Trees are like the lungs of the planet. They breathe in carbon dioxide and breathe out oxygen. Additionally, they provide habitat for birds and other wildlife. But that's not all trees do for us! To see just how much trees are essential to the planet and to humans, let's look at the following statistics:
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 ColoradoTrees.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.
Trees also help to reduce ozone levels in urban areas. In New York City, a 10 percent increase in urban canopy translated to a reduction of peak ozone levels by around 4 parts per billion. (Source: Luley, Christopher J.; Nowak, David J. 2004. Help Clear the Smog with Your Urban Forest: What You and Your Urban Forest Can Do About Ozone.)
Trees reduce urban runoff and erosion by storing water and breaking the force of rain as it falls. The USDA reports that 100 mature trees can reduce runoff caused by rainfall by up to 100,000 gallons!
Trees also absorb sound and reduce noise pollution. This is especially important for people who live near freeways. In some cases, a well planted group of trees can reduce noise pollution by up to 10 decibels. (Source: New Jersey Forest Service.)