News & Press
|Getting the Job Done - Ecological Benefits of Trees|
An energy efficient landscape is not only beautiful, but actively reduces our carbon footprint while benefiting the environment in other ways, as well as benefitting the homeowner and community. Trees in general provide ecological services that include 1) reduced air pollution, 2) stormwater mitigation, 3) carbon storage, 4) improved water quality, and 5) reduced energy consumption.
Trees reduce air pollution by trapping particulate matter in their leafy canopies and by absorbing noxious pollution into their leaves. These pollutants are either washed away with rain, or absorbed and incorporated into the soil. These actions reduce human health problems related to air pollution. Tree canopies also intercept large amounts of rain, reducing the amount of runoff that is discharged into streams and rivers and extending the time that a watershed has to absorb rainfall. This reduces flooding and erosion. As trees grow, they accumulate biomass that absorbs carbon and nutrients, locking them into a biological cycle that keeps them out of the atmosphere and hydrosphere and keeping them out of water resources. The storage of carbon reduces the greenhouse effect that is linked to problems of global climate change.
In summer, trees help cool the climate by transpiring water from their leaves. When groups of trees intercept sunlight and use it for photosynthesis, they shade roads, buildings, and other structures, and they help reduce energy consumption.
Here are just a few ways that trees specifically, and landscapes in general, provide benefits.
ü Properly selected, properly planted and maintained, healthy trees can reduce energy consumption
o Using trees in urban locations can help reduce the “heat island effect” by as much as 9° F.
o National Academy of Sciences (NAS) estimates that urban America has planting space for at least 100 million trees: an annual energy savings of 50 billion kilowatt-hours. This will save users $3.5 billion annually.
ü Increasing tree canopy in urban areas can reduce surface air temperature by 1-2° C, reducing energy demand and improving air quality.
ü A well-planned landscape can reduce an unshaded home’s summer air-conditioning costs by 15-50%
ü In winter, those homes with properly placed windbreaks averaged 25% less fuel consumption. This saves the homeowner between $100-250 in energy costs annually.
ü Healthy urban forests (including suburban and urban neighborhoods) have a positive effect on real estate prices. The total value is between $3.1 million and $19.2 million.
ü Over a 50-year lifetime, a tree generates $31,250 worth of oxygen, provides $62,000 worth of air pollution control, recycles $37,500 worth of water, and controls $31,250 worth of soil erosion.
ü Each person in the U.S. generates approximately 2.3 tons of CO2 each year. A healthy tree stores about 13 pounds of carbon annually -- or 2.6 tons per acre each year. An acre of trees absorbs enough CO2 over one year to equal the amount produced by driving a car 26,000 miles.
ü Trees reduce topsoil erosion, prevent harmful land pollutants contained in the soil from getting into our waterways, slow down water run-off, and ensure that our groundwater supplies are continually being replenished. For every 5% of tree cover added to a community, stormwater runoff is reduced by approximately 2%.