Enhancing the Benefits of
South Carolina’s Trees and Forests
This section describes the role of community forests in South Carolina as well as the benefits that forests and trees provide in protecting the quality of air and water in the state.
Water Quality and Quantity
Stakeholders indicated that water quality and water quantity were high priority issues. Surface water that is free from pollutants and sediment and provides habitat requirements for wildlife is considered to be of high quality. Water is a critical resource affecting all aspects of quality of life, from health and recreation to economic development.
Managing forests and trees has the potential to impact water quality and water availability throughout the state. South Carolina is 67 percent forested land, and a significant portion of the state’s water resources are linked to healthy forests.
Compared to other land uses, the negative impacts of forest management activities on water quality are minor, with silviculture the lowest leading source of impairment in Southern states. Timber harvesting is viewed by some as a source of water pollution, but normally leaves understory and organic material in place, and results in little disturbed or exposed soil (USFS 2002). In general, forests produce the highest water quality and most stable streams of any land use (Myers et al. 1985).
Sediment is typically the greatest nonpoint source pollutant. The average annual sediment yield from land in the southeast is 1.3 tons per acre.
Table 6: Sources of Sediment by Land Use Type
Sediment Yield (tons/acre/year)
trace - .32
.06 - .17
|Mechanical Site Prep||
5.60 - 6.36
.42 - 7.50
7.80 - 43.06
48.40 – 218.91
(Source: Yoho 1980)
Several classifications may indicate desirable water quality. These include state and federally designated scenic rivers, Outstanding Resource Waters, and waters supporting threatened and endangered aquatic wildlife. Trout waters and source drinking water further indicate quality water resources that may need special management considerations. Headwater streams are especially important for water quality, and isolated wetlands present unique habitats for biodiversity.
The greatest risk of impact from forestry operations is typically sediment from roads and stream crossings. Failure to follow Best Management Practices (BMPs) in riparian areas can result in increased turbidity or sediment, water temperature, nutrient levels, and lowered dissolved oxygen. Most water-quality impacts are temporary or short-lived, are minimized or mitigated when BMPs are applied, and the site recovers within two to three years as vegetation grows (USFS 2002). Maintaining forested land use and application of BMPs is important in riparian areas to maintain the current high standard of water quality. BMPs are designed to address most conditions, but adjustments are sometimes needed for waters with high richness or uses.
Although negative water quality impacts from forestry are minor, some forestry activities can have a significant impact if not carried out properly. Considerable research has shown use of Best Management Practices to be successful in controlling and preventing nonpoint source pollution during forestry activities (USFS 2002).
The SC Forestry Commission is the state agency designated to provide oversight and guidance for forest management practices and to establish BMPs for forestry. The agency provides educational opportunities and technical assistance through a BMP Courtesy Exam program designed to improve compliance and implementation. The forest industry in South Carolina has a strong commitment to support logger compliance with BMPs.
The BMP Courtesy Exam program offers free services to identify potential environmental impacts from forestry operations. Specially-trained BMP Foresters visit sites before, during, and after operations to offer recommendations and ensure applicable BMPs are being followed. Courtesy exams are initiated on request, but sites may also be located by complaint, incident, or through aerial detection. Failure to implement BMPs may result in regulatory violations that are reported to the appropriate enforcement agency for possible action. In addition, forest industry will often take action when suppliers fail to comply with BMPs. Many mills will not accept wood from loggers who have been cited for failure to comply with BMPs.
Overall compliance with South Carolina’s Best Management Practices for Forestry is 98.6 percent for timber harvesting operations. This indicates that the South Carolina BMP Program is highly successful, and that landowners, loggers, and forestry professionals demonstrate a strong commitment to protecting water quality (Sabin 2009). The regional average among 13 southeastern states for overall BMP compliance during harvesting is 89 percent (SGSF 2008). Harvesting compliance in South Carolina has shown continual improvement since the first monitoring study was started in 1989 (see Figure 19).
From Compliance and Implementation Monitoring of Forestry Best Management Practices for Harvesting in South Carolina, 2007-2008.
The SC Forestry Commission provides further assistance to help landowners protect water quality by providing forest management plans, cost-share assistance, and reforestation advice. Commission foresters routinely offer information on all aspects of resource management, including BMPs. South Carolina’s BMPs for Forestry are applicable for all silvicultural activities, with specific guidelines for timber harvesting, road construction, stream crossings, riparian buffers, wetlands, site preparation, reforestation, prescribed burning and firelines, pesticide and fertilizer application, wildlife improvements, and minor drainage.
The SC Department of Health and Environmental Control (DHEC) have identified areas with significant threats to water quality. These designations are based on the state 303(d) listing of impaired waters and watersheds with current or in-process Total Maximum Daily Loads (TMDLs)1. Impairment may result from a wide range of sources and pollutants. Although none of these impaired areas in South Carolina are directly linked specifically to forestry activity, opportunities may exist to mitigate or buffer impacts from other uses by using forested buffers. In these areas forest management can capture, absorb, detain, or retain pollutants and contribute to cleaner, healthier water.
Watershed features can also affect water quality. Certain features can lead to greater risk of negative impacts and suggest the need for additional attention. Past land uses are sometimes a consideration, especially where they have left the surface eroded, gullied, and/or barren. Other features to address include slope, erodible soils, riparian areas, and wetlands. Occurrence of these features may indicate a higher potential for negative impacts from forestry activities. Evaluation of the water quality indicators previously mentioned provides additional knowledge on watersheds that warrant prioritization to conserve high quality water resources, mitigate impaired water quality, and support areas where threats are greatest.
Managing water resources is the responsibility of many state and federal agencies, and is the focus for many other organizations, businesses, and citizens. For example, the SC Forestry Commission has a Memorandum of Agreement with (and regularly cooperates with) the US Army Corps of Engineers on silvicultural water quality issues under jurisdiction of the SC Pollution Control Act and Clean Water Act. In addition, the Forestry Commission’s BMP Courtesy Exam Program is supported by a US EPA Section 319 grant administered by DHEC.
An issue of such wide-ranging importance to both society and the environment requires an interdisciplinary and multi-jurisdictional approach involving many partners and stakeholders. For example, the SC Forestry Commission provides technical expertise, experience, and resources on the role of forestry in water quality. The agency can also seek new partnerships and strengthen communications with existing partners to focus on water issues within the state. In addition, the Commission can promote the use of tree cover and forest management to protect water quality and streambank stability from adjoining land uses.
A closely-related, high-profile subject has been water quantity and availability. In recent years, related issues have included water rights, reservoir management, in-stream flow needs, and drought. Industrial, agricultural, and human consumption of water are often at odds, competing for limited available resources. Indigenous aquatic life and other beneficial water uses are also considerations.
South Carolina has an abundant supply of freshwater, but is not immune to water quantity issues. Inter-basin transfers and years of drought have led to disputes with neighboring states over water use. Most of South Carolina’s major rivers are shared with North Carolina and Georgia. Dams, diversions, canals and other hydrologic modifications alter the natural path of water, creating varied positive and negative effects to ecosystems and society. Groundwater supply is also an issue, especially in the coastal plain. Surface and groundwaters are connected, but with varying degrees of intensity relative to recharge and discharge.
Although forests play an important role in providing clean water, issues of water quantity are largely beyond the traditional scope of the SC Forestry Commission. However, forests provide most of the available potable water and serve as the most efficient water filters. With responsibility for overall forest resource management in South Carolina, the SC Forestry Commission has a role to play in helping protect water quality. Timber harvesting can result in increased water yield for several years until new growth is established. Depending on the circumstances, conversion of forests or cover types may increase or decrease stream flow. Where ownership and goals within a watershed match, forest management can be used to affect water yield. With adequate funding, the SC Forestry Commission would be in a good position to highlight the types and persistence of water yield changes that can occur in connection to forests and their management and lead in managing the impact of forests on water quality and quantity.
Opportunities for the SC Forestry Commission also include additional work with partner agencies and emphasis on the importance of forestry for sustained water resources, conservation, and stewardship.
Literature Cited and References
Hibbart, A.R. 1965. Forest treatment effects on water yield. International Symposium on Forest Hydrology. W.E. Sopper and H.W. Lull (eds.). Pergamon Press. New York. pp. 527-543.
Sabin, Guy. 2009. Compliance and implementation monitoring of forestry best management practices for harvesting in South Carolina, 2007-2008. 37 pp. Available online at http://www.state.sc.us/forest/bmp07.pdf
Southern Group of State Foresters (SGSF) Water Resources Committee. 2008. Implementation of forestry
best management practices – A Southern Region Report.
South Carolina Forestry Commission (SCFC). 2010. South Carolina’s best management practices for forestry. Available online at http://www.state.sc.us/forest/menvir.htm
Swank, W.T., L.W. Swift, Jr., and J.E. Douglas. 1988. Streamflow changes associated with forest cutting, species conversions and natural disturbances. Ecological Studies of Forest Hydrology and Ecology at Coweeta. W.T. Swank and D.A. Corssley, Jr. (Eds). Springer-Verlag.
USDA Forest Service (USFS). 2002. Southern forest resource assessment. Gen. Tech. Rep SRS-53.
Yoho, N.S. 1980. Forest management and sediment production in the south – A Review. Southern Journal of Applied Forestry. 4(1):27-36.
1TMDL – Total Maximum Daily Load - written quantitative analysis of water quality for a pollutant at one or more sites in a watershed. (Source: DHEC – available online at http://www.scdhec.gov/environment/water/regs/r61-110.pdf)
Air Quality is defined as a measurement of the pollutants in the air; a description of healthiness and safety of the atmosphere (Dictionary 2010). South Carolina’s forests play a major role in filtering the air of pollutants (in other words, ozone and particulate matter), but can act as a source of particulate matter when wildfires rage through them. Forestry practices such as prescribed burning can reduce these fuel loads, thereby reducing the negative effects of wildfires. The forests also respond positively to carefully planned and executed prescribed burning with improved growth as competition for sunlight, water, and minerals is reduced.
Trees sequester atmospheric CO2 through the process of photosynthesis. This sequestration exceeds the CO2 emissions generated by events such as forest harvests, land conversions, and fires. Methane from forest fires amount to about 5 percent of the total. Forest fires also produce about 1 percent of the total nitrous oxide emissions. Forest fires in this context include prescribed burns and wildfires (USFS 2007).
New housing developments often lead to increased levels of air pollutants. For example, as the population grows and industry moves in to meet the population’s needs, increased levels of air pollutants such as sulfur dioxide, nitrous oxide and mercury are emitted into the atmosphere. In South Carolina, attainment levels for sulfur dioxide and nitrous oxide are met due in large part to strict air quality regulations. Landscaping with trees around industrial sources of pollution can help filter such pollutants, thus reducing the negative impacts on air quality (Tommy Flynn, pers. comm., SC Department of Health and Environmental Control (DHEC), January 6, 2010).
Other sources of air pollutants include vehicles. However, with new emissions equipment and standards, the quantity of these pollutants has actually been decreasing. And, with active urban forestry programs where tree planting and arbor care are implemented, additional reductions in the pollutants released by vehicular emissions can be achieved.
Urban tree plantings can also play a significant role in energy conservation especially in metropolitan areas where population densities are greatest. Trees tend to decrease the temperatures around these heat sources, resulting in less ozone being produced.
DHEC monitors air health impairments, non-attainment areas1, and inversions. York County is the only area within the state that currently has non-attainment issues (Tommy Flynn, pers. comm., DHEC, January 6, 2010).
South Carolina has an average of 2,791 wildfires per year that burn a total of approximately 20,000 acres. The Southern Wildfire Risk Assessment is being used along with SC Forestry Commission historical records to classify and identify those communities at-risk to support wildfire planning and protection efforts. At the state level, the assessment is being used to increase awareness of the fire problem in South Carolina and to help the public understand fire management issues (Andreu et al. 2008).
Prescribed burning is one forest management tool used by forest managers to help reduce the hazardous fuel buildups that often accumulate in the forest lands around South Carolina. By conducting prescribed burns, fuel buildups are reduced lessening the chance of a disastrous wildfire. Prescribed burns also burn less intensely, produce less particulate matter and, therefore; have less of an impact on the atmosphere than wildfires (Hessburg and Agee 2003).
The South Carolina Smoke Management Guidelines provide for minimizing the impact of smoke from vegetative debris burning operations for forestry, agriculture, and wildlife purposes. To do this, the Guidelines define smoke sensitive areas, amounts of vegetative debris that may be burned, and atmospheric conditions suitable for burning this debris. The SC Forestry Commission is responsible for administering the Smoke Management Guidelines. In doing so the Commission consults with and coordinates activities with the National Weather Service and the South Carolina Department of Health and Environmental Control (DHEC-Air Quality Division) to ensure compliance with air quality standards as outlined in the Memorandum of Understanding (SCFC 2006).
Prescribed burns and wildfires are a source of ozone and smoke (particulates). These pollutants have the greatest impact on air quality. Human activities are the primary cause (98 percent) of wildfires in South Carolina with about 40-45 percent due to escaped debris burns. This cause alone accounts for approximately 1,300 wildfires burning 8,400 acres per annually. A reduction in the number and size of human-caused wildfires can help reduce the negative effects on air quality (SCFC 2010a).
In South Carolina, forest managers prescribe burn an average of 527,000 acres annually (FY05 – FY09) for wildlife, forestry, and agriculture purposes. These prescribed burns are managed so that they produce limited amounts of smoke as compared to wildfires. The state’s Smoke Management Guidelines limit the amount of burning which can take place depending on how well the smoke will be dispersed that day (SCFC 2006).
It is unusual for ozone problems to occur during the prescribed burning season (late winter through spring), but can be a problem with summer wildfires when ozone levels are higher. Ozone is created during the combustion of nitrous oxide. High summer temperatures combined with burning of forest fuels can result in elevated amounts of ozone. In the last five years ozone levels have decreased due in large part to tighter emissions controls on power plants and automobiles. The outlook is for continued improvement helped by new and more stringent standards that will be implemented by the EPA sometime in 2010.
Particulate Matter, (PM 2.5) is measured in micrograms and since 2003 has been decreasing. This decrease in atmospheric particulate matter, especially over the last couple of years, may also be due in part to the downturn in the economy. (Tommy Flynn, pers. comm., DHEC, January 6, 2010). However, data is limited as there are only a dozen air quality stations statewide.
Contributing to the amount of ozone produced are approximately 320,000 yard debris burns, as well as burns associated with the clearing of land for development and the maintenance and installation of highway rights-of-way. These burns are not regulated by the Smoke Management Guidelines, but are restricted by DHEC Regulation 61-62.2 – Prohibition of Outdoor Burning (SCFC 2006).
When prescribed burning is conducted in the wildland–urban interface (WUI), the smoke that is produced can sometimes inconvenience people, and it can also cause serious health and safety problems. The public is unlikely to continue to tolerate the use of prescribed fire, regardless of the benefits, if burn managers cannot keep smoke out of smoke–sensitive areas (Wade et al. 2007, p.i).
Negative public reaction to smoke generated by prescribed and debris burns can lead to the passage of ordinances such as county–wide burn bans. Such burn bans may not consider the positive effects of prescribed burning. Therefore, they should be carefully scrutinized to ensure that forestry, wildlife and agriculture burns are exempt from such ordinances. The SC Forestry Commission’s continued collaboration with DHEC will keep the forestry, wildlife and agriculture burns in mind as regulations affecting air quality are pursued.
The SC Forestry Commission’s urban and community forestry grants provide opportunities for communities to address the care of urban forests and plan for green space to help offset the negative impacts of urban developments on air quality. For example, these grants provide funds for maintenance of the urban trees which absorb significant amounts of air pollutants and reduce surface temperatures. Refer to the chapter on community forests in South Carolina for additional information.
Literature Cited and References
Andreu, A. and L.A. Annie Hermansen-Baez. 2008. Fire in the south 2: the southern wildfire risk assessment. Southern Group of State Foresters. Available on line at www.southernwildfirerisk.com/reports/FireInTheSouth2.pdf.
Dictionary.com, LLC copyright 2010. Definition of air quality is available online at http://dictionary.reference.com
Hessburg, Paul F. and James K. Agee. 2003. An environmental narrative of inland northwest United States forests, 1800-2000. Forest Ecology and Management 178: 23-59.
South Carolina Forestry Commission (SCFC). 2010. Available online at http://www.state.sc.us/forest/bweather.htm
South Carolina Forestry Commission (SCFC) Annual Reports. 2010a. Available online at http://www.state.sc.us/forest/ar.htm
South Carolina Forestry Commission (SCFC). 2010b. Benefits of urban trees. Available online at http://www.state.sc.us/forest/urbben.htm
South Carolina Forestry Commission (SCFC). 2006. Smoke management guidelines for vegetative debris burning operation in the state of South Carolina. Publication includes the Memorandum of Understanding between DHEC and the Forestry Commission (p.14), DHEC Regulation 61-62.2 (p.15), and the Air Stagnation Advisory and Ozone Alert (p.5). Available online at http://www.state.sc.us/forest/smg05.pdf
Strom Thurmond Institute. Clemson University. 1998. The South Carolina prime lands initiative. Available online at http://www.strom.clemson.edu/primelands/
US Census Bureau. Population Division. 2005. South Carolina 2030 population projections. Available online at http://www.sccommunityprofiles.org/census/sc_proj.php
Matthews, Anthony. 2007. Wildland fire emissions in the EPA inventory of U.S. greenhouse gas emission and sinks: 1990-2007. USDA Forest Service. 4 pp. Available online at http://epa.gov/climatechange/emissions/usinventoryreport.html
Wade, D. and H. Mobley 2007. Managing smoke at the wildland–urban interface. USDA Forest Service Southern Research Station. USDA For. Serv. Gen. Tech. Rep. SRS-103. 28 pp.
1non-attainment areas - areas where the amount of ground-level ozone exceeds the EPA standard of 0.075 parts per million
Community Forests in South Carolina
The community forest is the aggregate of all vegetation and green spaces within populated places. Community forests are an integral part of cities, subdivisions, streets, residential yards, parks, and open spaces. This urban forest provides benefits and values vital to enriching the quality of life where South Carolinians live, work and play. Properly cared for and well-managed community forests can provide economic and social value that far exceeds their management costs.
Community forestry is the combination of planning, establishing, and managing trees and associated plants (individually, in groups, or under forest conditions) within cities, towns, suburbs and military bases. Community forest management addresses the interface between people, the built environment and trees through a dynamic interaction of various professions including forestry, horticulture, arboriculture, landscape architecture and urban planning.
As our cities continue to grow in population and land coverage, community forest management is critical for healthy and sustainable living. Essential components of a well-managed and fully integrated program include fulltime staff and equipment, tree management and zoning policies, a tree inventory and management plan, a sustained budget and local political support.
Approximately 100 communities, representing 2.5 million South Carolinians, have some level of tree management. The Community Forestry program tracks, classifies and assists these communities into three distinct management levels as defined by the USDA Forest Service requirements for receiving federal funds for the state program implementation. These levels are: managed, developing and non-participating. A managed community is one that has established all of the following: a fulltime professional staff position, a management plan, tree policy, and an advocacy group. A developing community is one that has established one to three of the above listed components. A non-participating community is one that has not yet established any of the above listed components. Listed below are the definitions for and examples of the program management components.
Professional Staffing: An individual who has one or more of the following credentials, and who the community directly employs or retains through written agreement to advise and/or assist in the development or management of their urban and community forestry program: 1) a degree in urban forestry or a closely related field (e.g., forestry, horticulture, arboriculture, etc.), and/or; 2) International Society of Arboriculture Certified Arborist (ISA) or equivalent professional certification.
Management Plan: A detailed document or set of documents developed from professionally-based inventories/resource assessments that outline the future management of the community’s trees and forests. Examples of management plans include: Urban Forest Master Plan, Public Tree Planting and Maintenance Plan, Comprehensive Land Use Plan that incorporates specific management recommendations for the community’s trees and forest resources, and a Hazard Tree Reduction and Replanting Plan based on an inventory of community trees.
Ordinance/Policy:Statutes or regulations that direct citizens and local governments in the planting, protection and maintenance of urban and community trees and forests. Examples include: Public Tree Care and Maintenance Ordinance, Tree Preservation and Landscaping Ordinance, Watershed Protection Ordinance, and Tree Conservation and Tree Warden Ordinance.
Advocacy/Advisory Organization: An organization that is formalized or chartered to advise (organizations established by the local government) or advocate or act (non-governmental organizations active in the community) for the planting, protection and maintenance of urban and community trees and forests.
Approximately 25% of incorporated municipalities (>1,000 in population) live in a managed community. This represents 760,832 South Carolinians. Approximately 54% of incorporated municipalities (> 1,000 in population) live in a developing community. This represents 1,673,440 South Carolinians.
The goal of the SCFC’s Community Forestry Program is to create, enhance and support long-term local, regional and statewide community forestry programs. To accomplish this, the community forestry staff provides state-wide technical and educational assistance regarding the components listed above as well as tree inventories, grant project implementation, tree and utility line issues, and air and water quality issues. Additional services offered include Tree City USA and Tree Campus USA implementation, proper tree selection, installation, care and maintenance, distribution of educational information, coordinate and conduct training workshops, and Arbor Day/Earth Day activities. Primary assistance is provided to personnel working for towns, cities and counties. Secondary assistance is provided to professional associations, civic and volunteer organizations, state agencies, educational institutions, businesses and others.
Up until January 2010, the Community Forestry Program has also provided financial assistance to a wide array of entities in the form of 1-to-1 cost-share grants. Over the past 18 years, the program awarded approximately $4.5 million dollars to over 620 municipalities, counties, non-profit organizations, state agencies and educational institutions across the state. There are four basic categories which are available for funding: Community Forestry Program Development, Community Forestry Program Improvement, Information & Education and Public Tree Planting.
These grants have not only helped establish most of the municipal forestry programs that exist today and cited above but have also provided funding for thousands of trees to be planted in public spaces and have helped provide the skill set needed for those charged with public tree management. Hundreds of local government and university tree managers have been able to attend urban forestry and arboriculture related educational events and at least a dozen folks have become ISA Certified Arborists or Municipal Specialists through this program. This educational and accreditation assistance is not available through any other state agency.
During 2009, SCFC community forestry staff provided technical, educational and/or financial assistance to approximately 60 local government entities with a collective population of 2,434,272 citizens.
This type and availability of assistance described above is very specialized and is only provided by the Forestry Commission. No other public agency fills this much needed niche. While the potential and need for the Community Forestry Program to impact many more communities and SC citizens exists, the optimal resources to do so do not.
One of the tools used to engage and initiate community forestry management within municipalities is Tree City USA program (http://www.arborday.org/programs/treeCityUSA/). Tree City USA is a community improvement program sponsored by The National Arbor Day Foundation in cooperation with the US Conference of Mayors, the National League of Cities, the National Association of State Foresters, the USDA Forest Service and the SC Forestry Commission. In order to qualify, a community must meet four standards:
Establish a tree commission or designate a municipal department responsible for public trees
Develop, pass and implement a municipal public tree care ordinance
Conduct a local Arbor Day observance and celebration
Spend two dollars per capita on community forest management
These standards provide a framework for action and initial direction for a community forestry program.
Like the first rungs on a ladder, the standards help get a community started toward annual, systematic management of its tree resources. South Carolina’s Tree Cities have been steadily increasing over the past 12 years and in 2009 we recertified 42 entities. These include 38 municipalities, 3 military bases and 1 county.
In providing assistance to local units of government, the Community Forestry staff has developed relationships in many communities across the state. These include personnel in the following departments: planning and zoning, public works, parks and recreation, and city leadership. In addition, Community Forestry staff contacts with other agencies (SCDOT, SCDNR and NRCS), professional organizations (SC Chapter of the American Planners Association, SC Nursery and Landscape Association, SC Landscape and Turfgrass Association and the Municipal Association of SC), and non-profits (Trees SC, tree boards, and beautification boards) promotes relationship-building with these organizations.
All of these factors help to connect the public with trees, forests and the agency in general. It is through these connections that staff help bridge the gap when local government struggles with wildland-urban interface issues during expansion of population and jurisdictional boundaries.
Human Benefits of Trees and Forests
Trees and forests have a real impact on the economic, social, and physical well-being of people.
Folks gravitate toward green and well-landscaped areas where trees are the predominant feature. Trees planted in public places (streets, parks, schools, cemeteries, and college campuses, for example) as well as in accessible forested areas provide a wide array of tangible and non-tangible benefits to the public. Trees are on the job 24 hours every day working for all of us to improve our environment and quality of life.
Trees are major capital assets in cities and towns. Just as streets, sidewalks, sewers, public buildings and recreational facilities are a part of a community’s infrastructure, so are publicly owned trees. Trees, and collectively, community forests are important assets that require care and maintenance the same as other public property. (USFS 2003)
The community forest is seen by many municipal governments and business owners as improving the company’s image by sending a “message of care” to potential customers. Trees attract businesses and tourists to an area, thereby enhancing the community’s economic stability (GFC 2010). Some economic benefits of community forests include:
- More income for businesses. Customers will pay as much as 10 percent more for some goods and services provided by businesses that are located on tree-lined streets.
- Surveys show a 30 percent higher sales rate for shopping areas with large numbers of shade trees versus sales of the same products in shopping areas without trees.
- Customers tend to linger longer in areas with trees than those that are barren.
- “Trees absorb and store an annual average of 13 pounds of carbon each year. Community trees across the United States store 6.5 million tons of carbon per year, resulting in a savings of $22 billion in control costs” (GFC 2010).
- Employees who have a view of trees are more productive, with 23 percent less incidence of illness than those who cannot see trees. Those with a view also report a higher level of enthusiasm for their job and are generally more patient than those without a view (Wolf 1998).
The presence of trees also has a positive effect on occupancy rates and residential home sales.
- Neighborhood green spaces or greenways typically increase the value of properties located nearby.
- Healthy trees can add up to 15 percent to residential property value.
- Wooded apartment complexes provide preferred aesthetics that can increase occupancy rates (SCFC 2010).
- Trees can help cool the "heat island" effect in our inner cities and downtown areas. These islands result from storage of thermal energy in concrete, steel and asphalt. Heat islands are 3 to 10 degrees warmer than the surrounding countryside. The collective effect of a large area of transpiring trees (evaporating water) reduces the air temperature in these areas.
- Strategically placed shade trees - a minimum of three large trees around a home - can reduce air conditioning costs up to 30 percent. Shade trees offer their best benefits when deciduous trees are planted to shade all hard surfaces such as driveways, patios and sidewalks to minimize landscape heat load. (USFS 2003)
- Trees and other plants release oxygen (02) for us to breathe and in turn, absorb carbon dioxide (CO2 ) and other dangerous gases.
- Trees help to settle out, trap and hold particulate pollutants (dust, ash, pollen and smoke) that can damage human lungs.
- An acre of trees produce enough oxygen for 18 people every day.
- During one year, an acre of trees absorb enough CO2 to equal the amount produced when a car is driven 26,000 miles.
- Trees remove gaseous pollutants by absorbing them through the pores in the leaf surface. (USFS 2003)
Tree roots increase soil permeability, resulting in:
- Reduced surface runoff of water from storms.
- Reduced soil erosion and sedimentation of streams.
- Increased ground water recharge.
- Lesser amounts of chemicals transported to streams. (USFS 2003)
- Physical Activity/Obesity: Studies have found a correlation between community forests and the average amount of physical activity exerted by neighborhood residents. People are more inclined to get outdoors and exercise when their surroundings are greener. Greater physical activity can lead to fewer cases of obesity, which in turn may help reduce other health problems such as heart disease and diabetes. Savings to individuals and the nation can be substantial: health care costs in America associated with obesity top $100 billion a year.
- Asthma: Trees filter airborne pollutants and can reduce the conditions that cause asthma and other respiratory problems. Asthma incidents increase in urban communities where trees are eliminated in favor of new roads, homes, or commercial developments. The American Lung Association estimates that ozone-associated health care costs Americans about $50 billion annually (ALA 1997).
- Hospital Stays: Post-operative stays are shortened when patients have a view of trees and open spaces.
- Attention/Focus: Children who spend more time outside pay better attention inside. Attention-deficit/hyperactivity disorder (ADHD) children, in particular, are better able to concentrate, complete tasks, and follow directions after playing in natural settings.
- Reduced Air Temperatures: By reducing air temperatures and building energy use, and directly removing ozone and NOx from the air, trees reduce ozone concentrations. However, trees can also influence volatile organic compound (VOC) emissions that can lead to ozone formation.
- Reduced Ultraviolet Radiation: trees provide shade and therefore protection from the sun. Tree canopy coverage on school grounds and where people gather to shop and recreate can help decrease the chance of skin cancer formation.
Studies have identified a direct correlation between the amount of trees and grass in community common spaces and the use of those common spaces by residents, which leads to more opportunities for informal social interaction and greater relationships between neighbors.
- Trees make communities livable for people and soften the outline of masonry, metal and glass.
- Trees can be associated with specific places, such as memories of past events or times, or a favorite tree climbed as a youth.
- Less violence occurs in urban public housing where there are trees. Researchers suggest that trees afford a place for neighbors to meet and get to know each other (Kuo and Sullivan 2001). Their research showed that friendships developed into a network of support.
Because these benefits are so broad and all-encompassing, no specific data or research has been collected or conducted here in South Carolina. However, various data on the above quantifiers can be gleaned from numerous sources.
South Carolina is fortunate to have an abundance of forested land despite population growth over the past 20 years. This growth has been accompanied by urban/suburban sprawl primarily in regional pockets of growth in the Greenville-Spartanburg corridor, the Midlands, and areas along the coast. While continued population growth and land development fragments forest land it also offers opportunities to promote state-wide tree planting initiatives and interaction as well as the importance and value of trees and forests to non-traditional audiences such as those in energy production, health care, economic development and citizen groups.
Perhaps the biggest threat that links all of these factors is the potential loss of political support, cost-share grants and staffing to provide technical, educational and financial assistance to the entities that have a major role in benefiting most from the environmental services that trees and forests provide.
Over 75 percent of the U.S. population lives in cities (Nowak et al. 2000). As a result, more and more people are disconnected from natural resources such as forests that support them and the watersheds in which they live. As a result, urban residents may take for granted the important benefits provided by forests and trees in their own back yards.
Urban watershed forestry represents an important management approach given the many benefits provided by urban forests and the impact of development on forest structure and function and watershed health. Managing urban forests in ways that explicitly address watershed health can mitigate some of the negative impacts of forest fragmentation, soil compaction, and increased impervious cover in urban watersheds.
A partial listing of the watershed benefits of urban forests and the unique properties of the urban planting environment are as follows:
- Reducing construction and maintenance costs (by decreasing costs related to clearing, grading, paving, mowing and storm water management);
- Reducing stormwater runoff and flooding;
- Reducing urban heat island effect1;
- Enhancing function of stormwater treatment;
- Improving soil and water quality;
- Reducing stream channel erosion;
- Providing habitat for native plants, terrestrial and aquatic wildlife; and
- Preserving of native ecotypes.
Population growth, residential and industrial development, and the resulting demands on our landscape and waterways have led to water quality and quantity concerns throughout South Carolina. Currently, more than 1,150 of our lakes, rivers and creeks have been listed as impaired by the state’s Department of Health and Environmental Control (DHEC).Impervious surfaces such as roads, roofs, driveways, streets, and parking lots increase not only stormwater volume, but also the rate of flow. The volume of runoff in an urban area is five times greater than that of an equally large forested area. The consequences of stormwater runoff in populated places are flooding, soil erosion, and non-point source contaminants, which negatively impact both the built and natural environment. Impacts to the built environment include property damage and loss and poor quality drinking water. Impacts to the natural environment include waterway sedimentation and poor water quality for aquatic life.
In accordance with recently passed federal legislation, South Carolina adopted a permitting process designed to manage stormwater. The stormwater rules require all construction sites of one acre or more, many industrial sites, and all regulated Municipal Separate Storm Sewer Systems (MS4s) to obtain a permit. Currently, there are over 70 municipalities throughout the state that are required to comply with the MS4 regulations. In addition, EPA stormwater rules require many of South Carolina’s cities and towns to implement public outreach and education programs as part of their local efforts to reduce pollutants in stormwater runoff.
The main influence of urban watershed problems, and hence, stormwater management is land conversion of greenspace to grayspace. Examples of this land use change are the conversion of forests (greenspace) to streets (grayspace) and fields to parking lots. As with many environmental issues, stormwater management is not confined to jurisdictional boundaries.
Natural resources professionals know the many benefits and values of trees and forests. These experts must be more proactive in reaching those outside of the field who can benefit from this knowledge.
Although the Forestry Commission does not have any control over the pace of population growth or development, the agency can influence how communities of people and structures are arranged and built. This can be accomplished through affecting local planning and zoning policy, educational awareness, and technical assistance.
Literature Cited and References
Saure, Amanda. 2002. The Value of Conservation Easements: The Importance of Protecting Nature and Open Space Discussion Paper. World Resources Institute. Available online at http://www.landscope.org/rhythmyx/action/conserve/easements/item20493.pdf
American Lung Association (ALA). 1997. Childhood Asthma: A Matter of Control. Pamphlet.
Nowack, David J.. 2005. Strategic tree planting as an EPA encouraged pollutant reduction strategy: how urban trees can obtain credit in state implementation plans. USDA Forest Service Northeastern Research Station. Sylvan Communities. Pages 24 – 27.
Kuo, Frances E. and William C. Sullivan. 2002. Human-Environment Research Laboratory at University of Illinois at Urbana Champaign bulletin series Vol. 1 No.1 Girls and Greenery. Available online at http://lhhl.illinois.edu/girls_self-discipline.htm
Cappiella, K., T. Wright, and T. Schueler. 2005. Urban Watershed Forestry Manual Part 1: Methods for Increasing Forest Cover in a Watershed. Center for Watershed Protection. Available online at www.cwp.org
Giacalone, Katie. 2008. Carolina Clear Rain Garden Manual. Clemson University PSA. Available online at http://www.clemson.edu/public/carolinaclear
Kuo, Frances E. and William C. Sullivan. 2001. Environment and crime in the inner city: Does vegetation reduce crime? Environment and Behavior 33(3): 343-367.
Kuo, Frances E. and William C. Sullivan. 2001. Human-Environment Research Laboratory at University of Illinois at Urbana Champaign bulletin series: Vol.1 No.3 Go Out and Play, Vol. 1 No. 2 Green Streets, Not Mean Streets, Vol. 1 No. 5 Green Relief and Vol.1 No. 6 Cooler in the Shade. Available online at http://lhhl.illinois.edu/coping.htm
Georgia Forestry Commission (GFC). 2010. Environmental benefits of urban trees. Available online at http://www.gfc.state.ga.us/CommunityForests/TreeBenefits.cfm
Mulkey Engineers & Consultants. 2008. Sumter City-County Watershed Study and Report. Sumter City-County Planning Department.
The National Arbor Day Foundation. 2010. Tree City USA: Greening America. Brochure. Available online at www.arborday.org
USDA Forest Service Southern Region. 2003. Benefits of Urban Trees. Forestry Report R8-FR 17. Available online at www.urbanforestrysouth.org
USDA Forest Service. 2005. Strategic tree planting as an epa encouraged pollutant reduction strategy: How urban trees can obtain credit in state implementation plans. Northeastern Research Station. 5 pp. Available online at http://www.fs.fed.us/ne/newtown_square/publications/other_publishers/ne_2005_nowak003p.pdf
USDA Forest Service. 2006. Performance-Based Methodology for Allocating Urban & Community Forestry Program Funds. Appendix: Definitions and Examples.
Wolf, Kathy. 1998. Urban benefits: psycho-social dimensions of people and plants. University of Washington, College of Forest Resources. Fact Sheet #1. 2 pp.
1urban heat island effect - an area, such as a city or industrial site, having consistently higher temperatures than surrounding areas because of a greater retention of heat, as by buildings, concrete, and asphalt. (source: http://www.answers.com/topic/urban-heat-island)
For Priority Area Maps, see Appendix 2.