Robert Pabst


Program coordinator
Pacific Northwest Permanent Sample Plot Program

MSHpulse_2015-07-30 Rob Pabst on a little water and shade break.jpg

My research focuses on the long-term dynamics of forest processes. I serve as coordinator of the Pacific Northwest Permanent Sample Plot Program (PNW-PSP,, one of the longest-running research projects of its kind in the world, with tree measurements spanning decades to a century across a network of more than 140 permanent plots in Oregon and Washington. The program’s research objective is to understand the trends, patterns and mechanisms of tree growth, biomass accumulation, tree mortality and tree regeneration, as well as successional changes in forest understories. Many of our permanent plots are stem-mapped, allowing us to examine fine-scale spatial patterns of these processes. I also use simulation models to examine forest successional processes under different forest management regimes.

Selected publications

Acker, S.A., J.A. Kertis and R.J. Pabst. 2017. Tree regeneration, understory development, and biomass dynamics following wildfire in a mountain hemlock (Tsuga mertensiana) forest. Forest Ecology and Management 384: 72-82.

Harmon, M.E. and R.J. Pabst. 2015. Testing hypotheses of forest succession using long-term data: 100 years of observations in the Oregon Cascades. Journal of Vegetation Science 26(4): 722–732.

Pabst, R.J., Goslin, M.N., Garman, S.L., and Spies, T.A. 2008. Calibrating and testing a gap model for simulating forest management in the Oregon Coast Range. Forest Ecology and Management 256:958–972.

Pabst, R.J. and Spies, T.A. 2001. Ten years of vegetation succession on a debris-flow deposit in Oregon. Journal of the American Water Resources Association 37(6): 1693-1708.

Pabst, R.J. and Spies, T.A. 1999. Structure and composition of unmanaged riparian forests in the coastal mountains of Oregon, U.S.A. Canadian Journal of Forest Research 29: 1557-1573.

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