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Understanding the role of vegetation succession in forest ecosystems of the Pacific Northwest is a fundamental part of long-term ecological research at H.J. Andrews Experimental Forest. Studies in this component seek to understand how plant communities change in composition and structure over the course of succession and what processes control these changes. We are particularly interested in how changes in vegetation over the course of succession affect other ecosystem processes such as vegetation water-use, carbon storage, nitrogen cycling, and disturbance regimes. The research for this component primarily makes use of data from a large network of permanent study plots across a wide range of stand ages, habitats, management histories, and disturbance types in Oregon and Washington and data from long-term monitoring of experimental watersheds at the H.J. Andrews Experimental Forest. The long-term data from the permanent study plot program provides the only means of directly observing the relatively slow dynamics of Pacific Northwest forests. Mature, old-growth at HJA Reference Stand 12

Research Details

Key Databases

List of all Vegetation databases


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Key Citations

Stephenson, N. L.; Das, A. J.; Condit, R.; Russo, S. E.; Baker, P. J.; Beckman, N. G.; Coomes, D. A.; Lines, E. R.; Morris, W. K.; Ruger, N.; Alvarez, E.; Blundo, C.; Bunyavejchewin, S.; Chuyong, G.; Davies, S. J.; Duque, A.; Ewango, C. N.; Flores, O.; Franklin, J. F.; Grau, H. R.; Hao, Z.; Harmon, M. E.; Hubbell, S. P.; Kenfack, D.; Lin, Y.; Makana, J.-R.; Malizia, A.; Malizia, L. R.; Pabst, R. J.; Pongpattananurak, N.; Su, S.-H.; Sun, I-F.; Tan, S.; Thomas, D.; van Mantgem, P. J.; Wang, X.; Wiser, S. K.; Zavala, M. A. 2014. Rate of tree carbon accumulation increases continuously with tree size. Nature. 2014/01/15/online:1476-4687. doi:10.1038/nature12914. (Pub No: 4835)

Seidl, Rupert., Spies, Thomas A., Rammer, Werner., Steel, E. Ashley., Pabst, Robert. J., Olsen, Keith. 2012. Multi-scale Drivers of Spatial Variation in Old-Growth Forest Carbon Density Disentangled with Lidar and an Individual-Based Landscape Model. Ecosystems. Ecosystems 15:1321-1335. DOI: 10.1007/s10021-012-9587-2 (Pub No: 4792)

Seidl, Rupert; Rammer, Werner; Scheller, Robert M.; Spies, Thomas A. 2012. An individual-based process model to simulate landscape-scale forest ecosystem dynamics. Ecological Modelling. 231: 87-100. (Pub No: 4649)

Zald, Harold S. J.; Spies, Thomas A.; Huso, Manuela; Gatziolis, Demetrios. 2012. Climatic, landform, microtopographic, and overstory canopy controls of tree invasion in a subalpine meadow landscape, Oregon Cascades, USA. Landscape Ecology. 27:1197-1212. doi:10.1007/s10980-012-9774-8. (Pub No: 4662)

Azuma, David; Monleon, Vicente J. 2011. Differences in forest area classification based on tree tally from variable- and fixed-radius plots. Canadian Journal of Forest Research. 41: 211-214. (Pub No: 4731)

Lookingbill, Todd R.; Rocca, Monique E.; Urban, Dean L. 2011. Focused assessment of scale-dependent vegetation pattern. In: Drew, C. A.; Wiersman, Yolanda F.; Huettmann, Falk, eds. Predictive species and habitat modeling in landscape ecology: concepts and applications. Springer: 111-138. (Pub No: 4738)

Dovciak, Martin; Halpern, Charles B. 2010 . Positive diversity-stability relationships in forest herb populations during four decades of community assembly. Ecology Letters. 13: 1300-1309, doi:10.1111/j.1461-0248.2010.01524.x. (Pub No: 4578)

van Mantgem, Phillip J.; Stephenson, Nathan L.; Byrne, John C.; Daniels, Lori D.; Franklin, Jerry F.; Fulé, Peter Z.; Harmon, Mark E.; Larson, Andrew J.; Smith, Jeremy M.; Taylor, Alan H.; Veblen, Thomas T. 2009. Widespread increase of tree mortality rates in the western United States. Science. 323: 521-524 [plus supporting material]. (Pub No: 4479)

Harmon, Mark E.; Woodall, Christopher W.; Fasth, Becky; Sexton, Jay. 2008. Woody detritus density and density reduction factors for tree species in the United States: a synthesis. Gen. Tech. Rep. NRS-29 . Newton Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station. 84 p. (Pub No: 4300)

Jones, Chad C.; Halpern, Charles B.; Niederer, Jessica. 2008. Plant succession on gopher mounds in western Cascade meadows: consequences for species diversity and heterogeneity. American Midland Naturalist . 159: 275-286. (Pub No: 4251)

Takaoka, Sadao; Swanson, Frederick J. 2008. Change in extent of meadows and shrub fields in the central western Cascade Range, Oregon. Professional Geographer. 60(4): 1-14. (Pub No: 3847)

Woolley, Travis J.; Harmon, Mark E.; O'Connell, Kari B. 2007. Estimating annual bole biomass production using uncertainty analysis. Forest Ecology and Management. 253: 202-210. (Pub No: 4282)

Haugo, Ryan D.; Halpern, Charles B. 2007. Vegetation responses to conifer encroachment in a western Cascade meadow: a chronosequence approach. Canadian Journal of Botany. 85: 285-298. (Pub No: 4193)

Lang, Nicole L.; Halpern, Charles B. 2007 . The soil seed bank of a montane meadow: consequences of conifer encroachment and implications for restoration. Canadian Journal of Botany. 85: 557-569. (Pub No: 4239)

Sheehy, Samantha. 2006. Exotic plant species dynamics from 1994 to 2005 on road networks in forested landscapes of western Oregon. Corvallis, OR: Oregon State University. 236 p. M.S. thesis. (Pub No: 4158)

Lang, Nicole L. 2006. The soil seed bank of an Oregon montane meadow: consequences of conifer encroachment and implications for restoration. Seattle, WA: University of Washington. 58 p. M.S. thesis. (Pub No: 4173)

Griffiths, Robert; Madritch, Michael; Swanson, Alan. 2005. Conifer invasion of forest meadows transforms soil characteristics in the Pacific Northwest. Forest Ecology and Management. 208: 347-358. (Pub No: 3855)

Binkley, Dan. 2003. Seven decades of stand development in mixed and pure stands of conifers and nitrogen-fixing red alder. Canadian Journal of Forest Research. 33: 2274-2279. (Pub No: 3736)

Acker, S. A.; Halpern, C. B.; Harmon, M. E.; Dyrness, C. T. 2002. Trends in bole biomass accumulation, net primary production and tree mortality in Pseudotsuga menziesii forests of contrasting age. Tree Physiology. 22: 213-217. (Pub No: 2824)

Smithwick, Erica A. H.; Harmon, Mark E.; Remillard, Suzanne M.; Acker, Steven A.; Franklin, Jerry F. 2002. Potential upper bounds of carbon stores in forests of the Pacific Northwest. Ecological Applications. 12(5): 1303-1317. (Pub No: 2833)

Acker, Steven A.; Harcombe, Paul A.; Harmon, Mark E.; Greene, Sarah E. 2000. Biomass accumulation over the first 150 years in coastal Oregon Picea-Tsuga forest. Journal of Vegetation Science. 11: 725-738. (Pub No: 2382)

Acker, S. A.; McKee, W. A.; Harmon, M. E.; Franklin, J. F. Long-term research on forest dynamics in the Pacific Northwest: a network of permanent plots. In: Dallmeier, F.; Comisky, J. A., eds. Forest diversity in North, Central and South America: research and monitoring. Carnforth, Lancashire, UK: Man and the Biosphere Series Vol. 12, UNESCO and the Parthenon Publishing Group; 1998:93-107. (Pub No: 3557)