Urban Forestry

Benefits of Urban Trees

Urban Benefits - Trees

Urban and Community Forestry: Improving Our Quality of Life

Urban and community forestry can make a difference in our lives. Each one of us can make a personal contribution. As we develop and apply technologies for a better way of life, often times side effects adversely affect our natural environment. For example, in our urban areas summer temperatures and noise levels are higher than in the surrounding countryside. Air pollution problems are more concentrated, and the landscape is significantly altered, reducing personal health benefits available to us by having access to wooded areas and green open spaces. Trees help solve these problems. Now, 75 per-cent of us live in cities and towns and we can act individually to improve our natural environment through the planting and care of trees on our own streets, and by supporting community-wide forestry programs. Through technology we are learning more about trees and how they benefit mankind, and how we can do a better job of planting and caring for these trees that make up our urban forests.

Urban Benefits-Sidewalks

TREES ADD BEAUTY AND IMPROVE PERSONAL HEALTH

Trees are major capital assets in America’s 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, the urban forest-are important assets that require care and maintenance the same as other public property.

Trees are on the job 24 hours every day working for all of us to improve our environment and quality of life.

Without trees, the city is a sterile landscape of concrete, brick, steel and asphalt. Picture your town without trees. Would it be a place where you would like to live? Trees make communities livable for people. Trees add beauty and create an environment beneficial to our mental health. Trees:

Trees impact deeply on our moods and emotions, providing psychological benefits impossible to measure. A healthy forest growing in places where people live and work is an essential element of the health of the people themselves. Trees:

A well-managed urban forest contributes to a sense of community pride and ownership.

Urban Benefits - Without TreesUrban Benefits - With TreesUrban Benefits - Trees

TREES REDUCE AIR POLLUTION

Trees and other plants make their own food from carbon dioxide (CO2) in the atmosphere, water, sunlight and a small amount of soil elements. In the process, they release oxygen (02) for us to breathe. Trees:

Trees remove gaseous pollutants by absorbing them through the pores in the leaf surface. Particulates are trapped and filtered by leaves, stems and twigs, and washed to the ground by rainfall.

Air pollutants injure trees by damaging their foliage and impairing the process of photosynthesis (food making). They also weaken trees making them more susceptible to other health problems such as insects and diseases.

The loss of trees in our urban areas not only intensifies the urban "heat-island" effect from loss of shade and evaporation, but we lose a principal absorber of carbon dioxide and trapper of other air pollutants as well.

Carbon Dioxide and other gasesThe burning of fossil fuels for energy and large scale forest fires such as in the tropics are major contributors o the buildup of CO2 in the atmosphere.
Managing and protecting forests and planting new trees reduces CO2 levels by storing carbon in their roots and trunk and releasing oxygen into the atmosphere.
Some of the major air pollutants and their primary sources are:
POLLUTANTMAJOR SOURCES
Carbon dioxideBurning oil, coal, natural gas for energy.
Decay and burning of tropical forests
Sulfur dioxideBurning coal to generate electricity.
Hydrogen fluoride
and silicon tetrafluoride
Aluminum and phosphate fertilizer production, oil refineries, and steel manufacturing.
OzoneChemical reactions of sunlight on automobile exhaust gases. Ozone is a major pollutant in smog.
MethaneBurning fossil fuels, livestock waste, landfills and rice production.
Nitrous oxidesBurning fossil fuels and automobile exhausts.
ChlorofluorocarbonsAir conditioners, refrigerators, industrial foam.
TREES FIGHT THE ATMOSPHERIC GREENHOUSE EFFECT
Heat trapping gases Heat from Earth is trapped in the atmosphere due to high levels of CO2 and other heat-trapping gases which prohibit it from releasing heat into space-creating a phenomenon known as the "greenhouse effect".

The greenhouse effect is created when heat from the sun enters the atmosphere and is prevented from radiating back into space by air-polluting gases. The buildup of about 40 heat-trapping gases is created mostly by human activities. Heat buildup threatens to raise global temperatures to levels unprecedented in human history. About half of the greenhouse effect is caused by CO2.

Tree roots hold soil in place

Trees act as a carbon sink by removing the carbon from CO2 and storing it as cellulose in the trunk while releasing the oxygen back into the air. A healthy tree stores about 13 pounds of carbon annually - or 2.6 tons per acre each year.

Trees also reduce the green-house effect by shading our homes and office buildings. This reduces air conditioning needs up to 30 percent, thereby reducing the amount of fossil fuels burned to produce electricity.

This combination of CO2 removal from the atmosphere, carbon storage in wood, and the cooling effect makes trees a very efficient tool in fighting the greenhouse effect.

TREES CONSERVE WATER AND REDUCE SOIL EROSION

Trees create organic matter on the soil surface from their leaf litter. Their roots increase soil permeability. This results in:

Without trees, cities would need to increase sewage and storm water drainage channels and .waste - treatment capacities to handle increased water runoff.

TREES SAVE ENERGY

Strategically placed trees can be as effective as other energy saving home improvements, such as insulation and the installation of weather-tight windows and doors. Trees can help reduce your heating and cooling costs.

Trees save energy through cooling in the hotter months. They provide a windbreak during winter. This results in burning less fossil fuels to generate electricity for cooling and heating.

Shade

Strategically placed shade trees-a minimum of three large trees around your home-can reduce air conditioning costs up to 30 percent. Shade trees offer their best benefits when you:

Use evergreens, which retain their leaves/needles year-long, in a planned pattern. They will serve as windbreaks to save from 10 to 50 percent in energy used for heating. Evergreens offer their best benefits when you:

Get professional assistance to assure correct selection of species and their placement to maximize energy savings.

Without Trees Hotter
More Glare
More Noise
More Water Runoff
More Energy Used
Harsh Landscape
With Trees Cooler
Less Glare
Absorbs Noise
Less Runoff
Less Energy
More Beautiful

TREES MODIFY LOCAL CLIMATE

Trees can help cool the "heat island" effect in our inner cities. 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.

Trees also:

Urban Benefits

TREES INCREASE ECONOMIC STABILITY

The scope and condition of a community’s trees and, collectively, its urban forest, is usually the first impression a community projects to its visitors. Studies have shown that:

A community’s urban forest is an extension of its pride and community spirit.

TREES REDUCE NOISE POLLUTION

Trees absorb and block noise from the urban environment

TREES CREATE WILDLIFE AND PLANT DIVERSITY

Trees and associated plants create local ecosystems that provide habitat and food for birds and animals. They offer suitable mini-climates for other plants that would otherwise be absent from urban areas. Biodiversity is an important part of urban forestry.

Habitat for birds.Increase property value.

TREES INCREASE PROPERTY VALUES

We all know that property that is well landscaped with trees and other plants is more desirable than property sitting on a barren landscape. Studies have shown that:

Tree City USA.

HELPING TREES AND YOUR URBAN FOREST

URBAN AND COMMUNITY FORESTRY PROGRAMS

Trees on public property belong to all of us. Proper management of this valuable resource is known as urban and community forestry. How is the urban forest in your community being cared for?

For more information on urban and community forestry contact your nearest USDA Forest Service office or the SC Forestry Commission.

TREE CITY USA

One way you can get special recognition for urban forestry activities in your town is to apply for certification as a Tree City USA. Hundreds of cities and towns across the nation are achieving this status by meeting Tree City USA standards. Communities of any size can qualify, from less than one hundred to millions of people.

Write to the National Arbor Day Foundation, 100 Arbor Avenue, Nebraska City, NE 68410 or your State Forester for details on the Tree City USA program.

"Never doubt that a small group of thoughtful,
committed citizens can change the world. Indeed,
it’s the only thing that ever has."

- Margaret Mead

FOR ADDITIONAL INFORMATION

Contact the office listed below:

Sources of Assistance

USDA Forest ServiceUS Forest Service
1720 Peachtree Road, NW
Atlanta, GA 30367-9102

SC Forestry Commission

Clemson Extension Service

USDA Forest Service - Southern Region
Southern Group of State Foresters
Cooperative Extension Service

Forestry Report R8-FR 17
April 1990

Reproduced by permission from the USDA Forest Service


Urban Forestry