Nature & Environment

How Much a Tree is Worth: Urban Forests Valued at Billions in Carbon Storage

Catherine Griffin
First Posted: May 08, 2013 09:45 AM EDT

How much is a tree worth? Apparently its value skyrockets when it's located in a city. According to the U.S. Forest Service, urban trees hold an estimated value of $50 billion as they provide valuable, environmental services such as storing carbon.

Trees don't just beautify urban areas. They also help clean up polluted air and store carbon in these locations. In this latest study, researchers found that urban trees actually store an estimated 708 million tons of carbon. In addition, they discovered that annual net carbon uptake by these trees is estimated at 21 million tons--that's $1.5 billion in economic benefit.

"With expanding urbanization, city trees and forests are becoming increasingly important to sustain the health and well-being of our environment and our communities," said U.S. Forest Service Chief Tom Tidwell in a news release. "Carbon storage is just one of the many benefits provided by the hardest working trees in America."

In order to determine exactly how much urban trees were worth, researchers needed to find out how much carbon these trees could store. They used urban tree field data from 28 cities and six states. They then combined this data with national tree cover data in order to estimate total carbon storage in the nation's urban areas.

This carbon storage is certainly a useful tool in urban areas, and also shows that forestlands aren't the only places capable of mitigating environmental impacts. In previous studies, the national estimated carbon storage by trees in forestlands was 22.3 billion tons. Yet this newest study shows that urban areas also contribute to this number; it bumps up the national amount of carbon stored to 22.7 billion tons.

Yet not all areas have the same percentage of tree cover in urban areas. The study also found that the states with the greatest amount of carbon stored by trees in urban areas are Texas, Florida, Georgia, Massachusetts and North Carolina. Encouraging other states to plant more trees could certainly help expand carbon storage in the nation.

"I hope this study will encourage people to look at their neighborhood trees a little differently, and start thinking about ways they can help care for their own urban forests," said Tidwell in a news release.

The findings are published in the journal Environmental Pollution.

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