Urban Forestry: The Position of the Society of American Foresters

Position

The Society of American Foresters (SAF) believes actions and practices that strengthen and improve the urban and community forestry discipline within the broader profession of forestry are vital to the social and economic well‑being of the nation. The SAF strongly supports activities and funding levels that promote the establishment, maintenance and sustainability of healthy urban forest ecosystems for all urban communities. The SAF supports integrating the science and art of urban forestry into urban land use planning systems and related commitments.  Urban and community forestry is a viable and complementary component of managing the nation’s forest ecosystems and a viable part of urban ecosystems. Urban forestry also improves the quality of life in urban areas. Prior to the establishment of an urban forestry program, a socioeconomic analysis needs to be done of the area and community involved. After implementation, a monitoring and evaluation plan should be developed to ensure program objectives are being met.

The Society believes that the sustainable management and use of urban forest resources requires appropriate policy, a modest regulatory framework, and forward-looking research and investment programs, as well as institutional strengthening to make government and private sector investments and partnerships in urban and community forestry more effective and efficient. The ultimate success of such programs will also depend upon the efforts of individual citizens from all ethnic and socioeconomic levels who, on a voluntary basis, participate with local, state, and federal governments to ensure program objectives are met.

Issue

It is highly uncertain as to whether existing programs throughout the nation will meet the increasing demand by the urban communities; and whether sufficient financial support and long-term commitments exist for managing urban forest ecosystems sustainability.  Some of the concerns include unplanned intrusion and lost opportunities for design in urban sprawl, a lack of funding and need for the preservation of unique forest characteristics. 

Urban and community forestry play an important role in enhancing urban environmental quality by providing a multitude of benefits such as enhanced aesthetics; improved air, water and soil quality; increased recreational opportunities; improved physical and mental health; and community strengthening and pride. Societal benefits associated with urban and community forestry are opportunities for forest resources education and economic and community betterment and development.

Background

Urban forestry is the integrated biophysical management of urban forest ecosystems for improving the quality of life (SAF B2 WG 2002). This includes the art, science and technology of managing trees and forest resources as an integral part of urban community ecosystems for physiological, sociological, economic and aesthetic benefits.

Urban and community forests are made up of trees and associated vegetation within the environs of populated places – from the smallest villages to the largest cities. Such forests involve trees along streets, within greenbelts, greenways, parks, public spaces, residential yards and neighborhoods, municipal watersheds, and other areas. There are 70 million acres of such forests in the nation in communities where 80 percent of our citizens live, work and play. The unique demands on urban forests, their location within heavily populated and developed areas, and their potential as a medium to educate and engage the public in natural resource issues require unique management approaches. A recent assessment by the USDA-Forest Service indicated the extent and importance of our nation’s urban forest (Dwyer et.al. 2000).

Urban forests provide a multitude of benefits, including the reduction of energy costs through summer shade and winter wind protection (Akbari et.al. 2001, McPherson et.al. 1993,  Laverne 1996). Summertime studies have shown a 1° to 2°F (0.5° to 1.0°C) decrease in temperature for every increase of 10 percent vegetation cover (Nowak et al. 1994). Houses shaded by trees need 4 to 25 percent less energy for cooling than those in the open. Homes sheltered from the wind have winter heat savings of as much as 10.3 thousand BTUs or approximately $52 annually (Nowak et al. 1994). Urban trees will continue to be increasingly important for their energy-saving value as fossil fuels become more scarce and more expensive in the future and as the impacts of global climate change occur.

Additional benefits of urban forests include slowing and reducing stormwater runoff, flooding and erosion, thus reducing potential sources of water pollution. Tree foliage works as a natural air filter of particulate matter and pollutants such as ozone, nitrogen oxides, ammonia, and sulfur dioxides (Abdollahi et.al. 2000).  Foliar filtration, when combined with the intake of carbon dioxide and the production of oxygen through photosynthesis and the natural cooling effects of evapotranspiration, can have a significant effect on smog and reduce overall air pollution. The cooling effects of trees help reduce the need for utilities to increase power generation capacity to meet peak energy load demand. Consequently, less CO₂ is produced and energy savings are passed along to the public (Abdollahi, et.al. 2000). Nationally, between 400 and 900 million metric tons of carbon are stored in the country’s urban forest (Nowak et al. 1994). Urban and community forests directly increase property values, therefore making communities more attractive to tourists and industry (Morales 1980).

Whether or not to develop, support, or enhance urban and community forestry programs should not, however, be based solely on economic criteria. While studies have revealed potential benefits of urban forests to human physical and psychological health (Ulrich 1984, Lohr 1996) and to community stability and crime reduction (Kuo, et. al. 2001), the aesthetic value of trees and urban forestland constitute solid justification on their own.  Accessible green open space has been found to reduce the chronic mental fatigue of urban life (Kuo, et. al. 2001). Trees, shrubs, and related plants are valuable community assets that enhance neighborhood beauty, recreational opportunities and wildlife habitat, and also provide city dwellers with opportunities to experience and understand forest‑related benefits (Kuo, et. al. 2001). These opportunities in turn, help them to understand and better appreciate the value of the nation’s rural forest resources and their management.

Establishing and maintaining urban and community forests requires an investment of significant resources in community infrastructure (Dwyer, et. al. 1992). Unlike a timber harvest operation where seedlings are used to reforest an area, urban forestry deals almost exclusively with larger saplings and full-grown trees. This difference arises because of the high mortality rate and theft of seedlings in urban areas. The effect of using larger planting stock is the greater cost per tree (Urban Resources Initiative 1995).

One cost important to factor into program funding is the annual maintenance cost per tree. This becomes very important, particularly when considering such needs as utility line clearance, storm damage repair, debris removal, and protection from various pathogens. Because of the increasing financial crises faced by American cities, the planting and maintenance of urban forests has decreased dramatically, to the detriment of these communities. Communities can reduce some of these costs by proper selection and location of trees to avoid future problems. Unfortunately, many communities lack the information and funding necessary to make correct planning decisions. Urban forests and tree programs, therefore, deserve our sustained support through adequate funding for good planning and implementation to protect and maintain them as integral components of urban ecosystems and the nation’s overall forest estate.

The Government Accounting Standards Board (GASB) Ruling 34 helps capture the capital represented by the natural environment.  Until Ruling 34 it was ignored or assumed to be prices at zero dollars.  Ruling 34 captures these hidden assets for bond markets to take into account in underwriting municipal bonds.  Including ecosystem services into municipal accounting systems will provide for long term maintenance of this natural capital asset at the municipal level.

Urban and community forests are an appreciating resource asset estimated to have a value of nearly $30 billion. This value lies primarily in their aesthetic contribution to urban and community landscapes. Value also includes contributions to the quality of life through moderating temperatures; improving air, water, and soil quality and management; increasing employment opportunities; creating community cohesion; reducing crime; and improving human physical and mental well being. Community trees and forests can help maintain air quality standards, thus helping communities avoid nonattainment status that would otherwise reduce their municipal bond rating and their ability to engage in continued development. While difficult to quantify, these attributes are important, positive societal benefits of establishing and maintaining healthy urban and community forests.

Long-term planning, appropriate tree species selection, care and management practices, and establishing local budgets that allow municipalities and communities to avoid crisis management (characterized by unhealthy forests and damage litigation) and favor lower costs for forestry programs in urban settings. Costs of urban and community forest management under planned and efficiently administered systems are far outweighed by benefits accrued to the public and the community at large.

Coordination among federal, state, and local governments; non-profit organizations; educational institutions and jurisdictions on planning and management of our urban and community forest resources are essential to the success of these efforts. Creating opportunities and meeting the wishes of communities to improve their natural resources and forest environments will help engage and educate the public to improve the quality of life for all citizens.

References Cited

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