USDA Forest Service

Pacific Southwest Research Station

DEPAR TMENT OF AGRICULT UR

2012 Accomplishments Report E

Serving California, Hawai‘i, and the Pacific Islands

Sherri Eng
Vision and Mission

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. Our mission is to 

develop and communicate science needed 

to sustain forest ecosystems and their 

benefits to society.

About Us

The Pacific Southwest Research Station (PSW) represents Forest Service Research and 

Development in California, Hawai‘i, and the U.S.-affiliated Pacific Islands. Our region has the 

lowest, driest desert in the country, the highest elevations within the 48 contiguous States, and 

the wettest tropical forests. An abundant diversity of native plants and animals and nearly half of 

the nation's threatened and endangered species live in this region. At PSW, we develop and deliver 

science to help inform decisions about natural resource management, conservation, and 

environmental protection. Much of our work is accomplished in cooperation with other research 

and development institutions, such as universities, and state and other federal agencies.

Sherri Eng
I am extremely proud to 

present the Pacific 

Southwest Research 

Station's 2012 

Accomplishments Report. 

This has been an exciting, 

challenging, and very 

rewarding year for all of 

us at PSW. I was fortunate 

to be appointed as the 

permanent Station 

Director in 2012, and I am thrilled to officially join the 

high-performing team at PSW. I look forward to 

continuing to build on past successes as we focus our 

research efforts on critical issues impacting the 

public and our natural resources well into the future. 

The goal of the Forest Service's Research and 

Development programs is to improve lives by 

improving the connections between people, trees, 

and forest ecosystems. We're going to continue to 

ensure that our research remains relevant, and that we 

conduct rigorous science in an efficient and effective 

business environment that best serves our nation. 

To accomplish our goals, we must be mindful of the 

interactions among people, ecosystems, and myriad 

environmental changes. Human activities have an 

increasing impact on the functioning of our 

ecosystems and understanding the interplay 

between social dynamics and natural resources will 

be an increasing part of our work. We appreciate the 

unique and rich diversity of the peoples of California, 

Hawai’i, and the Pacific island states, and embrace 

the perspectives of our constituents as we shape our 

research programs to best serve their needs through 

inclusion and outreach. Key research emphasis areas 

for PSW include adapting to a changing climate; 

human cultures and natural resource stewardship; 

integrated fire ecology and management; 

conservation of at-risk species and communities; and 

sustainable energy and environmental impacts. 

More than 50 percent of California’s fresh water 

comes from National Forest Lands. In addition to 

supplying clean water for residential and industrial 

use, it also supports the approximately $37 billion in 

food and commodities produced in California’s 

agriculture economy. Nearly 20 percent of California 

is National Forest Lands that support 38,000 jobs. We 

are increasing our strong partnership with the 

National Forest System (NFS) in our region, investing 

in research that will assist land managers with new 

planning rules, developing and sustaining healthy 

and resilient forests in the face of change, 

contributing to accelerated restoration of our forests 

and grasslands, and providing clean, reliable water 

and other environmental infrastructure to sustain 

and enhance quality of life. 

We remain committed to serving the public through 

community service programs. Four that I am particularly 

proud of are mentioned in the pages that follow. Many of 

them are financially supported through grant programs, 

but equally importantly through the dedicated 

volunteers from PSW and their families who regularly 

give their time and energy to support these initiatives.

I am particularly excited about our prospects for the 

future at PSW. As we continue to refine our focus on 

our primary emphasis areas, we look forward to 

building out our capacity and capabilities across the 

station. A key contributor to our success is the 

development of our Hawai’i facility, the Institute of 

Pacific Island Tropical Forestry (IPIF). We will fill the 

Director’s position in Hilo, HI in FY13, and count this 

addition as a critical factor in supporting our research 

in Hawai’i and throughout the U.S.-affiliated states in 

the Pacific. The IPIF Director will supervise the 

scientists and support staff at IPIF and manage the 

Hawai’i Experimental Tropical Forest on the island of 

Hawai’i, and will work closely with our collaborators 

and partners in the state of Hawai’i and the Pacific 

region to sustain our viability and relevancy. 

The coming year poses many challenges and 

unknown outcomes with budget, policy, and 

environmental impacts on every facet of our work. At 

PSW, we look forward to the challenges that lie 

ahead, and work in concert with all of the Forest 

Service to better position ourselves to deliver 

innovative science to ensure environmental health 

and community stability throughout California, 

Hawai’i, and the U.S.-affiliated Pacific Islands. 

Alex

Alexander L. Friend, Ph.D.

Station Director, Pacific Southwest Research Station

Science that makes a difference.

Sherri Eng

DEPAR TMENT OF AGRICULT URE

1
Adapting to a Changing 

Climate, Urban Natural 

Resources Stewardship, 

Water, and Wildland Fire

Four strategic plans outline the Pacific 

Southwest Research Station's (PSW) 

direction over the next decade for 

adapting to a changing climate, urban 

natural resources stewardship, water, 

and wildland fire. In each of these areas, 

PSW's research, development, and 

technology will be interdisciplinary and 

collaborative. The strategies reach 

across PSW's research programs and 

are coordinated with the Forest Service 

Pacific Southwest Region, National 

Forests, other Research Stations, 

universities, and other government 

organizations. The plans focus on 

natural resources in California, Hawai‘i, 

and the U.S.-affiliated Pacific Islands.

ADAPTING TO A CHANGING CLIMATE

For nearly a century, Forest 

Service Research and 

Development has investigated 

important stressors on the 

Nation's forests and 

rangelands and developed 

practices to manage for 

healthy, sustainable, productive, 

and resilient ecosystems. Over 

the last two decades, our research has specifically 

improved the understanding of how a changing 

climate impacts our Nation's forests, rangelands, and 

urban areas. We have also examined how forests and 

forest management can reduce emissions or increase 

carbon sequestration to help mitigate a changing climate 

by reducing greenhouse gases in the atmosphere.

WATER

Approximately 87 percent of 

our country's fresh water 

supply originates from forests 

and agricultural lands. More 

than 200 million people rely 

on their drinking water from 

public and private forests and 

grasslands. PSW's research 

helps inform future 

management decisions to protect water-related 

goods and services, such as abundant and clean 

drinking water, fish and wildlife habitat, slowing of 

storm runoff, and water-related recreational 

opportunities. Our water strategy plan concentrates 

on four critical components: projecting the impacts 

of disturbance on water and the resulting goods and 

services; understanding the watershed processes 

that will be impacted by these disturbances; 

identifying critical aquatic species at risk and 

developing appropriate tools and management 

practices to mitigate adverse impacts; and 

developing best management practices and tools to 

maintain watershed health in natural ecosystems and 

for urban areas to help mitigate the impact of a 

changing water supply. 

URBAN NATURAL RESOURCES STEWARDSHIP

More than 80 percent of the 

U.S. population lives in urban 

areas, cities and suburbs. 

Forest Service Research and 

Development strives to foster 

the proper care of natural 

resources and the 

advancement of ecosystem 

services in urban landscapes. 

PSW and its partners continue to develop tools that 

will assist the citizenry in making appropriate 

planning and management decisions on creating 

healthy and sustainable urban ecosystems for their 

communities. Focus areas include: urban water, 

green infrastructure, humans and fire, and 

environmental justice.

WILDLAND FIRE

The mission of PSW's wildland 

fire research is to provide the 

knowledge and tools that 

managers need to reduce 

negative impacts and 

enhance beneficial effects of 

fire and fire management on 

society and the environment. 

Our science will guide land 

management practices so they reflect an 

understanding of the diverse impacts of fire and fuels 

management, and of fire's role as a disturbance on a 

regional, as well as global scale; assist individuals and 

communities to recognize their options and accept 

their responsibilities regarding fire safety when living 

in fire-affected ecosystems; and provide fire 

managers with state-of-the-art, science-based 

knowledge and decision-support tools.

Steve McKelvey

California State University, Fresno Pat Winter

U.S. Forest Service

2
USDA Forest Service

Pacific Southwest Research Station Overview

Research is organized into four science programs:

1) Conservation of Biodiversity

Station scientists conduct research on genes, species, habitats, 

landscapes, and the biological processes necessary to maintain 

diversity of organisms and functioning ecosystems. Research 

focuses on enhancing the conservation, ecology, and evolution 

of species and habitats, and the restoration and maintenance of 

degraded ecosystems.

 2) Ecosystem Function and Health

Station scientists examine forest function and conduct research 

to protect and preserve water, air, and soil resources while 

considering the effects of a changing climate, unpredictable 

precipitation, air pollution, and growing threats from pests and 

pathogens.

3) Fire and Fuels

Station scientists conduct research on how fire behavior affects 

fuel types and conditions and how physical properties of fuels 

influence fire severity and intensity. Research includes decisionsupport models that analyze risk, resource allocation economics, 

and fire danger forecasting. 

4) Urban Ecosystems and Social Dynamics

Station scientists examine the interconnections of people and 

natural resources. Research focuses on developing knowledge 

and tools in natural resource management to better serve the 

public, and to connect urban dwellers with public lands through 

urban forestry and social science research.

•	 Headquarters in Albany, Calif.

•	 Eight laboratories in California and Hawai‘i

•	 12 active Experimental Forests and Ranges; one Experimental Watershed

•	 Research is also conducted in more than 90 research natural areas (RNAs)

•	 Pacific Southwest Research Station is one of five research stations in the U.S. Forest Service

•	 249 employees (160 permanent, fluctuating up to 89 temporary)

•	 Conterminous with Region Five of the National Forest System

CALIFORNIA

HAWAI‘I

Station Headquarters

Lab Location

Experimental Forests and Ranges

Experimental Watershed

North Mountain

San Dimas

San Joaquin

Teakettle

StanislausTuolumne

Challenge Sagehen

Caspar 

Creek

Swain 

Mountain

Blacks

Mountain

Redwood 

Onion Creek 

Davis

Albany

Fresno

Riverside

Redding

Placerville

Arcata

Kings River

Hilo

HETF

Pacific Southwest Research Station

DEPAR TMENT OF AGRICULT URE

3
0

50

100

150

200

250

300

2011 2012

NUMBER OF PUBLICATIONS

Peer-reviewed

FS Series

Other

Journal

Total

PUBLICATIONS

0

5

10

15

20

25

30

IN US $ MILLIONS

INCOMING FUNDING

BASE RESEARCH APPROPRIATIONS

TOTAL FUNDING

EXTRAMURAL FUNDING RECEIVED

FY 2008 FY 2009 FY 2010 FY 2011 FY 2012

FY 2011 FY 2012

PEER-REVIEWED

TOTAL PUBLICATIONS

JOURNAL

OTHER

Pacific Southwest Research Station at a Glance

FY 2O12 STATISTICS 

Incoming Funding

Base research appropriations: $22.5 million

Extramural funding received: $3.7 million

Total funding: $26.2 million

Distribution of Funds

Fixed costs (salaries, operations, overhead): $20.3 million

Appropriated funds distributed to cooperators: $5.3 million

Workforce 

Total station workforce: 249

Permanent: 160

Temporary: 89

Science staff: 197 

Scientists: 56

Science support: 141

Leadership and Administrative support staff: 52 

Publications

Total publications: 267 

Of the total publications, 149 (56%) were peer-reviewed

Journal: 130

Other publications: 131 

Forest Service series: 6

Web Metrics

Number of visits to the PSW web site: 99,720 

Number of visitors to the PSW web site: 65,382

Source countries or territories visits originated from: 188 

Page views of PSW publications through Treesearch: 17,225

Followers on Twitter(@usfs_psw): 300

4
Funding Partners for 2012

Cooperators Who Received Funding for Studies From PSW

Association of Fire Ecology

BMP Ecosciences

Cal Poly Corporation

California Conservation Corps

California Forestry Association

California State University

Carnegie Institution of Washington

Claremont Graduate University

Colorado State University

Conservation Biology Institute

Coral Reef Research Foundation

Cornell University

EcoLayers, Inc.

EM Hydrology, LLC

Environmental Incentives

Forest Research Agency, United Kingdom

Hawaii Wildfire Management Organization

Hui Kako’o O Laupahoehoe

Humboldt State University

Integral Ecology Research Center

Klamath Bird Observatory

Macgregor Bates

Michigan State University

North Carolina State University

Northern Arizona University

Oregon State University

Pennsylvania State University

Phytosphere Research

PRBO Conservation Science

Riverside-Corona Resource 

Conservation District

Spatial Informatics Group

Texas A&M (Texas AgriLife Research)

Texas Southern University

The Nature Conservancy

University of Alabama, Huntsville

University of British Columbia

University of California Cooperative 

Extension, Berkeley

University of California Cooperative 

Extension, Marin County

University of California, Berkeley

University of California, Davis

University of California, Los Angeles

University of California, Merced

University of California, Riverside

University of California, San Diego

University of California, Santa Barbara

University of Florida

University of Hawaii

University of Montana

University of Nevada, Reno

University of Wisconsin

Urban Tilth

US Department of Agriculture - 

Agricultural Research Service (ARS)

US Department of Commerce - 

National Oceanic and Atmospheric 

Administration

US Department of the Interior - Fish 

and Wildlife Service

US Department of the Interior - 

National Park Service

US Department of the Interior - US 

Geological Survey

Washington State University 

Clients Who Provided Funding for Studies to PSW

Bat Conservation International

California Department of Fish and Wildlife

California Department of Forestry and 

Fire Protection (CalFIRE)

California Energy Commission

City and County of Denver

Forest Research and Management 

Institute, Romania

Iberdrola Renewables

ISCA Technologies Inc.

Lang, Railsback & Associates

New York Botanical Garden

Redwood Community Action Agency

San Francisco Public Utilities Commission

Save the Redwoods League

University of California, Berkeley

University of Nevada, Reno

US Department of Agriculture - 

Agricultural Research Service

US Department of Agriculture - Animal 

and Plant Health Inspection Service

US Department of Agriculture - National 

Institute of Food and Agriculture

US Department of Defense - Army Corp 

of Engineers

US Department of Defense Strategic 

Environmental Research and 

Development Program (SERDP)

US Department of Energy

US Department of the Interior - Bureau of 

Land Management

US Department of the Interior - Fish and 

Wildlife Service

US Department of the Interior - National 

Park Service

US Department of the Interior - US 

Geological Service

Wood Buffalo Environmental Association

FUNDING USED 

INTERNALLY: $20.9 million

FUNDING

AWARDED:

$5.3 million

Of the $26.2 million available to PSW, 20.2% 

was awarded as grants to our cooperators.

5
PROGRESS RANCH COMMUNITY GARDEN PROJECT, PSW-DAVIS

Forest Service employees from the 

Pacific Southwest Research Station 

and State and Private Forestry in 

Davis, Calif. kicked off Earth Day on 

April 22, 2012, by completing a 

three-month community garden 

project for a local boys' home. 

Forty volunteers worked with six 

boys from Progress Ranch, a 

residential home in Davis for boys 

ages 6-12, to build raised bed 

gardens in the facility's backyard. 

Each boy tended to and planted 

vegetables in his own plot. 

The project met the objectives of the 

USDA's “People's Garden” Initiative 

objectives for community service, 

partnerships, and sustainability. 

Employees contributed more than 

$500 for construction materials 

and the local Ace Hardware store 

and its employees donated another 

$175 for seeds, seedlings, trellises, 

and other materials. 

U. S. Forest Service U. S. Forest Service

Community Service

STARTS WITH A SEED, PSW-HILO

In April 2011, the station's Institute 

of Pacific Islands Forestry in Hilo, 

Hawai‘i launched the Starts with a 

Seed program with the mission to 

connect children to Hawai‘i's 

forests. Funding from the More 

Kids in the Woods program in 

FY2012 helped expand and ensure 

the program's success. The 

program hosted 441 K-12 students, 

35 community members, and 11 

university students on field trips 

and service learning trips. Many of 

the participants came from urban 

and/or underserved communities. 

Field trips are designed to pique 

participants' curiosity as they 

experience the outdoors, develop 

an appreciation for forests, learn 

about ongoing research projects, 

and hear about native tree uses and 

stories. Service learning trip 

participants gather native seeds for 

propagation, prepare planting sites, 

and plant native plants in degraded 

forest areas with partners. Program 

coordinators also conducted two 

“train the trainer” workshops on 

ecological restoration techniques, 

where 11 educators and students 

gathered seeds and conducted 

plant monitoring. 

The program worked with two East 

Hawai‘i charter schools to purchase, 

build, and supply a greenhouse for 

each campus. Additionally, the 

program connected Hawai‘i Island 

students to students in the Jasper 

National Park stewardship 

education project located in the 

Canadian Rockies in Alberta. 

Students shared experiences and 

points of view on temperate/

tropical forests via video 

teleconference.

Program partners include Mauna 

Kea Watershed Alliance, University 

of Hawaii at Hilo, Pacific Internship 

Programs for Exploring Science, 

Department of Hawaiian 

Homelands, Hawai‘i National Park 

Service, Kohala Watershed 

Partnership, Three Mountain 

Alliance, Kohala Center, and the 

Hawaii Division of Forestry and 

Wildlife (Natural Area Reserves).

Kainana Francisco

6
RICHMOND EDIBLE FOREST, PSW-ALBANY

On Jan. 16, 2012—Martin Luther 

King Jr. National Day of Service—

staff from the station's Albany 

headquarters partnered with the 

Urban Tilth in Richmond, Calif. to 

plant some 60 fruit trees on the 

Richmond Edible Forest. They 

joined nearly 400 community 

volunteers who worked on 

multiple sites along the Richmond 

Greenway—a former three-mile 

rail byway bordered by 32 acres of 

community gardens, composting 

sites, and recreational space in a 

densely populated, underserved 

community—removing weeds, 

collecting seeds, and replanting 

garden beds. For the past several 

years, station staff has collaborated 

on the edible forest with Urban 

Tilth, a nonprofit that promotes 

community agriculture in west 

Contra Costa County, by providing 

scientific expertise, as well as 

physical labor, to the project. The 

edible forest serves as an 

environmental education site where 

station scientists and Forest Service 

land managers teach kids about the 

benefits of trees and forested 

landscapes. 

The project is a partnership 

between the U.S. Forest Service, 

Urban Tilth, the city of Richmond, 

and the West Contra Costa Unified 

School District. The partnership 

engages 700 underserved youth in 

“I believe in making sure that 

everyone has an opportunity to 

succeed,” said Armando GonzálezCabán, a research economist at 

PSW-Riverside, who has been 

volunteering for Centro de Niños 

for more than 25 years. “These 

children are from families in need, 

so why not do something for them 

to make their lives better?”

CENTRO DE NIÑOS, PSW-RIVERSIDE

Scientists and staff at the station's 

Riverside lab continued its longtime community relationship with 

Centro de Niños, a children's center 

run by Concilio for the Spanish 

Speaking of the Inland Empire. The 

Riverside, Calif.-based nonprofit is 

dedicated to providing childcare 

services and bilingual instruction to 

children of underserved and 

financially needy families in the 

area. 

During the 2011 holiday season, 

station scientists and staff kicked 

off a Thanksgiving food drive and a 

holiday toy drive for Centro de 

Niños children and families. Eleven 

families received a box with all the 

fixings for a Thanksgiving dinner, 

including a turkey, potatoes, rice, 

beans, yams, flour, canned 

vegetables, juices and dessert. To 

get into the holiday spirit, about 90 

children, ages 3-5, took home a 

special holiday gift. 

In September 2012, just prior to the 

beginning of the new school year, 

scientists and staff donated 

backpacks, lunch boxes, pencils, 

paper, crayons and other school 

supplies to 12 entering 

kindergarteners from Centro de 

Niños. They also donated 325 

pounds of dried goods to Centro de 

Niños through the Feds Feed 

Families campaign. 

education programs to learn how to 

install “edible forests” in Richmond 

parks and school areas. 

PSW helped fund The Richmond 

Edible Forest Project through a U.S. 

Forest Service More Kids in the 

Woods program grant. The More 

Kids in the Woods program's goal is 

to work with community partners 

to help America's youth learn more 

about their local environment and 

careers in natural resources.

U..S. Forest Service

DEPAR TMENT OF AGRICULT URE

7
Stanislaus-Tuolumne Experimental Forest (STEF)

Prior to historical logging and fire suppression, 

forests of the Sierra Nevada were extremely 

heterogeneous, which helped make them resilient to 

fire and other threats. Today, forest management 

practices focus on improving the resilience of forest 

stands to large-scale crown fires. Mechanically 

thinning small trees while retaining larger ones is one 

way to improve resilience. But this type of thinning 

can lead to a relatively even forest structure—

consisting of trees of the same age—which 

decreases the habitat diversity for wildlife and other 

forest species. PSW scientists recently performed 

variable-density thinning on the STEF in an effort to 

produce a more grouped arrangement of trees, 

which would create heterogeneity at a scale 

beneficial for wildlife and understory plant species, 

while simultaneously increasing resilience to wildfire.

Kings River Experimental Watershed (KREW)

National Forests in the Sierra Nevada provide 45 

percent of the surface water to California. All life 

needs water, and these waters support human 

activities, such as agriculture and recreation, as well 

as quality stream conditions for fish and wildlife. The 

Kings River Experimental Watersheds (KREW) project 

has watersheds at the rain-snow-interface zone and 

at the snow-dominated zone. The lower elevation 

site is representative of what the high elevation site is 

expected to become as climate changes. This 

research project compares the condition and 

processes of watersheds with forest management 

practices to ones that are undisturbed. No pairedwatershed research on forest management existed in 

the Sierra Nevada before PSW established the KREW 

project in 2000. 

Although all watersheds receive about the same 

amount of precipitation, those that are snowdominated produce more streamflow over a longer 

time period. Sixty percent of the water in the streams 

comes from subsurface flow while over-landsnowmelt runoff contributes less than 40 percent. 

Trees at the rain-snow-interface zone are active all 

winter and use significantly more soil water than 

previously believed, thus allowing less subsurface 

water to enter streams. These results indicate that 

even if the same amount of precipitation occurs as 

climate changes in the southern Sierra Nevada, less 

of it will come as snow. Higher elevation trees will 

likely use more water resulting in less water flowing 

from headwater streams to valley rivers, and an 

earlier and shorter peak in streamflow. The current 

information on streamflow variability and water 

balance will be compared to data collected after tree 

thinning in 2012 to see if any detectable increase in 

water availability occurs from vegetation removal for 

forest restoration.

Recent activities and achievements on PSW's Experimental Areas:

Michael Sullivan

Amber Olsson

8
Research focuses on the following areas:

•	 Determine how biophysical factors influence the function and

productivity of tropical, subtropical and temperate ecosystems;

•	 Quantify and predict ecosystem responses and adaptation to

environmental stressors;

•	 Define and measure the impacts of biotic and abiotic stresses on

hydrological and atmospheric systems; and

•	 Develop models andtools, andevaluate management options forrestoring,

sustaining and enhancing ecosystem function and productivity. 

Our forests and wildland ecosystems are exceedingly 

diverse and provide a wide array of societal goods and 

services. From clean water, timber and non-timber 

products, and carbon sequestration to recreational use, 

aesthetic beauty, and native biodiversity, these ecosystems 

are national treasures that contribute to the prosperity of 

current and future generations. A growing list of 

environmental pressures, including climate and land-use 

change, water scarcity, and an increasing human population, 

threaten the health and integrity of these ecosystems. 

The Ecosystem Function and Health Program focuses 

on the interactions among changes in or brought about by 

biotic and abiotic factors, such as temperature and 

precipitation, invasive species, air pollution, insects, 

pathogens, and past and current land management 

actions. Station scientists conduct research that provides an 

integrated understanding of the biophysical conditions that 

threaten ecosystem resilience, including how 

environmental changes are initiated and progress, what 

thresholds are associated with these changes, and what the 

consequences are of crossing identified thresholds. 

Ecosystem Function and Health

Sean Eagen

Andrzej Bytnerowicz Sherri Eng

9
Streamflow and water balance 

data to gauge the effects of a 

changing climate on California's 

water resources

Research at the Kings River 

Experimental Watershed in the 

southern Sierra Nevada has 

established the current and 

natural range of variability for 

headwaters watersheds for the 

first time. Reliable data 

collection and analysis is critical 

to answering vexing questions 

about how various silvicultural 

treatments impact water 

quality, quantity, and 

biodiversity. This is the only site that that can provide this information in the southern Sierra 

Nevada. Years of data will be compared to erosion and sediment measurements taken after forest 

thinning and prescribed fire to quantify effects of forest restoration activities. This effort provides 

unparalleled data on infrastructure, characterization, and research history for climate research 

and supports partnerships within our national networks that include the National Science 

Foundation’s National Ecological Observatory Network (NEON), the Southern Sierra Critical Zone 

Observatory (CZO), and the University of California.

Managing Sierra Nevada forests

There has been widespread interest in applying new forest practices based on concepts presented 

in the 2009 U.S. Forest Service General Technical Report PSW-GTR-220, "An Ecosystem Management 

Strategy for Sierran Mixed-Conifer Forests." A new 2012 report (PSW-GTR-237) summarizes the 

state of the science in topics relevant to this forest management approach, presents case studies of 

collaborative planning efforts and field implementation of these new practices, and clarifies some 

of the concepts presented in GTR-220. It also describes a method for assessing forest heterogeneity 

at the stand level using the Forest Vegetation Simulator and a new geographic information system 

tool for project level planning that classifies a landscape into different topographic categories. 

While this collection of papers presents information and applications relevant to implementation, it 

does not offer standards and prescriptions. Forest management should be flexible to adapt to local 

forest conditions and stakeholder interests. This report does, however, strive to clarify concepts 

and present examples that may improve communication with stakeholders and help build 

common ground for collaborative forest management. 

2012 Research Highlights

Prescribed burning and mechanical thinning pose little risk to forest ecology

Current conditions of many seasonally dry forests in the western and 

southern U.S., especially those that once experienced low- to moderateintensity fire regimes, leave them uncharacteristically susceptible to 

high-severity wildfire. Using prescribed fire and mechanical thinning are 

generally successful in making stands more resilient to high-intensity 

wildfire. Station scientists and collaborators found that these fuel 

reduction methods can be conducted with few negative consequences 

to the ecosystem. While mechanical treatments do not serve as 

surrogates for fire, their application may help mitigate costs and liability 

in some areas. Treatment effects on fire hazard are transient, indicating 

that repeated applications are necessary to maintain desired effects.

Study shows sources of air pollution in the Lake Tahoe basin 

Station scientists conducted a study in the Lake Tahoe Basin to address 

the distribution of ozone, its precursors, and nitrogen oxides. Scientists 

used passive samplers to monitor air quality at 34 sites located at various 

elevations in and around the basin. Scientists found that air pollution 

from the California Central Valley caused high concentrations of ozone on 

the western slope of the Sierra Nevada, but these emissions did not affect 

air quality in the Lake Tahoe Basin. Local emission sources are most likely 

the cause of elevated ozone levels at high elevation sites on the eastern 

side of the basin. These findings will help to develop management 

strategies aimed at improving air quality of the Lake Tahoe Basin.

Air pollution thresholds used to protect U.S. ecosystems

Advances in defining thresholds for acceptable air pollution exposure 

have greatly increased the capacity to protect and restore at-risk 

ecosystems. The use of these thresholds applies to impacts on aquatic 

and terrestrial ecosystems that are affected by pollutants, such as 

mercury, sulfur and excess nitrogen. This research will benefit air quality 

specialists, land managers, scientists, policymakers and the U.S. Congress. 

The critical loads developed in this work are being applied for natural 

resource protection by the Forest Service, National Park Service, and 

others. A federally-mandated peer reviewed report was also submitted 

to Congress providing an update on the status of pollutant emissions, 

atmospheric deposition, ecosystem effects, and projections of emissions 

necessary to prevent future adverse ecosystem effects in the U.S.

Andrzej Bytnerowicz

10
Fire and Fuels

Research focuses on the 

following areas:

•	 Improve measurement, modeling,

and prediction of wildland fire

and weather phenomena in

complex landscapes and fuels;

•	 Determine the ecological effects of

fire and fire removal on landscapes

throughout California, Hawai‘i, and

the U.S.-affiliated Pacific Islands;

•	 Evaluate the short- and long-term

outcomes of fuels, fire, and postfire management strategies;

•	 Determine and quantify the

interactions between climate,

vegetation, and fire in the face of a

changing climate and improve our

understanding and predictability

of these interactions in order to

manage forests and wildlands

more effectively; and

•	 Describe and quantify uncertainty

and risk in a science-based

decision-making framework for

fire and land management

planning.

Steve McKelvey

Managing fire and the vegetation conditions that fuel fire is a paramount challenge to land 

managers throughout most of California, Hawai‘i and the U.S.-affiliated Pacific Islands. The 

mission of the Fire and Fuels Program is to provide scientific findings that will improve 

management actions intended to enhance resiliency and sustainability of wildland ecosystems 

affected by fire, and reduce the potential for adverse effects resulting from wildland fire, 

including loss of life and property.

11
2012 Research Highlights

Science helps guide forest planning

Station scientists led an innovative year-long effort to synthesize and 

distill recent scientific research which will guide the revision of land and 

resource management plans for national forests in the Sierra Nevada. 

Highlights of this approach included analysis and design of treatments 

that reduce the extent of severe wildfire while avoiding impacts to 

sensitive species; consider opportunities to promote resilience of local 

communities; and apply principles of adaptive management to evaluate 

outcomes. The science team produced an integrated report on strategies 

to promote long-term socioecological resilience in the Sierra Nevada 

bioregion in the face of climate change, increases in wildfire severity and 

extent, demographic changes, and other expected stressors.

Managing wildfire may increase forest restoration

Forests in the Sierra Nevada are vulnerable to large and severe wildfires 

that have the potential to impact human communities, habitat for 

sensitive wildlife species and water resources. Increasing the amount of 

fire on a landscape to reduce the potential damage of future wildfires 

may seem counterintuitive. However, station scientists have found that 

using managed wildfire under less-than-extreme fire weather 

conditions across large portions of Sierra Nevada forests may alleviate 

the current hazardous fuels/fire deficit problem. 

Fire size and severity trends in Northern California show that managed 

wildfire may reduce severe fire outbreaks

Research indicates that fire size and severity have been increasing over 

the last several decades. This assessment of large wildfires in Northern 

California indicates that using managed wildfire under less-thanextreme fire weather conditions forests may help alleviate the current 

hazardous fuels/fire deficit problem. Analysis of wildfire trends from 

1910–2008 revealed ways to increase forest resilience and limit severe 

fire effects, reducing vulnerability to large and severe wildfires by 

managing wildfires for resource benefits. Findings suggest that under 

conditions typical of widespread lightning-fire outbreaks, wildfires 

could be more extensively used to achieve ecological and 

management objectives in Northern California.

FireMapper technology tracks effectiveness of fire retardant

Aerial assault on wildland fires with air tankers and fire retardant is a critical and expensive 

element of modern fire suppression. Yet the practical effects of retardant application on fire 

behavior have not been critically assessed across the range of conditions encountered in active, 

large wildfires. PSW is using its specialized FireMapper remote-sensing system in a nationwide 

study quantifying and assessing the response of fires to retardant applied under operational 

conditions. 

Station partners with NOAA to predict fire risk

An in-depth knowledge of the spatial and temporal variability of fire weather variables is needed 

to predict fire danger. In response to this need, the Forest Service and the National Oceanic and 

Atmospheric Administration (NOAA) began engaging in collaborative research in weather and 

climate-related physical fire science. Station scientists will develop a management system that 

can predict the timing, location, and severity of wildfires. This collaborative research will enhance 

the understanding of fire risk using climate forecasts, and will provide a tool to improve the 

development of forest and wildland management strategies. 

U.S. Forest Service

U.S. Forest Service 

12
U. S. Forest Service

Urban Ecosystems and Social Dynamics

Research focuses on the following areas:

•	 Determine the relationships among human uses, human values,

ecosystem services, and management;

•	 Ascertain the roles of changing demographics, urbanization,

socioeconomics, and technology on use and sustainability of natural

resources; and

•	 Examine the impacts of public policies on ecological and social

patterns and processes along rural-to-urban gradients.

The interconnection between humans and nature is complex and enduring. 

People need and yearn for the resources that only nature can provide: clean 

water, clean air, natural scenic beauty, and a connection to the land and 

wildlife. The Pacific Southwest Research Station strives to maintain forests, 

sustain functioning ecosystems in urban and wildland areas, enhance and 

protect quality of life, and ensure benefits to society through interdisciplinary 

research that examines urban ecosystems and social dynamics of natural 

resources conservation, management, and restoration.

The Urban Ecosystems and Social Dynamics Program conducts research 

and communicates science needed to understand and enhance the 

interconnections among ecosystems, people, and societies. 

13
2012 Research Highlights

Assessing the impact of a changing climate on forest diseases

A changing climate is projected to have far-reaching environmental 

impacts both domestically and abroad. A PSW report examined the 

impact of climate change on forest diseases and how these pathogens 

will ultimately affect forest ecosystems in the Western United States and 

Canada. Drawing on a large body of published research, the report 

details the effects of eight forest diseases under two climate-change 

scenarios—warmer and drier conditions, and warmer and wetter 

conditions. Forest diseases discussed in the report include foliar diseases, 

Phytophthora diseases (such as sudden oak death), stem rusts, canker 

diseases, dwarf mistletoes, root diseases, and yellow-cedar decline. 

Relationship to forests linked to recreationists' self-identity 

Recreational uses of forest lands are psychologically and socially 

important. Data collected from recreationists in both the United States 

and Greece show that a person's attraction and connection to the 

forest has a positive effect on his or her sense of identity and social 

bonding with others. This suggests that forest recreation experiences 

are both immediately fulfilling and important to one's quality of life 

and sense of self. This research contributes to an understanding of the 

role of outdoor recreation and will help inform managers and 

policymakers who set priorities on socially-relevant ecosystem 

functions and services. 

Urban tree growth modeling: why tree size matters

It is well-known that large trees provide more ecosystem services than small trees. Station 

scientists have developed growth equations for urban tree species throughout the U.S. and are 

catalyzing new collaborations between researchers and professionals in the planning and 

management of high performing landscapes. This research helps managers select, locate, and 

manage trees to more effectively cool urban heat islands, conserve energy, filter air pollutants, 

reduce runoff, sequester carbon, and promote human well-being. This science has resulted in a 

greater awareness of tree benefits, increased investment in tree management, and more 

productive urban forests.

Guidelines help fire managers in Europe combat large fires

Historically, forest fires have played a significant role in shaping European, and most particularly, 

Mediterranean forest ecosystems. During the last few decades, socio-demographic changes in 

the Mediterranean basin countries have significantly altered land use patterns. These have 

resulted in abandonment of large areas, reduction in agricultural crops, and reconversion to forest 

lands. A concomitant resulting change has been an increase in the number, intensity, and size of 

large fires in Europe. In response to these events, the European Union Commission chartered a 

fire science research project to address the causes and consequences of large fires in Europe and 

offer potential solutions. PSW was a member of the international Scientific Steering Committee, 

providing guidance and technical review for the Fire Paradox Project. From this project, fire 

scientists developed guidelines for policymakers and fire managers on how to better respond to 

fire management problems in their regions. 

George Gonzalez, City of Los Angeles

Elke Schuster

14
Mark Linnell Laura Warman 

Our geographic area includes oceanic islands, elevational clines from coastal to 

alpine ecosystems in temperate and tropical ecosystems, and species and 

communities that occur nowhere else in the world. The area faces significant 

species extirpations and extinctions, with remaining natural areas continuing 

to be threatened. 

The Conservation of Biodiversity Program provides high-quality, relevant 

information across the conservation continuum: status, threats, vulnerable 

components, response of organisms and ecosystems to threats, tradeoffs in 

desired management outcomes, efficacy of management approaches through 

adaptive management, restoration and recovery techniques and tools, and 

effectiveness monitoring and evaluation techniques. 

Research focuses on the following areas:

•	 Determine environmental conditions needed for terrestrial species

persistence;

•	 Identify conditions that can support aquatic biodiversity and

ecosystem services;

•	 Determine the genetic origins of traits that can enhance tree

adaptability and utility; and

•	 Develop innovative approaches to reduce ecological impacts of

non-native species.

Conservation of Biodiversity

15
Brown Creepers respond negatively to forest edges

Station researchers studied the response of Brown Creepers (Certhia americana) to forest edges in 

the Sierra Nevada. They found that Creepers were more abundant in plots with less high-contrast 

edge, nested farther from soft and moderate edges, and reproduced more successfully farther 

from moderate or hard edges. Results suggest that Creepers responded, in part, to edges with 

greater contrast between adjacent patches that primarily resulted from natural discontinuities. 

These findings were surprising as previous work suggested that edge effects and the processes 

underlying them may differ in western coniferous forests due to their intrinsic natural 

heterogeneity. These results highlight the importance of retaining fairly large patches of 

continuous mature and late-seral forest.

Using a “fantasy football” model to build hybrid ecosystems in Hawaiian lowland wet forests

As novel assemblages of native and non-native species become increasingly common globally, 

many conservation and restoration efforts have concentrated on the removal of exotic—and 

often invasive—species. In some cases, removing non-native species is no longer economically or 

ecologically feasible. Station scientists developed an approach similar to fantasy football, where 

"teams" of species are picked to work together to form self-sustaining units in Hawai ́i. Scientists 

presented an approach for species choice ("players") based on characteristics of native and 

non-invasive species, and on diversity indices from existing forests. New hybrid communities can 

be experimentally assembled based on principles of complementarity and redundancy.

 North Central Research Station Archive, U.S. Forest Service, Bugwood.org

2012 Research Highlights

Model gauges effects of passage barriers on trout populations

Loss of habitat connectivity in stream networks can create problems 

for the persistence of valuable populations of aquatic animals. 

Resource managers need tools to identify and prioritize actions. Station 

researchers and cooperators used a spatially-explicit model of a 

northwestern California watershed to establish a framework to better 

understand the effects of barriers on fish populations and identify 

those of greatest significance to population size and persistence. The 

approach has been used to address a variety of key management 

issues, including cumulative effects analysis, the effects of streamflow 

diversions on fish populations, prediction of habitat restoration 

outcomes, and the effects of water quality on fish populations. 

Forest Inventory Analysis (FIA) data helps estimate habitat value

Wildlife species use habitat at various scales. Resting locations are often 

the most difficult to assess and monitor over large areas. Because these 

habitats are critical to the conservation of the fisher (Martes pennanti), a 

rare forest carnivore, forest managers require quantitative tools to monitor 

resting conditions over time. Station scientists developed a predictive 

model using Forest Inventory Analysis plot data to characterize the value 

of resting habitat across northwestern California and quantitatively 

evaluate the effect of forest management on these habitats.

Landbird monitoring network gathers, archives and shares bird 

population data

Landbirds play a vital role in the environment. With an increasing focus 

on global-scale environmental issues, there is an urgent need to 

address large-scale issues for landbird populations. A wealth of data 

from projects is lost yearly that can inform these analyses, especially 

long-term trends in bird populations. Station researchers partnered 

with other governmental agencies, organizations and individuals to 

create the Landbird Monitoring Network of the Americas (LaMNA) to 

help fill this gap by actively searching, archiving, and making datasets 

available for future generations. LaMNA currently has archived almost 4 

million records of capture and census data from 60 cooperators in 

North and South America, and works to increase communication 

between researchers through its web site (www.klamathbird.org/lamna) 

and regular newsletters, as well as facilitating large-scale studies 

between multiple researchers.

16
PSW-Albany (Headquarters)

800 Buchanan Street

West Annex Building

Albany, CA 94710-0011 

Phone: (510) 559-6300

Fax: (510) 559-6440 

PSW-Arcata

1700 Bayview Drive

Arcata, CA 95521-6013 

Phone: (707) 825-2900

Fax: (707) 825-2901 

PSW-Davis

1731 Research Park Dr.

Davis, CA 95618 

Phone: (530) 759-1700 

Fax: (530) 747-0241 

PSW-Fresno

2081 E. Sierra Avenue

Fresno, CA 93710-4639 

Phone: (559) 323-3200

Fax: (559) 297-3355 

PSW-Hilo, Institute of 

Pacific Islands Forestry

60 Nowelo Street 

Hilo, HI 96720 

Phone: (808) 933-8121

Fax: (808) 933-8120

PSW-Placerville, Institute of 

Forest Genetics

2480 Carson Road

Placerville, CA 95667 

Phone: (530) 622-1225

Fax: (530) 622-2633 

PSW-Redding

3644 Avtech Parkway

Redding, CA 96002 

Phone: (530) 226-2530

Fax: (530) 226-5091 

PSW-Riverside

4955 Canyon Crest Drive

Riverside, CA 92507 

Phone: (951) 680-1500

Fax: (951) 680-1501 

Locations

The Forest Service of the U.S. Department of Agriculture is dedicated to the principle of multiple use management of the Nation's forest resources for sustained yields of wood, water, 

forage, wildlife, and recreation. Through forestry research, cooperation with the States and private forest owners, and management of the national forests and national grasslands, it 

strives—as directed by Congress—to provide increasingly greater service to a growing Nation. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs 

and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic 

information, political beliefs, reprisal, or because all or part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) 

Persons with disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA's TARGET Center at (202) 

720-2600 (voice and TDD). To file a complaint of discrimination, write USDA, Director, Office of Civil Rights, 1400 Independence Avenue, SW, Washington, DC 20250-9410 or call (800) 

795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer.

PSW Research Station Organization

Station Director

Dr. Alexander L. Friend 

(510) 559-6310

afriend@fs.fed.us

Program Managers

April 2013 Electronic version available at www.fs.fed.us/psw/about/accomplishments/

Credits 

Director of Communications—Michael Sullivan

Writers—Sherri Eng, Caitlin Heavey, and Michael Sullivan

Graphic design—Beth Purcille

Web design—Keiko Williams

Assistant Director, Research

Dr. Jane L. Hayes

(510) 559-6313

jlhayes@fs.fed.us

Assistant Director, Business 

Operations

Alfred Kwok

(510) 559-6310

alkwok@fs.fed.us

Director of Communications

Michael E. Sullivan

(510) 559-6434

mesullivan@fs.fed.us

Director of Research Planning

Caitlin Heavey 

(510) 559-6312

clheavey@fs.fed.us

Ecosystem Function and Health

Vacant

Fire and Fuels 

Dr. Rick Bottoms

(530) 759-1703

rmbottoms@fs.fed.us

Urban Ecosystems and Social Dynamics

Dr. Deborah Chavez

(951) 680-1558

dchavez@fs.fed.us

Conservation of Biodiversity 

Dr. Patricia Manley

(808) 854-2601

pmanley@fs.fed.us

DEPAR TMENT OF AGRICULT URE