Trees improve the quality of air we breath in several ways:

• Trees intercept particulate matter (PM₁₀) such as dust, ash, dirt, pollen, and smoke on the leaves, branches, and trunks of trees. These elements are later washed off and absorbed into the soil or flow to wastewater treatment facilities. Once removed from the air, most particulate pollutants are much less dangerous or completely innocuous.
• Trees absorb gaseous pollutants (such as ozone and nitrogen dioxide) through leaf surfaces and incorporate them into the tree.
• Trees reduce low altitude air temperatures, which decreases the production of ozone. This is done primarily by shading heat-absorbing roadways, especially asphalt. Trees also cool themselves and their surroundings through the process of transpiration, by which water from the roots is evaporated through leaves.
• Trees reduce surface temperatures, which reduces the need for air-conditioning. This means power plants don't have to work as hard, and the amount of pollutants emitted is less than there would be in the absence of trees.
• Trees are net releasers of oxygen, which is necessary for all animal life on the planet. Growing evidence suggests that as global carbon dioxide levels rise, global oxygen levels are falling even faster.

Findings

• Buckeye-Shaker Square's urban forest annually removes 1,362.90 ounces of carbon monoxide, 24,170.70 ounces of ozone, 5,790 ounces of nitrogen dioxide, 2,075.64 ounces of sulfur dioxide, and 1,723.70 ounces of fine particulate matter (PM_2.5). The total value of this pollution abatement amounts to approximately $10,278.93, or $3.87 per tree.
• Cudell's urban forest removes 977.90 ounces of carbon monoxide, 17,670.50 ounces of ozone, 4,262.50 ounces of nitrogen dioxide, 1,511.60 ounces of sulfur dioxide, and 1,315.80 ounces of fine particulate matter (PM_2.5). The total value of this pollution abatement amounts to approximately $7,534.92, or $4.78 per tree.

Pollutants Removed