Tree Facts

What Can We Learn About Trees?

Trees are among the largest, yet subtlest, beings on earth. Remarkably, trees manage to care for everything that lives: By enriching the earth's soil and preventing erosion, trees allow food and wetlands to thrive. By producing oxygen and removing carbon dioxide, trees allow humans and animals to survive. By providing homes for creatures big and small, living beings enjoy shelter. By shading our neighborhoods, trees keep outdoor temperatures comfortable. By withstanding storms, trees provide protection and hope. By providing relief when the sun scorches, trees protect fragile human skin. By metamorphosing seasonally and annually, trees remind us that growth need never stop, and that life is filled with surprises.

There is much, much more! Yet trees don't spend much time tooting their own horns. Because of their modesty (which is perhaps due to the fact that they don't have mouths), the unique value of trees is frequently overlooked and underestimated. How ironic, then, that there is hardly a being on earth that does so much for so many beneficiaries than a tree. Read on to learn how this unsung hero regularly makes our lives better...

Wildlife

Living trees provide homes, protection, and food to many forms of wildlife.

Dead and decaying trees on the ground replenish soils by returning important nutrients and fortifying new generations of plants.

Almost all woodpeckers can dig out holes for nests only in standing dead trees or the dead stubs on live trees, and many other wildlife species depend on dead wood for nesting.

Air Pollution

Trees help humans and animals breathe by producing oxygen, and removing carbon dioxide from the air. Carbon dioxide, produced from burning fossil fuels, is the greenhouse gas most blamed for trapping heat in earth's atmosphere, and is linked to global climate change. Trees use carbon dioxide to make their food.

In 24 hours, one acre of trees produces enough oxygen for 18 people and absorbs as much carbon dioxide as a car produces in 2 years of operation.

Tree leaves help trap and remove tiny particles of soot and dust which otherwise damage human lungs.

Water & Soil Pollution

The number one source of water pollution in metro Atlanta is excessive storm runoff. Trees act like sponges and filters -- slowing, cleaning, and absorbing runoff water.

Without the root networks of trees, stormwater surges into creeks, lakes, and rivers, carrying the poisons and pollutants that have already left 55 miles of creeks in metro Atlanta "unfit for swimming and fishing." Two dozen native fish species have already disappeared. The Chattahoochee River itself is in peril.

Trees prevent erosion by trapping soil that would otherwise become silt. Silt destroys fish eggs and other aquatic wildlife, and makes rivers and streams shallower, causing more frequent and more severe flooding. Trees along streams also hold stream banks in place to protect against flooding.

Visual Pollution

Highway and street trees provide a scenic buffer and lessen the impact of car and truck emissions by collecting harmful air particles while releasing needed oxygen.

Traffic Calming

A continuous tree canopy typically causes a 5-10 mph decrease in speed. Trees also save asphalt by blocking the direct sunlight that destroys it.

Noise Pollution

Trees reduce invisible pollution like noise pollution as well. Groves of trees play a vital role in noise abetment, so plant trees en masse so that leaves can reduce the sounds of traffic and urban living.

Temperature

By creating shade, trees moderate temperatures both globally and in the micro-climates of cities and counties.

Tree Canopy

The "State of Our Urban Forests" study recommended that healthy cities aim for a 40% tree cover (equivalent of 20 large trees per acre) to ensure their ecological, economic, and social sustainability.

Atlanta has an average tree cover of just 27%. Boston's tree cover is 21 %, Austin 34%, Baltimore 31%, Milwaukee 18%, Chicago 11%, and New York City has 16 percent.

Sixty percent of Atlanta's natural tree cover has been removed over the last 20 years.

To meet state sewer standards, the City of Atlanta is spending $240 million to counter effects associated with the loss of tree canopy.

In the Chamblee area, the loss of 44% of its tree cover has resulted in storm water runoff problems costing $129 million.

"Heat Islands"

Tree loss in Atlanta and neighboring counties has resulted in urban "heat islands" with temperatures 3-10 degrees above the surrounding countryside. The hot weather dome over the Atlanta area has changed local weather patterns by reducing rain in some areas and increasing the intensity of thunderstorms in others.

"Heat islands" also exponentially increase air pollutants. When pollutant chemicals are superheated by high air temperatures, they become more volatile and interact with each other to create ground level ozone which would not happen at lower temperatures. That is why Atlanta's most dangerous levels of air pollution occur in the summer.

Medical Value

Trees provide substances with medicinal value such as the active ingredients used in asthma medications and cough remedies. Aspirin is derived from the bark of a willow tree.

Hospital patients recover more quickly and with fewer drugs, prisoners suffer less health problems, and stress for all beings is reduced when trees are in view.

Trees provide green scenery shown to speed up patient recovery in hospitals and reduce stress.

Home

Planting 30 trees each year offsets greenhouse gases from your car and home.

Three trees located strategically around your house can cut air conditioning bills in half. On a larger scale, the cooling effects of trees can save millions of energy dollars.

Property values of homes with trees in the landscape are 5 - 20% higher than equivalent properties without trees.

In addition to creating a sense of privacy in urban environments, the presence of trees in urban neighborhoods has been linked to less crime.

A pleasant yard with good-sized trees can boost your property values by up to 20%. Trees growing around a house can cut air conditioning costs by half and heating bills by $50 a year.