Trees Save More Than 850 Human Lives Per Year: Urban Forests Reduce Respiratory Problems

How important are trees? They apparently save lives. Scientists found that trees save more than 850 human lives per year and prevent about 670,000 incidents of acute respiratory systems.

Trees can remove pollution from the air and make it safer to breathe. Yet scientists wanted to know exactly how much trees were actually contributing to human health. That's why researchers took a look at four pollutants: nitrogen dioxide, ozone, sulfur dioxide and particulate matter less than 2.5 microns.

The researchers found that pollution removal is substantially higher in rural areas than in urban areas. That said, the effects on human health are substantially greater in urban areas than rural areas. While trees' pollution removal equated to an average air quality improvement of less than 1 percent, the impacts of that improvement were substantial. In fact, the scientists estimated that the human health effects of the reduced air pollution was worth nearly $7 billion ever year.

That's not all, either. The researchers found that the benefits of trees varied with tree cover across the nation. For example, trees in urban areas are substantially more important than trees in rural areas due to their proximity to people. In fact, the scientists discovered that the greater the tree cover, the greater the pollution removal, and the greater the removal and population density, the greater the value of human health benefits.

"With more than 80 percent of Americans living in urban area, this research underscores how truly essential urban forests are to people across the nation," said Michael T. Rains, one of the researchers, in a news release. "Information and tools developed by Forest Service research are contributing to communities valuing and managing the 138 million acres of trees and forests that grace the nation's cities, towns and communities."

The findings reveal the importance of trees in and around urban areas. If urban forests are planted, then it's possible to potentially improve public health.

The findings can be found online here.