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 Urban Shade Trees

Urban Shade Trees 

By planting trees and shrubs, we return to a more natural, and less artificial environment. Birds and other wildlife are attracted to the area. The natural cycles of plant growth, reproduction and decomposition are again present, both above and below ground. Natural harmony is restored to the urban environment.

Trees have both environmental and economic benefits:


Reduce stormwater runoff and erosion

Trees intercept water, store some of it, reduce storm run-off and the possibility of flooding.

Tree roots hold soil in place so it cannot easily be washed away by wind or water; the decaying of dead tree parts returns nutrients to the soil.  The root systems of trees hold in place soil that, if washed away by heavy rains, would flow into streams and rivers, making them shallower and allowing flood waters to overflow protective banks.

�The planting of trees means improved water quality, resulting in less runoff and erosion. This allows more recharging of the ground water supply. Wooded areas help prevent the transport of sediment and chemicals into streams." 

-  USDA Forest Service 

Energy Conservation

Trees have been called the "low tech" solution to energy conservation. Shade from trees reduces the need for air conditioning in summer. In winter, trees break the force of winter winds, lowering heating costs.  Studies have shown that parts of cities without cooling shade from trees can literally be "heat islands," with temperatures as much as 12 degrees Fahrenheit higher than surrounding areas. By using trees in the cities, we are able to moderate the heat island effect caused by pavement and buildings in commercial areas.

"The net cooling effect of a young, healthy tree is equivalent to ten room-size air conditioners operating 20 hours a day."

 - U.S. Department of Agriculture

"Trees properly placed around buildings can reduce air conditioning needs by 30 percent and can save 20 - 50 percent in energy used for heating." 

-  USDA Forest Service

Climate Control

An average tree stores 13 pounds of carbon every year and a community forest can absorb enough carbon dioxide annually to compensate for driving a car 26,000 miles. Keeping the earth's carbon levels in balance is critical; carbon build-up in the atmosphere is a major contributor to global warming.  The burning of gasoline and other fossil fuels has added more carbon dioxide to the atmosphere than trees and the oceans can absorb. That is the principal cause of global warming. The more trees there are, the more carbon dioxide is absorbed, and the less global warming we have.

"One acre of forest absorbs six tons of carbon dioxide and puts out four tons of oxygen. This is enough to meet the annual needs of 18 people." 

-  U.S. Department of Agriculture

"There are about 60-to 200- million spaces along our city streets where trees could be planted. This translates to the potential to absorb 33 million more tons of CO2 every year, and saving $4 billion in energy costs." 

-  National Wildlife Federation 

Improve water and air quality

Tree leaves and roots act as natural filters of air and water (rain and ground), removing particulate matter and polluting nutrients.  The hair-like root fibers of trees help filter ground water, trapping nutrients and pollutants that could contaminate it.

Air quality can be improved through the use of trees, shrubs and turf. Leaves filter the air we breathe by removing dust and other particulates. Rain washes the pollutants to the ground. Leaves absorb carbon dioxide from the air to form carbohydrates that are used in the plant's structure and function. In this process, leaves also absorb other air pollutants such as ozone, carbon monoxide, and sulfur dioxide, and give off oxygen.

Improve property values and attract economic growth

Trees increase in value from the time they are planted until they mature. Trees are a wise investment of funds since landscaped homes are more valuable than non-landscaped homes. The savings in energy costs and the increase in property value directly benefit each homeowner.



The indirect economic benefits of trees are even greater. These are available to the community or region. Lowered electricity bills are paid by customers when power companies are able to use less water in their cooling towers, build fewer new facilities to meet peak demands, use reduced amounts of fossil fuel in their furnaces and need fewer measures to control air pollution. Communities can also save if fewer facilities must be built to control storm water in the region. To the individual these savings are small, but to the community, reductions in these expenses are often in the thousands of dollars.

"Landscaping, especially with trees, can increase property values as much as 20 percent." 

- Management Information Services/ICMA

"Trees can be a stimulus to economic development, attracting new business and tourism. Commercial retail areas are more attractive to shoppers, apartments rent more quickly, tenants stay longer, and space in a wooded setting is more valuable to sell or rent." 

-  The National Arbor Day Foundation

 "Healthy, mature trees add an average of 10 percent to a property's value." 

- USDA Forest Service