapping forest vegetation and fuels using GIS databases, satellite imagery, and forest inventory plots. Fifth Symposium on Fire and Forest Meteorology and 2nd International Wildland Fire Ecology and Fire Management Congress: Orlando, FL; November 2003. | |
| Ohmann, JL, MJ Gregory. 2002. Predictive mapping of forest composition and structure with direct gradient analysis and nearest-neighbor imputation (the Gradient Nearest Neighbor method). Focus session at the Joint Meeting of Fourth Annual Forest Inventory and Analysis Science Symposium and the Southern Forest Mensurationists: New Orleans, LA; November 2002. | |
| Ohmann, JL, TA Spies, MJ Gregory, KN Johnson. 2002. Vegetation biodiversity in coastal Oregon forests. A Multi-ownership Assessment of Forests and Watersheds of the Oregon Coast Range. Presented as part of an all-day symposium and workshop of invited stakeholders and landowners. Organized by the Coastal Landscape Analysis and Modeling Study (CLAMS): Corvallis, OR; June 2002. | |
| Gregory, MJ, A Kimerling, D White, K Sahr. 2000. Comparing intercell distance and cell wall midpoint criteria for discrete global grid systems. First International Conference on Discrete Global Grids: Santa Barbara, CA; March 2000. |
| Gregory, MJ, JL Ohmann. 2000. Predictive mapping of forest composition and structure using the Gradient Nearest Neighbor Method. Willamette Valley GIS Users Group: Corvallis, OR; November 2000. | |
| Ohmann, JL, MJ Gregory, JE Gray. 1999. Linking satellite, plot, and environmental data to map patterns of species composition across Pacific Northwest forests. Special session at annual meeting of the American Society of Photogrammetry and Remote Sensing: Portland, OR; May 1999. |
Posters
| Ohmann, JL, MJ Gregory, HM Roberts, RE Kennedy, WB Cohen, Z Yang, M Moeur, M Fiorella. 2012. Mapping change of older forest with permanent plots, Landsat time series, and nearest-neighbor imputation. Ecological Society of America Annual Conference: Portland, OR; August 2012. |
| Roberts, HM, JL Ohmann, MJ Gregory, EB Henderson. 2012. Gradient nearest neighbor forest vegetation maps for landscape analysis and planning. ForestSat 2012: Corvallis, OR; September 2012. |
| Zald, HSJ, JL Ohmann, HM Roberts, R McGaughey, MJ Gregory, RE Kennedy. 2012. Influence of inventory plot and Landsat imagery positional accuracies on nearest-neighbor (NN) imputation maps of vegetation composition and structure. ForestSat 2012: Corvallis, OR; September 2012. |
| Gregory, MJ, JL Ohmann, HM Roberts, R Riemann. 2011. Nearest neighbor vegetation maps for landscape analysis and conservation planning: are they good enough, and how will I know?. US Regional Association of the International Association of Landscape Ecology Annual Meeting: Portland, OR; April 2011. |
| Ohmann, JL, MJ Gregory, HM Roberts, RE Kennedy, WB Cohen, Z Yang, M Moeur, M Fiorella. 2011. Spatial monitoring of forest landscape dynamics with permanent plots, Landsat time-series and nearest-neighbor imputation. US Regional Association of the International Association of Landscape Ecology Annual Meeting: Portland, OR; April 2011. |
| Roberts, HM, JL Ohmann, MJ Gregory, EB Henderson. 2011. Gradient nearest neighbor forest vegetation maps for landscape analysis and planning. US Regional Association of the International Association of Landscape Ecology Annual Meeting: Portland, OR; April 2011. |
| Roberts, HM, JL Ohmann, MJ Gregory, EB Grossmann. 2010. Nearest-neighbor forest vegetation maps from FIA plots and geospatial data for landscape analysis and planning in the Pacific Northwest (and beyond). Forest Inventory and Analysis Symposium: Knoxville, TN; October 2010. |
| Grossmann, EB, JL Ohmann, HK May, MJ Gregory. 2009. Mapping mountain hemlock and pinpointing ponderosa pine: Imputation mapping species distributions in Western Oregon. North American Forest Ecology Workshop: Logan, UT; June 2009. |
| Ohmann, JL, MJ Gregory, HK May, EB Grossmann, RE Kennedy, WB Cohen, Z Yang, E Pfaff, M Moeur. 2009. Spatial monitoring of disturbance and late-succesional forest dynamics in the Pacific Northwest. US Regional Association of the International Association of Landscape Ecology Annual Meeting: Snowbird, UT; April 2009. |
| Gregory, MJ, JL Ohmann, TM Holt. 2008. An application of computer gaming technology to visualize, query, and understand forest landscapes. US Regional Association of the International Association of Landscape Ecology Annual Meeting: Madison, WI; April 2008. |
| Grossmann, EB, JL Ohmann, J Kagan, MJ Gregory, HK May. 2008. Context-dependent hierarchy of plant community predictors from the Oregon Coast Range to the eastern slopes of the Cascade Mountains. Ecological Society of America Annual Meeting: Milwaukee, WI; August 2008. |
| Ohmann, JL, MJ Gregory, JD Kline, RJ Alig, HK May, EB Grossmann. 2008. Implications of social and ecological gradients for conservation planning in large, multi-ownership, forested landscapes. US Regional Association of the International Association of Landscape Ecology Annual Meeting: Madison, WI; April 2008. |
| Grossmann, EB, JL Ohmann, J Kagan, KB Pierce Jr., HK May, MJ Gregory. 2007. A tale of two techniques: Gradient Nearest Neighbor and random forest for mapping ecological systems in Oregon's Western Cascades. North American Forest Ecology Workshop: Vancouver, BC; June 2007. |
| Fried, JS, JL Ohmann, MC Wimberly, KB Pierce Jr., MJ Gregory. 2006. Tapping the forest inventory for spatially continuous estimates of fuels and fire potential: the GNNFire approach. First Fire Behavior and Fuels Conference: Fuels Management - how to measure success: Portland, OR; March 2006. | |
| Ohmann, JL, MJ Gregory, KB Pierce Jr., MC Wimberly, JS Fried. 2005. A novel approach to regional fuel mapping: linking inventory plots with satellite imagery and GIS databases using the Gradient Nearest Neighbor method. Poster presented at Joint Fire Science Program Principal Investigator Workshop: San Diego, CA; November 2005. | |
| Ohmann, JL, MJ Gregory, KB Pierce Jr., MC Wimberly, JS Fried. 2005. Mapping forest vegetation and fuels with Gradient Nearest Neighbor imputation in three western ecoregions. JFSP Annual Meeting: San Diego, CA; October 2005. |
| Gregory, MJ, JL Ohmann. 2004. Spatial modeling of regional vegetation using field plots and geospatial information: a software framework for the Gradient Nearest Neighbor method. College of Forestry Spatial Data Management Group: Corvallis, OR; April 2004. |
| Gregory, MJ, JL Ohmann. 2004. Spatial modeling of regional vegetation using field plots and geospatial information: a software framework for the Gradient Nearest Neighbor method. US Regional Association of the International Association of Landscape Ecology Annual Meeting: Las Vegas, NV; April 2004. |
| Pierce Jr., KB, JL Ohmann, MJ Gregory, MC Wimberly, JS Fried. 2004. Mapping forests of the Pacific Northwest: structure, species and uncertainty. Ecological Society of America Annual Meeting: Portland, OR; August 2004. |
| Wimberly, MC, C Avery, JL Ohmann, KB Pierce Jr., MJ Gregory, JS Fried. 2004. Landscape connectivity and the potential for catastrophic fire in forested landscapes. Ecological Society of America Annual Meeting: Portland, OR; August 2004. | |
| Hicks, WT, ME Harmon, JL Ohmann, MJ Gregory, B McCune, SD Berryman, E Martin, L Geiser. 2003. Mapping the abundance and activity of two symbiotic nitrogen fixers in western Oregon. North American Forest Ecology Workshop: Corvallis, OR; June 2003. | |
| Ohmann, JL, TA Spies, MJ Gregory, KN Johnson. 2003. Distribution of vegetation biodiversity across a continuum of land ownership and management emphasis in coastal Oregon. North American Forest Ecology Workshop: Corvallis, OR; June 2003. |
| Ohmann, JL, TA Spies, MJ Gregory, KN Johnson. 2002. Distribution of vegetation biodiversity across a continuum of land ownership and management emphasis in coastal Oregon. US Regional Association of the International Association of Landscape Ecology Annual Meeting: Lincoln, NE; April 2002. |
| Turner, DP, S Ollinger, ML Smith, O Krankina, MJ Gregory. 2002. Scaling net primary production to a MODIS footprint in support of Earth Observing System product validation. Ecological Society of America Annual Meeting: Tucson, AZ; August 2002. | |
| Hudak, AT, MJ Gregory, JL Ohmann, M Moeur, MA Lefsky, WB Cohen. 2001. Comparison of two methods for mapping forest structure from inventory plot and environmental data in Western Oregon. US Regional Association of the International Association of Landscape Ecology Annual Meeting: Tempe, AZ; April 2001. | |
| Ohmann, JL, MJ Gregory. 2001. How does spatial resolution affect Gradient Nearest Neighbor vegetation maps?. Symposium: A landmark assessment of Oregon's forest sustainability: Corvallis, OR; October 2001. | |
| Ohmann, JL, MJ Gregory. 2001. How does spatial resolution affect Gradient Nearest Neighbor vegetation maps?. US Regional Association of the International Association of Landscape Ecology: Tempe, AZ; April 2001. | |
| Ohmann, JL, MJ Gregory. 2001. Predictive mapping of forest composition and structure using direct gradient analysis and nearest-neighbor imputation. North American Forest Ecology Workshop: Duluth, MN; June 2001. | |
| Ohmann, JL, MJ Gregory. 2001. Predictive mapping of forest composition and structure using direct gradient analysis and nearest-neighbor imputation. Symposium: A landmark assessment of Oregon's forest sustainability: Corvallis, OR; October 2001. | |
| Turner, DP, ST Gower, SC Wofsy, AK Knapp, T Meyers, MJ Gregory. 2001. A cross-biome comparison of vegetation light use efficiency. Global Change Open Science Conference: Amsterdam, Netherlands; June 2001. | |
| Hudak, AT, MJ Gregory, JL Ohmann, M Moeur, MA Lefsky, WB Cohen. 2000. Predictive mapping of tree species basal areas from forest inventory and environmental data: a comparison of two models. Ecological Society of America Annual Meeting: Snowbird, UT; August 2000. |
| Ohmann, JL, MJ Gregory. 2000. Predictive mapping of forest composition and structure using direct gradient analysis and nearest-neighbor imputation. Ecological Society of America Annual Meeting: Snowbird, UT; August 2000. | |
| Turner, DP, ST Gower, WB Cohen, MJ Gregory, TK Maiersperger. 2000. Spatial heterogeneity in vegetation light use efficiency over an agricultural landscape in central Illinois. Ecological Society of America Annual Meeting: Snowbird, UT; August 2000. | |
| Ohmann, JL, MJ Gregory. 1999. A Nearest Neighbor Method for Mapping Forest Composition in the Oregon Coastal Province. Oregon's Forests at the Millennium: What Might the Future Hold?: Corvallis, OR; September 1999. | |
| Turner, DP, MJ Gregory, BE Law, PM Anthoni, PE Thornton. 1999. Validating modeled gross primary production and evapotranspiration using eddy covariance flux measurements. Ecological Society of America Annual Meeting: Spokane, WA; August 1999. |