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Research Highlights - Urban Natural Resource Stewardship

Check out our 2014 Research Highlights, focusing on Science for a Healthy Environment and Better Quality of Life.
Research Highlights
More than 80% of the U.S. population lives in urban and suburban areas. The urban forests---street and park trees as well as landscape plantings on private lands---provide important ecosystem services to urban residents and workers. A healthy urban forest can help reduce air pollution and urban core temperatures and thus make cities more livable. Mitigation of past declines of urban forests and open space; maintenance of the health of street trees and open spaces; revitalization of neighborhoods and righting of past environmental injustices are important issues for urban forest managers.
2014 Research Highlights
Air Pollution as a Psychosocial Stressor
Exposure to air pollution and its sources is increasingly viewed as a psychosocial stress, but its nature is not well understood. A Forest Service scientist, with partners from Drexel University, University of Pennsylvania and organizations in South Philadelphia, explored the role of the concept of “place” on risk perception and community stress within data collected from eight focus groups in Philadelphia, Penn. Discussions focused on air pollution, a nearby oil refinery, health, and a proposal for air monitoring. The framework of place-based elements of risk perception includes place identity, stigma, and social control. The findings indicate that air pollution contributes to physical and psychosocial conditions that act as community-level social stressors. Findings also suggest that programs that seek to change behaviors and gather or spread information on issues such as pollution and other environmental concerns will be challenged unless they directly address: (1) the public's identification with a place or industry; (2) immediate environmental stressors such as abandonment, waste, and odors; and (3) public perceptions of lack of social control and fear of displacement.
Partners
Products & Resources:
Trees Improve Human Health and Save Lives
Computer modeling shows that trees’ removal of air pollution reduces human mortality by about 850 people per year nationally

Air pollution is a serious health concern. Trees remove air pollution by intercepting particulate matter on plant surfaces and absorbing gaseous pollutants through the leaf stomata. Forest Service and Davey Institute scientists developed and ran computer simulations with local environmental data showing that trees and forests in the conterminous United States removed 17.4 million metric tons of air pollution in 2010 with human health effects valued at 6.8 billion dollars. This pollution removal equated to an average air-quality improvement of less than 1 percent. Most of the pollution removal occurred in rural areas, while most of the health impacts and values were within urban areas. Health impacts included the avoidance of more than 850 incidences of human mortality and 670,000 incidences of acute respiratory symptoms.
Products & Resources:
Jamaica Bay Social Assessment
A rapid social assessment of urban parkland: Analyzing park use and meaning to inform adaptive management and resiliency planning in New York City’s Jamaica Bay region

New York City’s socially and ecologically diverse Jamaica Bay region, population approximately 900,000, became a focus of resiliency planning and adaptive management efforts following Hurricane Sandy in October 2012. Working in partnership with the Natural Areas Conservancy (NAC) and NYC Department of Parks and Recreation (NYC Parks), Forest Service scientists developed a rapid assessment methodology to understand the public use, social meaning, and stewardship potential of parks in the region. This study assessed the 2,140 acres of public parkland adjacent to the Bay that are managed by NYC Parks. The assessment is spatially explicit, scalable, and replicable so that natural resource managers can use it in adaptive management. The focus on speed and replicability enables managers to examine change in socio-cultural ecosystem services over time in the wake of both acute, large-scale disasters and other chronic forms of disturbance. This study will lead to park profiles, white papers, presentations, and datasets for managers. The pilot has been scaled up to a citywide study exploring the use and meaning of ‘natural areas’ in parks. In the future, social data will be combined with citywide ecological assessment data to inform the conservation and management priorities of the NAC and NYC Parks.
Partners
- Bram Gunther, NYC Department of Parks and Recreation; Sarah Charlop-Powers, Helen Forgione, Clara Pregitzer, Natural Areas Conservancy
Products & Resources:
Cold Winter Temperatures Set Emerald Ash Borer Back in Minnesota

Emerald ash borer has devastated urban and natural forests in most states where it occurs, causing 100 percent mortality of susceptible ash species. Although emerald ash borer has been in Minnesota since 2009, little mortality has been observed and spread has been slower than in other states. Forest Service researchers have been evaluating the role cold temperatures might play in regulating populations of this insect. In general, the insect survives exposure to temperatures from 0 to -20°F by producing cryoprotectants, so in many places, cold temperatures may not have an impact on this insect. However, as within-tree temperatures fall below -20°F, mortality rates begin to increase. With the Polar Vortex in January 2014, air temperature in the Twin Cities fell to -23°F, a temperature that could cause up to 80 percent mortality. Samples taken from cut logs and standing trees that had been outdoors during the winter showed that 60 to 70 percent of larvae had been killed in most locations. Winter mortality of emerald ash borer is unlikely to eliminate this insect but may give natural resource managers more time to respond to this insect in areas where extremely cold winter temperatures (less than -30°F) are common.
Partners
- Minnesota Department of Agriculture; Minnesota Department of Natural Resources; University of Minnesota; Minnesota Environment and Natural Resources Trust Fund
Products & Resources:
2013 Research Highlights
Urban Trees Save Lives
By removing airborne fine particulate matter, urban trees improve human health

Urban air pollution is a serious human health issue. Trees can remove fine particles from the atmosphere and consequently improve air quality and human health. A Forest Service scientist modeled the effects of urban trees on fine particulate matter concentrations and human health for 10 U.S. cities. He found that the total amount of these particles removed annually by trees varied from 4.7 metric tons in Syracuse to 64.5 metric tons in Atlanta, with resulting annual values varying from $1.1 million in Syracuse to $60.1 million in New York City, mostly from the effects of reduced human mortality. Mortality reductions were typically around 1 person per year per city but were as high as 7.6 people per year in New York City. Average annual percent improvement of air quality ranged between 0.05% (San Francisco) and 0.24% (Atlanta). Understanding the impact of urban trees on air quality can lead to improved urban forest management strategies to sustain human health in cities.
Understanding and Supporting the Transition from Job Training to Green Jobs
Grads show positive environmental attitudes and behaviors and increased self-confidence after New York City program

In 2009, the Forest Service’s Northern Research Station and Northeastern Area State and Private Forestry partnered in supporting the MillionTreesNYC Training Program, with $2 million to help fund the employment of graduates from the 9-month training program. The training program, run by the New York City Department of Parks and Recreation and New York Restoration Project, targeted 18- to 24-year-olds who were previously disconnected from the workforce. Graduates of the program worked directly in arboriculture, ecological restoration, landscape design, and horticulture. Subsequently, Forest Service scientists convened a workshop on how to improve the transition from green-job training to careers. They reported on lessons learned by experts, practitioners, and trainers, who participated in a panel discussion, followed by roundtable discussions, and a keynote address. They also analyzed the experiences of graduates from the program and found that these urban conservation jobs could be transformational for economically disadvantaged youth.
Contact
Products & Resources:
Urban Waters Partnership for Northwest Indiana: A Unique Collaboration
Federal and local partners work to improve local water quality and people’s access to the great (and wet) outdoors

The Northwest Indiana Urban Waters Partnership focuses on waterways with wide-ranging regional impacts. With leadership from Forest Service scientists, the federal partnership is working with local organizations concerned about waterways such as the Grand Calumet River Area of Concern, the East Branch of the Little Calumet River, Salt Creek, Trail Creek, and Deep River, and of course, Lake Michigan. Early partnership successes include 1) progress on an environmental assessment necessary to expand paddling opportunities at Indiana Dunes National Lakeshore; 2) Army Corps of Engineers modification of a dam along Deep River to facilitate paddling; 3) development of an online mapping tool (by the US Geological Survey) to allow local users to upload and map different regional information; 4) Forest Service grants awarded to three local communities to address water-quality risks caused by the loss of ash trees to the emerald ash borer; 5) restoration of 38 acres of river and upland ecosystems near Chesterton by the Army Corps of Engineers and the Shirley Heinze Land Trust; 6) exploring options for remediating water quality at East Chicago’s Jeorse Park Beach, one of the most polluted beaches in the country; and 7) providing canoe adventures for children through Wilderness Inquiry visits.
Partners
- Save the Dunes; the Cities of Gary, Hobart, Michigan City, and Valparaiso; the Northwest Indiana Paddling Association; the Steelheaders; the Counties of LaPorte, Porter, and Lake; Coffee Creek; and the Indiana Departments of Natural Resources and Environmental Management.
- United States Departments of Agriculture, Education, Energy, Housing and Urban Development, the Interior, & Transportation; Army Corps of Engineers; Centers for Disease Control and Prevention; Environmental Protection Agency; National Institute of Environmental Health Sciences; National and Community Service; National Oceanic and Atmospheric Administration; US Economic Development Administration
Products & Resources:
Conserving Biodiversity in Urban Landscapes
Working with citizen scientists to develop guidelines for conserving biodiversity in urban areas

Loss of biodiversity as a result of residential development is a national and global issue and conservation of biodiversity in urban areas is important to keeping cities livable. Forest Service scientists developed habitat relationship models to calculate the bird habitat potential of the urban forest by linking habitat relationship models with the U.S. Forest Service urban forest assessment tool, i-Tree. As part of that effort, researchers are investigating songbirds and native pollinators in yards and urban forests to understand the conditions under which they can persist and flourish in urban landscapes. Citizen “scientists” monitor the fates of color-banded birds and nests in their yards to help understand the features of yards that support viable populations. Other homeowners are participating in a project that highlights the value of delayed lawn mowing to support native pollinators and other beneficial insects. Finally, scientists are monitoring the abundance and nesting success of songbirds in forest patches and comparing these values to extensively forested areas. Using this information, we can provide homeowners and municipalities with information to guide their practices and policies to promote biodiversity from the scale of individual yards to forest conservation areas.
Partners
- Susannah Lerman
- David Bloniarz
- Keith Nislow
- Peter Marra, Smithsonian Institute; Alexandra Contosta, University of New Hampshire; Christofer Bang, Arizona State University; Scott Schlossberg, Stephen DeStefano, Joan Milam, & Paige Warren, University of Massachusetts, Amherst; & Mitch Hartley, US Fish and Wildlife Service
Products & Resources:
2012 Research Highlights
From World's Largest Landfill to New York City's Newest Park
The Fresh Kills Salt Marsh, at the southwestern corner of Staten Island in New York City, was once the world's largest landfill. Now the NYC Department of Parks and Recreation is converting the landfill into a park and a citywide cultural and recreation destination through extensive ecological restoration and landscape planning efforts. At 2,200 acres, Fresh Kills Park will be the largest park developed in New York City in more than 100 years. Forest Service researchers at the New York City Urban Field Station and throughout the NRS are working with university cooperators to explore the process of conversion and its impacts on the social and biophysical landscape. Researchers assessed Staten Island residents' attitudes toward the park, developed a communications strategy to address public health concerns about it, and used focus groups to understand residents' memories of the landfill as well as their fears and interests in using the future park. In another study, native poplar and willow plants collected from Staten Island are being propagated at the NRS Institute for Applied Ecosystem Studies in Rhinelander, WI, where they will be grown in the greenhouse and hybridized, and the most successful genotypes will be outplanted at Fresh Kills Park.
Contact
Partners
Herb Schroeder (retired), NRS; David Klenosky, Purdue University; Carrie Grassi and Eloise Hirsh, NYC Department of Parks and Recreation Fresh Kills Team; Phil Gleason, NYC Department of Sanitation; Christine Vogt, Michigan State University; Deborah Popper and Rich Flanagan, College of Staten Island
U.S. Urban Tree Cover Declining

Trees in urban areas provide many benefits to city residents. But Northern Research Station scientists have found that urban tree cover has been declining in recent years at a rate of about 20,000 acres per year or about 4.0 million trees per year. Recent analyses by NRS scientists reveal that many forces such as urban development, insects and diseases, natural regeneration, and tree planting are constantly changing the urban tree cover, both positively and negatively. Although tree cover is declining within most urban areas, the development of some urban areas can increase regional tree cover, especially in grassland-dominated states. Understanding these changes is leading to better management plans for sustaining tree cover and its associated benefits for current and future generations.
Contact
Partners
U.S. Forest Service: RPA Assessment Staff and State and Private Forestry Urban and Community Forestry Program; SUNY; National Science Foundation
More Information
Nowak, David J.; Greenfield, Eric J. 2012. Tree and impervious cover change in U.S. Urban Forestry & Urban Greening. 11(1): 21-30.
Nowak, David J.; Greenfield, Eric J. 2012. Tree and impervious cover in the United States. Landscape and Urban Planning. 107: 21-30.
News Release: Nation's urban forests losing ground: New Orleans, Albuquerque, Houston losing trees
More Trees Associated with Less Crime in Greater Baltimore

Northern Research Station scientists found a strong inverse relationship between tree canopy and crimes of robbery, burglary, theft, and shooting when they compared high-resolution tree canopy data and geocoded crime point data in the Baltimore region. These findings add to the literature on the relationship between crime and vegetation in a number of ways. First, the findings show that where there are more trees there is less crime. Second, this result holds for both public and private land, but it is stronger for public land. Third, when spatial autocorrelation is adjusted for, the overall result still holds, but the magnitude is not as great. Finally, it appears there is some slight geographic variability in the relationships between trees and crime and that a few isolated areas see a positive relationship between trees and crime. The modeling results indicated conservatively that a 10 percent increase in tree canopy was associated with a roughly 12 percent decrease in crime.
Contact
Partners
Austin Troy, University of Vermont
More Information
Troy, Austin; Grove, J. Morgan; O'Neill-Dunne, Jarlath. 2012. The relationship between tree canopy and crime rates across an urban-rural gradient in the greater Baltimore region. Landscape and Urban Planning. 106: 262-270.
Understanding Urban Civil Environmental Action Across the U.S.

Visualizing where and how hundreds of civic environmental stewardships groups are working in cities across the United States has gotten easier for the public, municipal agencies, and nonprofits, thanks to the continued work of the Stewardship Mapping and Assessment Project (STEW-MAP). STEW-MAP, developed by scientists from the Northern Research Station, supports urban natural resource management, policymaking, and public outreach with databases and interactive maps. This year, the STEW-MAP team continued to expand the project's geographic reach as well as its products and platforms. The team has launched a new multi-city online portal (http://stewmap.net/), which provides information about STEW-MAP projects in New York City, Chicago, Baltimore, and Seattle, including maps, network diagrams, and publications to date.
Contact
Partners
Dale Blahna, Kathy Wolf, PNWRS; Dana Fisher, University of Maryland; James Connolly, Northeastern University; Dexter Locke, NRS/New York City Department of Parks and Recreation; Steve Romalewski and Christy Spielman, CUNY Center for Urban Research; Oliver Bazinet, University of Washington; Mark Bouman, Field Museum
More Information
Fisher, Dana R.; Campbell, Lindsay; Svendsen, Erika S. 2012. The organisational structure of urban environmental stewardship. Environmental Politics. 21(1): 26-48.
Connolly, James J.; Svendsen, Erika S.; Fisher, Dana R.; Campbell, Lindsay K. 2013. Organizing urban ecosystem services through environmental stewardship governance in New York City. Landscape and Urban Planning. 109: 76-84.
2011 Research Highlights
Culturally Appropriate Conservation Education for the Hmong American Community
Forest Service researchers produced a conservation education DVD in partnership with the Hmong community titled “The Wildlife and Wilderness Exploration Show.” The DVD puts a modern twist on traditional Hmong storytelling, delivering key messages in entertaining and educational segments covering a wide range of topics. The educational messages were identified through interviews with Hmong natural resource professionals across the US.
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Street-Level Views of Climate Change
Forest Service researchers and partners interviewed residents of two Chicago neighborhoods about their awareness of climate change and their own climate-friendly behaviors. They found that residents have varying levels of knowledge about climate change and identified many opportunities to simultaneously meet neighborhood goals and mitigate the impacts of climate change. The findings will help the City of Chicago shape its Climate Action Plan outreach to residents and the lessons learned are applicable in other places as well.
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Five Years after the Fire, Effects on Community Still Linger
Persistant long-term effects of wildfire can limit community recovery years later
Organizations helping communities recover from the effects of wildfire need to understand the issues and conditions that are likely to persist even years later. In this study of communities affected by the Rodeo-Chediski fire five years after the event, Forest Service scientists and their university colleagues found that although the community took some positive actions in response to the fire, other negative impacts persist.
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Non-native Forest Pathogens Cost Homeowners Millions of Dollars Annually
Two big killers of residential trees--the oak wilt pathogen in the East and the sudden oak death (SOD) pathogen in the West cost homeowners millions of dollars annually. Millions are spent to treat, remove, and replant oak trees and millions are lost in property value where ever these diseases have spread. Forest Service researchers calculated economic costs and losses to homeowners and communities and found that programs to slow the spread of forest diseases such as oak wilt and sudden oak death provide important benefits, in terms of reduced expenditures and losses, to both homeowners and communities.
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2010 Research Highlights
Urban and community forest summaries for the lower 48 States
NRS scientist David Nowak and others have recently published several important summaries of tree and forest information. The first is a summary and comparison of urban tree cover and its associated benefits in the lower 48 United States, Sustaining America’s Urban Trees and Forests (GTR-NRS-62). The second is a compilation of tree and impervious cover data and population statistics for each of the lower 48 United States (in seven publications, GTR-NRS- 38, 47, 50, 54, 56, 58, & 59) using National Land Cover Data (NLCD) and U.S. Census data.
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Fungicide treatment alters wood anatomy and suppresses oak wilt
Oak wilt, a devastating fungal disease of mature trees in rural and urban forests of the eastern and southern U.S., is spread by insects that visit tree wounds (including pruning cuts) and also travels through natural root system grafts. Injection of the fungicide propiconazole in the root flares has been standard commercial practice by arborists, who have found that retreatment is necessary after several years. NRS scientist Jennifer Juzwik, in collaboration with the University of Minnesota and a commercial arboriculture company, found that injected propiconazole in the tree roots and lower stem degraded below levels required to stop the disease fungus after two years.
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Models for ecological restoration in urban areas: Lessons from the USA and Europe
Ecological restoration often aims to recreate so-called pre-settlement conditions, but this can be problematic in urban areas where human activities have erased most traces of pre-settlement conditions. NRS researchers Paul Gobster and Lynne Westphal and a German colleague, Matthias Gross, analyzed urban restoration projects and developed several alternative models that articulate the various possible types of restoration projects.
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Perceptions of crime and its impacts on the use of urban parks by Latino residents
Perceived safety has long been known to play an important role in people’s use of urban parks, but little is known about how the everyday leisure behavior of neighborhood residents is altered by the presence of gang activity. NRS scientist Paul Gobster examined how the perceptions of Latino residents in two inner- city Chicago neighborhoods affected their use of outdoor recreation environments and how they responded.
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2009 Research Highlights
Restorative Commons
The Northern Research Station (NRS) published the proceedings
of a conference titled Restorative Commons: Creating Health
and Well-being through Urban Landscapes. Participants at the
2007 conference shared lessons learned from the fields of
urban natural resource management and design with other
practitioners, policymakers, and the general public.
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Urban tree canopy: The development of prioritization tools
Scientists from the Northern Research Station, the University
of Vermont (UVM) Spatial Analysis Laboratory, and other
partners have developed tools for the high resolution
assessment of urban landcover. These tools have been applied
to a range of cities, including Burlington, VT; Boston, MA;
New York City; and Baltimore and Cumberland, MD. Based
upon these assessments, these cities have established urban
tree canopy (UTC) goals and allocated resources to meet
these goals.
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Protecting habitat for grassland birds also improves life for people
More than 80 percent of the U.S. population lives in urban
areas, and these areas are experiencing rapid growth and largescale
development of open space. Many residents are concerned
about the loss of open spaces and the amenities they provide,
and many local organizations, including local governments,
have policies and funds to acquire land or conservation
easements within or on the fringe of metropolitan areas.
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Listening to neglected voices
Natural resource managers need to understand the cultures
and concerns of ethnic minority communities to serve
them effectively. The Hmong people from Southeast Asia
came to the U.S. as refugees after the Vietnam War.
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Tree biology education for landscape professionals
Urban and community forests need arborists and other landscape
professionals who understand the relationship of tree biology and
the environment.
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2008 Research Highlights
Fight crime: Plant a tree
Trees and green space have always been prized in urban settings for their aesthetic value. But their stock might go up after a recent study suggests vegetation management might also affect crime rates.
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2007 Research Highlights
Tree software benefits cities and their trees
NRS staff completed analyses of urban forest structure and ecosystem services and their values for seven U.S. cities
and four cities in Italy. Using the Urban Forest Effects (UFORE) model, these cities
were able to quantify the value of their existing forest cover and identify the potential
for increasing canopy cover and value to the city.
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Living Memorials Project honored
The NRS’s Living Memorials Project received
top honors from the Environmental Design Research Foundation and Places Journal
and from the Voices of September 11th organization this year for its documentation of
the spaces people create or use as they shape the landscape to memorialize
individuals, places, and events.
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Wildland-urban interface maps aid fire planning
The 2007 southern California
wildfires generated demand for the detailed maps of the wildland-urban interface
(WUI) generated by NRS scientists and collaborators. California land managers and
policymakers used the spatial detail of the maps in their efforts to protect 5.1 million
WUI housing units (the nation’s highest number).
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