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Thirtieth anniversary of 1996 floods

News Brief Description: 

This weekend (Feb 6-8, 2026) marks the 30th anniversary of the major flood of 1996, which was one of the largest flows in the recorded history of Lookout Creek in the H.J. Andrews Experimental Forest (HJA). The flood caused damage and destruction to communities across the Northwest--at its peak, the Willamette River came within a foot of overtopping the walls and flooding downtown Portland, Oregon.  At the start of the storm over a foot of snow was at the HJA headquarters site and over the several days of the storm an additional foot of rain fell, melting the snow, feeding the flood.  Gordon Grant took video at several places in and near Andrews, and segments were incorporated in Alan Honick's video, Torrents of Change. Research following the flood showed dramatic change in characteristics of streams and riparian zones, but also amazing resilience of components of the stream ecosystem. Rain-on-snow floods like the 1996 event are the largest floods not just in the PNW, but nationally, and the Andrews Forest long-term data provides unique insights into what causes these floods. 

Debris flows on roads at the HJA Dec 2025

News Brief Description: 

Multiple debris flows occured at the HJ Andrews Experimental Forest this week, following heavy rains. On-site staff noted a few debris flows that had deposited trees and soil over roads. Travel on impacted roadways at the HJA will impossible until early 2026. At this point, headquarters has not been impacted and can be reached. Contact the Forest Director if you have plans to do field work in watersheds 9,10,1,2, or 3--which are beyond the impacted road sections.

MS Defense: “Douglas-fir and Western Hemlock Responses to Extreme Heat”

Event Date: 
Thursday, December 4, 2025
Event Brief Description: 

MS Defense. Gabby John. Dec 4 at 2 PM. “Douglas-fir and Western Hemlock Responses to Extreme Heat.” Co-advised by Drs. Chris Still and Mark Schulze, Gabby’s thesis project utilizes high-resolution microclimate and tree expansion data from the H.J. Andrews Experimental Forest to understand the extent to which the 2021 PNW Heat Dome affected tree growth. Peavy 125 and zoom.

Andrews Forest Monthly Meeting February 2025

Event Date: 
Friday, February 7, 2025
Event Brief Description: 

Andrews Forest Monthly Meeting: Friday, January 10,  9-11 AM

Presentations:

  • “Examining changing spatial patterns in forest canopy gap formation with landscape disturbance” presented David M Bell, Research Forester, USDA Forest Service PNW Research Station.
  • “Climate mediated increases in background mortality in temperate rainforests of the Pacific Northwest” presented by Ella Gray, Postdoctoral Scholar, FERM (w/ Dave Bell & Matt Powers)

After our presentations, at 10 AM, we will move into our community meeting, which includes updates on graduate student activities, site, WNF, community enhancement, education, new faces, and recent publications.

Peavy 315, Oregon State University.  Contact Lina DiGregorio for zoom option.

Our meetings follow the academic year. Upcoming meetings: Feb 7, Mar 7, April 4, May 2, June 6.

Watershed Responses to Disturbance

As climate change intensifies, natural disturbances are dramatically reshaping ecosystems. This is especially prevalent across the western United States, particularly in vulnerable mountain regions with complex landscapes and tightly linked land-water systems. In this study, we examine how disturbances—whether sudden events like wildfires and bark beetle outbreaks, or ongoing pressures like reduced snowpack and gradual vegetation changes—affect the chemistry and flow of streams in temperate montane watersheds.

Stream Chemistry Response to Fire

Wildfires are increasingly affecting the wet forests of the Pacific Northwest, a trend expected to intensify with climate change. These fires disrupt water quality and streamflow, threatening aquatic ecosystems and drinking water supplies. While the impacts of high-severity wildfires on streams are relatively well-studied, less is known about low- and mixed-severity fires. To address this, researchers studied the mixed-severity 2020 Holiday Farm Fire in two watersheds within the H.J. Andrews Experimental Forest.

Andrews Forest Monthly Meeting January 2025

Event Date: 
Friday, January 10, 2025
Event Brief Description: 

Andrews Forest Monthly Meeting: Friday, January 10,  9-11 AM

Presentations:

  • “NWFP amendment DEIS overview and introduction: how can HJA community engage in the process?” presented by Dr. Meg Krawchuk, Department of Forest Ecosystems and Society, College of Forestry OSU; serving member of Northwest Forest Plan Federal Advisory Committee.
  • “Streamflow generation in the heterogeneous subsurface landscape of the HJA: How will the landscape respond to fire?” Presenters: Zachary Perry and Dr. Catalina Segura, Department of Forest Ecosystems and Society, College of Forestry OSU
  • Graduate Student Lightning Talk: Title: “Water availability after fire: Modeling snowmelt isotopes in the HJA” presented by Lutz Klein, University of Bonn, Germany. Lutz is a first-year PhD student co-advised by Julian Klaus and Catalina Segura.
  • GlASS: Global Aggregation of Stream Silicon -- Shiny app with HJA data. Demonstration. Pamela Sullivan.
  • Lookout Fire Hypothesis paper update. Matt Betts and Dana Warren. 

After our presentations, at 10 AM, we will move into our community meeting, which includes updates on graduate student activities, site, WNF, community, education, new faces, and recent publications.

Peavy 315, Oregon State University.  Contact Lina DiGregorio for zoom option.

Our meetings follow the academic year. Upcoming meetings: Jan 10 (Peavy 315), Feb 7, Mar 7, April 4, May 2, June 6.

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