One of the major benefits of planting trees is the accomplished feeling of doing something good for the environment. And with 127 million Americans alone affected by air pollution, we need solutions. We see countless campaigns dedicated to planting trees in areas that have been deforested, and we even celebrate Arbor Day each year — a holiday solely dedicated to publicly planting trees in countries across the world. (By the way, the Arbor Day Foundation does some great work — check them out here!) But how exactly does planting trees help reduce air pollution — and which trees are best for the job?
You probably already know that trees work in the environment similarly to how lungs work in the body — trees release oxygen and pull in carbon dioxide. Removing carbon dioxide from the air is so important because “CO2 is one of the major contributing elements to the greenhouse effect. Trees trap CO2 from the atmosphere and make carbohydrates that are used for plant growth. They give us oxygen in return. According to ColoradoTree.org, about 800 million tons of carbon are stored in the trees that make up the urban forests of the U.S. This translates to a savings of $22 billion in control costs. Mature trees can absorb roughly 48 pounds of CO2 a year. The tree in turn releases enough oxygen to sustain two human beings. (Source)”
Planting trees also helps to reduce ozone levels in urban areas, thanks to the shade they provide and thus cooler temperatures. “Reduced air temperatures by trees and parks can not only lead to reduced emission of air pollutants from numerous sources (e.g. cars, power plants), it can also lead to reduced formation of ozone as ozone formation tends to increase with increasing air temperatures. (Source)”
Curious about the scientific process that occurs in order for the physical action of air cleaning to happen when planting trees? Although the answer is slightly complex, we like this concise definition from BBC Science Focus: Particulate matter suspended in polluted air tends to settle onto leaves, and certain gases including nitrous dioxide (NO2) are absorbed by leaves’ stomata, filtering the air and reducing pollution levels slightly.
If planting trees to improve the environment is important to you, here are a few that we recommend:
Bald Cypress: Native to swampy settings, you can find this Cypressalong slow-moving creeks, streams and rivers. A key feature of these trees is their “knees”, knobby segments of the roots which protrude above the water to provide oxygen and stability to the tree in these environments. The Bald Cypress is also able to tolerate dry, sunny weather however and can be ornamental in a variety of landscapes. Their soft, feather-like foliage is bright green and their shaggy bark is a greyish brown. A deciduous conifer, their foliage will become cinnamon and fiery orange in the fall and eventually shed, thus giving these trees their name.
Willow Oak: The beautiful Willow oak tree is easy to grow and a wonderful addition to any landscape! This deciduous tree has a willow-like, slender, glossygreen leaves and fast growth rate. A member of the red oak group, it will grow anywhere from 40 to 75 feet tall in maturity. Yellowish green flowers will bloom beginning in April as its leaves begin to appear.