The Value of Urban Trees
Many people view trees as symbolic, representing human traits we are taught to admire (such as wisdom and steadfastness, even in the face of adversity) The sheltering nature of trees suggests parental care, and many people equate their heritage with the deep roots of a tree. But urban trees also serve a number of more practical purposes.
Research shows that trees help reduce stress in the workplace and encourage recovery for hospital patients. The presence of community trees is linked to higher property values (as much as 27 percent), increased tax revenues, increased income levels, faster real estate sales (turnover rates), increased number of jobs and worker productivity, and increased numbers of customers or shoppers.
Because of many variables, determining the economic value of a community tree can be challenging. According to the Minnesota Department of Natural Resources, research has shown that trees can provide up to $7 in benefits each year for every $1 invested in caring for them. Benefits include increased property values, pollution control, and energy savings. While individual trees have value, the variability of species, size, condition, and function makes it even more difficult to determine their economic value. Aesthetics aside, trees provide many economic benefits, both direct and indirect.
Some Direct Benefits
Direct economic benefits are usually associated with energy costs. For example, tree shade can reduce air conditioning costs in residential and commercial buildings by 30 percent. Windbreaks can shield homes against wind and snow, reducing heating costs by 20 to 50 percent. In city areas without tree cover, streets and parking lots can raise air temperatures as much as 35 degrees. Such "heat islands" can cause cities to be 5 to 9 degrees warmer than surrounding areas. However, a mature tree can reduce high summer temperatures by 2 to 9 degrees F. Because of this, formulas are used to estimate monetary values of large trees for landscape and replacement costs. Some legacy trees in the southeastern United States have been valued up to $100,000.
Some Indirect Benefits
The indirect economic benefits of trees are even greater. On average, an acre of trees can store 2.6 tons of carbon annually and generate enough oxygen daily for 18 people. As more and more statistics are generated to show how community trees store carbon and clean the atmosphere, models show that in 50 years, one tree can generate $30,000 in oxygen, recycle $35,000 of water, and remove $60,000 of air pollution.
Community tree canopies also intercept, slow, evaporate, and store water through normal tree functions. Studies show that for every 5 percent of tree cover area added to a community, stormwater run-off is reduced by approximately 2 percent. As tree canopy increases, so does air quality. Meanwhile, there is a decrease in energy costs and stormwater runoff.
The facts and statistics are numerous when it comes to the benefit of community trees. The benefits go well beyond economics to include sound or noise reduction, visual screening, wind control, water quality, glare reduction, wildlife habitats, and, of course, aesthetic quality. The important thing to remember is beauty isn't everything.
Six Things Trees Do for You Every Day
Improve Air Quality
- Tree leaves absorb carbon dioxide and poisonous atmospheric gases and produce oxygen for breathing.
- American Forests reports that in one year, a mature tree absorbs 48 pounds of carbon dioxide produced. Two mature trees produce enough oxygen for a person to breathe during a year.
Improve Water Quality
- Trees reduce the impact of rain, which results in less soil erosion and runoff into our storm sewers.
- Golden Valley's wooded areas help prevent the transport of sediment and chemicals into creeks and wetland areas.
Save Energy & Money
- Properly placed trees can reduce air conditioning needs by 30% and heating cost by 20 to 50%. (USDA)
- Trees placed properly for windbreak protection can cut the energy used for heating up to 30%.
Increase Economic Stability
- USDA studies indicate that healthy mature trees can increase property value by an average of10 to 20%. The National Arbor Day Foundation reports that people spend more time shopping along tree-lined streets.
- Apartments and offices in wooded areas tend to rent quicker and have longer leases than treeless locations.
Reduce Noise Pollution
- A USDA report states that trees help to absorb loud sounds from vehicles and other sources.
- Each 100-foot width of trees can absorb about six to eight decibels of sound intensity. This is beneficial to residents along busy highways, which can generate noise levels as high as 72 decibels
Create Wildlife Diversity
- Trees provide a suitable habitat for animals and birds that wouldn't survive in Golden Valley without them.