Marketability and Community Economic
Well-being
Trees enhance property values. Public agencies and real estate professionals estimate that trees in neighborhoods can enhance property values by 7 to 20 percent. They can provide communities with a sense of identity. The streets of Sequoyah Hills, Island Home, North Hills and Fairmont Boulevard are good local examples. Properties in these neighborhoods are viewed favorably in the market. Cities with abundantly wooded landscapes tend to sell themselves as places that attract new businesses and residents. Asheville, Charlotte, Minneapolis, Portland and Seattle are examples of such cities.

Psychological and Physical Health
Trees provide beauty and a sense of place. Surveys have shown that almost 90 percent of Americans consider the beauty of trees to be very important. The presence of trees has been shown to have therapeutic value for patients recovering from surgery. Trees also block noise. While not as effective as sound barriers, the US Department of Transportation has found that continuous rows of trees can mask highway noise by damping the sound through the rustle of the leaves. Many citizens, especially an aging population that enjoys walking as a basic form of exercise, gravitate to places where shade trees and wildlife habitat enhance their experience.

Energy Conservation and Air Quality
Trees provide an evaporative cooling effect, lowering temperatures in cities. Areas with trees are typically 5 to 9 degrees Fahrenheit cooler than conventional strip commercial or downtown development. By lowering extreme temperatures they reduce the physical stress that people suffer in high heat. The savings in air conditioning costs can also be significant. The Environmental Protection Agency and the US Forest Service have shown that well-placed trees can reduce the costs associated with summer cooling by 10 to 50 percent. Trees store carbon, offsetting the byproducts of burning fossil fuels. Consequently, carbon dioxide is absorbed by trees directly. A mature tree extracts more than 25 pounds of carbon from the air per year, transforming it to wood and leafy material and releasing oxygen in the process. Additionally, trees capture airborne particulate pollution, removing dust and chemicals from the atmosphere.

Stormwater Control and Water Quality
Trees intercept stormwater and reduce runoff and soil erosion. When rail falls, the drops are deflected by leaves, lessening the impact of the storm on underlying soils. Ground cover and roots hold the soils in place, also reducing tendencies toward erosion. The stormwater runoff rates from forested areas are the least of any landscape, helping to reduce flooding and serving as a filter of pollutants.

Citizen Participation
MPC, with the assistance of the League of Women Voters of Knoxville/Knox County, held six public workshops in May and June 2002 to allow citizens to talk about street tree issues and express preferences about tree planting. At the workshops citizens responded to a visual preference survey of various streetscapes. These included photographs of neighborhood streets, commercial corridors, urban streets and sidewalks and parking areas. Respondents were told to take a number of issues into account such as aesthetics, pedestrian and automobile safety and environmental considerations. In addition to choosing a preference, respondents also noted what appealed to them about their choice (for instance, the location and species of trees, the lack of utilities and the location of sidewalks). An example of the visual preference survey is shown on the following page.

Citizens also participated in group discussions offering ideas about several significant topics, including:

• Areas where trees should be conserved
• Species that should be planted and in what types of places
• Species that should be avoided
• Road corridors and neighborhoods where trees are needed most

The visual preference survey was placed on the MPC website where citizens could respond by e-mail. Approximately 100 Knoxvillians participated in the workshop and website processes.

From the workshops, various citizens volunteered to work with MPC staff to identify street tree planting opportunities and concepts for sections of the community. Their ideas are reflected in the Knoxville Street Tree Master Plan. The citizen-based Knoxville Tree Board and its planning and design committee were also involved in the review and concepts for plan development. Public meetings were held in October 2002 to review the draft with citizens. The draft plan was also placed on MPC’s website for public review.