USDA Forest Service

Pacific Southwest Research Station


Pacific Southwest Research Station
800 Buchanan Street
West Annex Building
Albany, CA 94710-0011

(510) 559-6300

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Science that makes a difference.

The Pacific Southwest Research Station is a world leader in natural resources research through our scientific excellence and responsiveness to the needs of current and future generations.

We represent the research and development branch of the USDA Forest Service in the states of California and Hawaii and the U.S. affiliated Pacific Islands. Our primary work occurs in California (the most populous state with the fifth largest economy in the world) and Hawaii (a strategic location in the Pacific Rim economies and tourism). Our mission is to develop and communicate science needed to sustain forest ecosystems and their benefits to society.

[image-text]: What's New

Smoke emissions from debris piles (background) with plastic covers (not shown) were measured in burning mixtures of wood and polyethylene plastic (foreground). The addition of the plastic to the burning wood had little to no effect on trace gas and particulate emissions. Photo credit: David Weise, USDA Forest Service) Study gives new perspective on agricultural plastic, debris burning, and air quality - To reduce fire hazard in the United States, wildland managers often utilize the silvicultural practice of mechanically cutting woody shrubs and suppressed trees (ladder fuels). These cuttings and other post-logging debris are then burned during periods of low fire danger in order to dispose of the material. To improve the burning and minimize hazardous air pollutants, managers often cover all or part of the debris pile with low-density polyethylene plastic, commonly referred to as agricultural plastic, in order to keep water out. A recent study published in the Journal of the Air and Water Association shows that inclusion of agricultural plastic in debris piles has no effect on smoke emissions. [Read the full news release at

This prescribed burn in maritime chaparral at Vandenberg Air Force Base demonstrates that describing the burning vegetation is critical to reliably predicting the impact of wildland fire on greenhouse gas emissions and black carbon. Photo credit: Joey Chong, USDA Forest ServiceState of wildland fire emissions, carbon, and climate research - Scientists know that wildland fire emissions play a significant role in the global carbon cycle and that its principal component – carbon dioxide – is a primary driver of climate change. But predicting and quantifying the effects of potential future emissions is a difficult process requiring the integration of complex interactions of climate, fire, and vegetation. The current state of knowledge, critical knowledge gaps, and importance of fire emissions for global climate and terrestrial carbon cycling is the focus of nine science syntheses published in a special issue in the Forest Ecology and Management journal titled, Wildland Fire Emissions, Carbon, and Climate: Science Overview and Knowledge Needs. [Read the full news release at

Female woodland salamander subject animal. Photo credit:  Garth Hodgson, USDA Forest ServicePredation on invertebrates by woodland salamanders increases carbon capture - Woodland salamanders perform a vital ecological service in American forests by helping to mitigate the impacts of global warming. Global warming occurs when greenhouse gases like carbon dioxide are released into the atmosphere. Woodland salamanders facilitate the capture of this carbon before it is released by feeding on invertebrates (beetles, earthworms, snails, ants, etc.) that would otherwise release carbon through consumption of fallen leaves and other forest debris. Woodland salamanders are the most common vertebrate species in American forests; consequently, these small, seldom-seen animals may play a significant role in regulating the capture of carbon from leaf litter in forest soils. [Read the full news release at]

From left to right, Flint Hughes, USDA Forest Service, and Rebecca Most, The Nature Conservancy, transport debris across the anchialine pool to a staging area where it will be chipped into mulch. Photo credit:  Mel Dean, USDA Forest ServicePSW’s Institute of Pacific Islands Forestry help restore ancient Hawaiian fishpond - Research station staff helped to restore an ancient Hawaiian Kīholo fishpond, which was once a vital food source and critical habitat for rare invertebrate species endemic to the Hawaiian Islands. Staff cleared debris from the pool perimeter to reduce nutrient loading caused by overhanging vegetation, as well as removed weeds and tended to native plants within a fenced unit that will be used as a nursery area for future restoration activities.

Learn more about the Institute of Pacific Islands Forestry on the Institute's program page.

Multi-lane freeway containing many cars is surrounded on both sides with roadside vegetation Integrating vegetation into sustainable transportation planning may benefit public health - In recent years, the health of people living, working, or going to school near roads with high traffic volume has been a rising national concern. Studies conducted in the United States and throughout the world have shown that air pollution levels are especially elevated near high-volume roadways. A multidisciplinary group of researchers, planners and policymakers recently gathered in Sacramento, Calif. to discuss roadside vegetation as a viable option for mitigating these adverse health impacts from air pollution. The group combined their key concerns and findings for an article in TR News magazine. [Read the full news release at]

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[image-text]: Recent Publications

Cover image psw-gtr-242Busse, Matt D.; Hubbert, Ken R.; Moghaddas, Emily E. Y. 2014. Fuel Reduction Practices and Their Effects on Soil Quality. Gen. Tech. Rep. PSW-GTR-241. Albany, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station. 156 p.

Cover image psw-gtr-244Pope, Karen; Brown, Catherine; Hayes, Marc; Green, Gregory; Macfarlane, Diane, tech. coords. 2014. Cascades frog conservation assessment. Gen. Tech. Rep. PSW-GTR-244. Albany, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station. 116 p.

Cover image psw-rp-266 Hugh D. Safford and Kip M. Van de Water. 2014. Using Fire Return Interval Departure (FRID) Analysis to Map Spatial and Temporal Changes in Fire Frequency on National Forest Lands in California. Res. Pap. PSW-RP-266. Albany, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station. 59 p.

[image-text]: Featured Science

Global Climate Change

Last Modified: Jul 21, 2014 03:35:38 PM