PSW Research Spotlight from July - September 2023
Effective beginning 5/30/2025
This website, and all linked websites under the control of the agency, is under review and content may change.
The publications below were posted from Pacific Southwest Research Station researchers between July 2023 and September 2023. There are many more publications produced by our scientists available through Treesearch.
Featured Publications
Hawaii & U.S. affiliated Pacific IslandsLandscape epidemiology of the spread of Rapid ʻŌhiʻa Death Photo Credit
Background imagery from Google Earth
Detection density maps for Hawaiʻi Island from each of the four GAO coverage campaigns, January 2016 (a), June-July 2017 (b), January 2018 (c), and January 2019 (d), with regions of higher map uncertainty masked out (shown in blue-filled polygons). |
| Ceratocystis lukuohia, a fungal pathogen that causes Rapid ʻŌhiʻa Death, has more than a million ʻōhiʻa (Metrosideros polymorpha), Hawaii's keystone native tree species, on Hawaiʻi Island. Researchers found that probability of C. lukuohia infection is greater for trees in closer proximity to previously infected trees. They also found that the severity of infection, or density of disease symptom detection, increased in relation to canopy height and exposure, windspeed, and drier conditions. Interestingly, trees on the youngest soils showed lower infection rates than trees on adjacent, older substrates. Researchers determined these of landscape-scale mortality patterns and dynamics in Hawaii's native forests by analyzing high-resolution remote sensing data of ʻōhiʻa canopies collected over four consecutive years with machine learning random forest models. The information shared in this paper can help land managers better predict, prepare for, and prevent the spread of C. lukuohia. |
Vaughn, Nicholas R.; Hughes, R. Flint; Asner, Gregory P. 2023. Multi-scale remote sensing-based landscape epidemiology of the spread of rapid hi a Death in Hawai'i. Forest Ecology and Management. 538: 120983. |
CaliforniaUsing culturally significant birds to guide the timing of prescribed fires Map of the Klamath Siskiyou Bioregion study area in northern California and southern Oregon showing locations and regional designations of 92 banding stations where adult birds were captured. Region abbreviations are: COAST, Coast; KLMTR, Klamath-Trinity; MENDO, Mendocino; MOUNT, Mountain; REDWD, Redwood; SISKI, Siskiyou. |
The Klamath Siskiyou Bioregion, covering Northern California and Southern Oregon, has a complex history with fire. Historically, there was a tradition of cultural burns in the area timed with indigenous traditional ecological knowledge, which often took ecosystem cycles into account in guiding their practices. Today, fire is starting to be reintroduced into the landscape after a long period of fire exclusion and suppression following colonization of the Western U.S. Prescribed burns are being introduced by forest managers working with federal, state, and local agency backing to help reduce fuel load and fire severity. Along the same vein, cultural burns are being reintroduced in indigenous communities, realigning with the culturally significant role fire plays in ecosystem management.
Since prescribed burns are often limited by the tools and resources of the treating agency, such as personnel, air quality risks, temperature, etc., they are often done outside of peak wildfire season, when the prescribing agency has more resources at their disposal. As a result, prescribed burns run the risk of overlapping with sensitive time periods for avian development, including mating and molting seasons in the area. By examining culturally significant bird species, and pairing traditional ecological knowledge, this work aims to reduce the risks to the wildlife ecosystem, while achieving the goal of successfully reintroducing fire to the region in a meaningful way. This study examines the feasibility of forest managers coordinating prescribed fire timing using real-world molting and breeding data from culturally significant species of birds in the region. |
Long, Linda L.; Lake, Frank L.; Stephens, Jaime L.; Alexander, John D.; Ralph, C. John; Wolfe, Jared D. 2023. Using culturally significant birds to guide the timing of prescribed fires in the Klamath Siskiyou Bioregion. Ecosphere. 14(6): e4541. |
General Technical Reports |
 Interventions to restore wildfire-altered forests in California
Long, Jonathan W.; Walsh, Dana; Coppoletta, Michelle; Tompkins, Ryan E.; Meyer, Marc D.; Isbell, Clint; Bohlman, Gabrielle N.; North, Malcolm P. 2023. Interventions to restore wildfire-altered forests in California. Gen. Tech. Rep. PSW-GTR-278. Albany, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station. 105 p.  Blueprint for resilience: the Tahoe-Central Sierra Initiative
Manley, Patricia N.; Povak, Nicholas A.; Wilson, Kristen N.; Fairweather, Mary Lou; Griffey, Vivian; Long, Linda L. 2023. Blueprint for resilience: the Tahoe-Central Sierra Initiative. Gen. Tech. Rep. PSW-GTR-277. Albany, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station. 94 p. |
Publications by Research Area |
