Plant succession and biomass dynamics following logging and burning in Watersheds 1 and 3, Andrews Experimental Forest, 1962 to Present

  • Creator: C. Ted Dyrness, Charles B. Halpern
  • PI: Charles B. Halpern
  • Originator: C. Ted Dyrness
  • Other researchers: James A. Lutz, C. Ted Dyrness, Jerry F. Franklin
  • Dates of data collection: Jan 1 1962 - Jul 16 2019
  • Data collection status: Study continues and further data collection is planned
  • Data access: Online
  • DOI:
  • Last update: Aug 27 2020 (Version 16)
<Citation>     <Acknowledgement>     <Disclaimer>    
Dyrness, C.; Halpern, C. 2020. Plant succession and biomass dynamics following logging and burning in Watersheds 1 and 3, Andrews Experimental Forest, 1962 to Present. Long-Term Ecological Research. Forest Science Data Bank, Corvallis, OR. [Database]. Available: Accessed 2021-01-19.
Data were provided by the HJ Andrews Experimental Forest research program, funded by the National Science Foundation's Long-Term Ecological Research Program (DEB 1440409), US Forest Service Pacific Northwest Research Station, and Oregon State University.
While substantial efforts are made to ensure the accuracy of data and documentation, complete accuracy of data sets cannot be guaranteed. All data are made available "as is". The Andrews LTER shall not be liable for damages resulting from any use or misinterpretation of data sets.
There has been long history of geomorphic, hydrological, and ecological study in the experimental watersheds of HJA, which include WS1 and WS3 and the neighboring old-growth basin, WS2. These include comparative studies of sediment yield, stream chemistry, and water flow following whole-basin logging of WS1 and patch-cut logging of WS3, and long-term studies of post-harvest forest development. The latter, initiated in 1962, are among the longest-running and most intensive studies of secondary succession in forests of North America. They are based on two types of permanent plots (understory and overstory), spatially linked to facilitate analyses of overstory-understory interactions. Plots in WS1 and WS3 occur within transects within units of the watersheds. Understory quadrats were established in 1962, prior to harvest, and have been sampled periodically since the watersheds were cut and broadcast burned. They have been used to study how species’ life histories, pre-disturbance composition, disturbance intensity, and overstory development contribute to the long-term dynamics of the understory. These are 2 m by 2 m quadrats where canopy cover, ground conditions, growth forms, species cover and biomass have been monitored. Overstory tree plots were established nearly two decades later (1979-1980) to characterize the early stages of forest development, including the recruitment (ingrowth), growth, and mortality of conifers and hardwoods. These are circular plots (radius=8.92 m) where live trees greater than or equal to 1.37 m tall are measured for diameter at breast height or basal diameter. Remeasurement of these plots occurs on 5 or 6 year intervals.

Study Description Study Site Map Taxonomic Hierarchy Download Study Location Information: (CSV)
Download Full Documentation: (PDF)(EML)
1Watersheds 1 and 3 Succession Plots -- Plot descriptions: Vegetation and soil classifications with location, elevation, aspect and slope measurements (Jun 25 2002 - Jul 21 2013)METADATADATA
2WS1 & 3 Succession Plots -- Cover, frequency, and biomass measurement data (Sep 25 1979 - Oct 27 2017)METADATADATA
3WS1 & 3 Succession Plots -- Tagged trees: Diameter data (Jun 13 1979 - Jul 16 2019)METADATADATA
4WS1 & 3 Succession Plots -- Tagged trees: Height data (Jun 21 1979 - Sep 11 1979)METADATADATA
5WS1 & 3 Succession Plots -- Canopy closure (Jun 25 1990 - Feb 27 2017)METADATADATA
6Reference trees for plot center re-location (Jun 27 2017 - Oct 27 2017)METADATADATA

 Plot Layout - Plot and subplot layout for sampling post 1978.
 Tree Sampling Protocol - Tree remeasurement procedures (modified for 2007)
 Vegetation Sampling Protocol - Long-term vegetation succession plots sampling procedures (modified for 2008)

 Long-term growth, mortality and regeneration of trees in permanent vegetation plots in the Pacific Northwest, 1910 to present (TV010)
 Species interactions during succession in the western Cascade Range of Oregon, 1990 to present (TP103)
 Post-logging community structure and biomass accumulation in Watershed 10, Andrews Experimental Forest , 1974 to present (TP041)
 Ecosystem dynamics in a mature (Hagan block) and old-growth (Watershed 2) forest, Andrews Experimental Forest, 1981 to present (TP091)
 Plant biomass dynamics following logging, burning, and thinning in Watersheds 6 and 7, Andrews Experimental Forest, 1979 to present (TP114)
 Plant biomass dynamics in old-growth Watersheds 8 and 9 at the Andrews Experimental Forest, 2003 to present (TP115)

 Halpern, C.B., Lutz, J.A. 2013, Canopy closure exerts weak controls on understory dynamics: A 30-year study of overstory-understory interactions (Pub. No: 4786)
 Dovciak, Martin, Halpern, Charles B. 2010, Positive diversity-stability relationships in forest herb populations during four decades of community assembly (Pub. No: 4578)
 Lutz, James A., Halpern, Charles B. 2006, Tree mortality during early forest development: a long-term study of rates, causes, and consequences (Pub. No: 4017)
 Lutz, James A. 2005, The contribution of mortality to early coniferous forest development (Pub. No: 3931)
 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 (Pub. No: 2824)
 Halpern, Charles B., Spies, Thomas A. 1995, Plant species diversity in natural and managed forests of the Pacific Northwest (Pub. No: 1526)
 Halpern, Charles B., Franklin, Jerry F., McKee, Arthur 1992, Changes in plant species diversity after harvest of Douglas-fir forests (Pub. No: 1405)
 Halpern, Charles B., Franklin, Jerry F. 1990, Physiognomic development of Pseudotsuga forests in relation to initial structure and disturbance intensity (Pub. No: 1129)
 Halpern, Charles B. 1989, Early successional patterns of forest species: interactions of life history traits and disturbance (Pub. No: 956)
 Halpern, Charles B. 1988, Early successional pathways and the resistance and resilience of forest communities (Pub. No: 764)
 Dyrness, C. T. 1973, Early stages of plant succession following logging and burning in the western Cascades of Oregon (Pub. No: 429)
 Dyrness, C. T. 1969, Hydrologic properties of soils on three small watersheds in the western Cascades of Oregon (Pub. No: 372)
 Rothacher, Jack, Dyrness, C. T., Fredriksen, Richard L. 1967, Hydrologic and related characteristics of three small watersheds in the Oregon Cascades (Pub. No: 344)