Pacific Northwest Resource Monitoring and Assessment (PNW-RMA) data help describe plant biodiversity in the region's forests, characteristics of special habitat types such as old-growth forests and riparian corridors, and status of forest components such as dead wood, tree crowns, soils, and understory vegetation.
Nonnative invasive plant species already are well established in Oregon's forested lands, making up a significant proportion of the species and plant cover present. Current trends suggest that their importance will increase.
- Changes in land use and housing on resource lands in Washington state, 1976-2006. - Gray, Andrew N.; Azuma, David L.; Lettman, Gary J.; Thompson, Joel L.; McKay, Neil. 2013
- Assessing the carbon consequences of western juniper (Juniperus occidentalis) encroachment across Oregon, USA. Rangeland Ecology and Management. 65(3): 223-231. - Campbell, John L.; Kennedy, Robert E.; Cohen, Warren B.; Miller, Richard F. 2012
- Canopy gaps affect long-term patterns of tree growth and mortality in mature and old-growth forests in the Pacific Northwest. Forest Ecology and Management. 281: 111-120. - Gray, Andrew N.; Spies, Thomas A.; Pabst, Robert J. 2012
- Forest inventory vegetation database of the United States of America. Biodiversity and Ecology 4: 225-231. - Gray, Andrew N., Thomas J. Brandeis, John D. Shaw, William H. McWilliams, and Patrick D. Miles 2012
- Epiphytic macrolichen community composition database - epiphytic lichen synusiae in forested areas of the US. Biodiversity and Ecology 4: 439-439. - Jovan, Sarah 2012
- Eutrophic lichens respond to multiple forms of N: implications for critical levels and critical loads research. Ecological Applications. 22(7): 1910-1922. - Jovan, Sarah; Riddell, Jennifer; Padgett, Pamela E; Nash, Thomas 2012
- Estimating canopy cover from standard forest inventory measurements in western Oregon. Forest Science. 58(2): 154-167. - McIntosh, Anne; Gray, Andrew; Garman, Steven 2012
- Regional distribution of introduced plant species in the forests of the northeastern corner of the United States. Potter, K.M.; Conkling, B.L., eds.. Draft Forest Health Monitoring 2011 National Technical Report, Version 1/20/2012. Washington, DC: U.S. Department of Agriculture, Forest Service, Forest Health Monitoring Program. 123 p. - Schulz, B.; Moser, W.K.; Olson, C; and Johnson, K. 2012
- Estimating habitat value using forest inventory data: the fisher (Martes pennanti) in northwestern California. Forest Ecology and Management 275: 35-42. - Zielinski, William J., Jeffrey R. Dunk, and Andrew N. Gray 2012
- Forests of southeast and south-central Alaska, 2004-2008: five-year forest inventory and analysis report. Gen. Tech. Rep. PNW-GTR-835. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 156 p. - Barrett, Tara M.; Christensen, Glenn A., tech. eds. 2011
- Potential of a national monitoring program for forests to assess change in high-latitude ecosystems. Biological Conservation. 144: 1285-1294. - Barrett, Tara M.; Gray, Andrew N. 2011
- Urban trees and the risk of poor birth outcomes. Health and Place. 17: 390-393 - Donovan, Geoffrey H.; Michael, Yvonne L.; Butry, David T.; Sullivan, Amy D.; Chase, John M. 2011
- Nonnative invasive plants of Pacific coast forests: a field guide for identification. Gen. Tech. Rep. PNW-GTR-817. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 91 p. - Gray, Andrew N.; Barndt, Katie; Reichard, Sarah H. 2011
- Quantifying ecological thresholds from response surfaces. Ecological Modeling. 222: 427-436 - Lintz, Heather E.; McCune, Bruce; Gray, Andrew N.; McCulloh, Katherine A. 2011
- Mapping gradients of community composition with nearest-neighbor imputation: extending plot data for landscape analysis. Journal of Vegetation Science 22: 660-676. - Ohmann, Janet L.; Gregory, Matthew J.; Henderson, Emilie B.; Roberts, Heather M. 2011
- Biological control reduces growth, and alters water relations of the saltcedar tree (Tamarix spp.) in western Nevada, USA. Journal of Arid Environments. 75: 346-685. - Pattison, R.R.; D'Antonio, C.M.; Dudley, T.L. 2011
Vegetation diversity and structure indicator
The Vegetation Diversity and Structure (VEG) Indicator is an extensive inventory of vascular plants in the forests of the United States. The VEG Indicator provides baseline data to assess trends in forest vascular plant species richness and composition, and the relative abundance and spatial distribution of those species, including invasive and introduced species. The VEG Indicator is one of several sets of measures collected by the Forest Inventory and Analysis (FIA) program of the USDA Forest Service to assess forest health. This document describes the sampling design, field data collection methods, primary output objectives, and estimation procedures for summarizing FIA VEG data.
Invasive plant distribution and abundance and associations with forest conditions and history. Nonnative plants affect the composition and function of natural and managed ecosystems. FIA and RMA researchers are working to provide more comprehensive information on the abundance, distribution, and impact of nonnative invasive species.
A field guide for identification of nonnative invasive plants of Pacific Coast forests. This publication provides a prioritized short list of the nonnative invasive plants having the greatest impact on forested lands in the Pacific coastal states (California, Oregon, and Washington).
This project entails predicting impacts from nitrogen pollution on forests through lichen monitoring. Epiphytic lichens (i.e. growing on woody plants) subsist almost exclusively on atmospheric moisture and nutrients, making them highly responsive to changes in air quality and forest structure and function.
Forest structure and function
Forests provide vital habitat for a wide variety of plant and animal species, and provide many other ecological values. Pacific Northwest Forest Inventory and Analysis (PNW-FIA) program data help describe plant biodiversity in Pacific Northwest forests, characteristics of special habitat types such as old-growth forests and riparian corridors, and status of forest components such as dead wood, tree crowns, soils, and understory vegetation. Specific projects include predicting tree distribution, growth, and mortality across large spatial and temporal scales.
National vegetation classification
Vegetation composition and structure of forested ecosystems are indicators of productivity, wildlife habitat, and ecosystem function. Classifications developed to distinguish and describe local vegetation conditions can provide interpretations that are relevant to managers of these resources. A major challenge in national vegetation classification development in the Western United States is bridging the gap between the floristically derived association levels with the mid-levels defined by both physiognomic and floristic characteristics. Data sets that encompass wider regions help to clarify how floristically driven levels relate to each other and higher levels in the classification.