WASHINGTON, DC (September 5, 2001) –   American Forests (americanforests.org) just announced a self-sponsored national study reporting millions of  trees missing from America’s urban areas due mainly to urban development. From this study comes troubling data showing that many cities are experiencing a tree shortfall that is resulting in a "national urban tree deficit".

  According to the report, an estimated 634,407,719 trees are currently missing from metropolitan areas across the United States as the result of urban and suburban development. These calculations are based on American Forests’ Regional Ecosystem Analyses conducted over the past six years in select cities in the United States.

Using satellite imagery, AF has been able to document the decline of city trees in many areas across the United States.   With "next generation" satellite imagery and the latest in GIS technology, high resolution images clearly show that many cities are becoming “cities of sidewalks and parking lots.”

Interestingly, the average size of an urban tree was determined to be 15 feet tall, 7 inches in bole diameter, and has a crown spread of 15 feet. This is also the size of tree canopy that would fill the best resolution of a high-resolution satellite and therefore can be calculated. 

As an example, the satellite images show Washington DC as having an average tree canopy of 30%. To increase tree cover just 5%, the District would need to plant 551,040 trees. 

 “Most people will be amazed to see that more than 634 million trees are missing from America’s cities,” said Gary Moll, vice president of the organization’s Urban Forest Center. “But it reinforces something that American Forests has been documenting for years: our cities are paying a high price for the reduction of tree canopy. As trees are lost, so too are the environmental and economic benefits they provide relative to reducing stormwater runoff, air pollution, and energy usage. The good news is that cities can now use high-resolution imagery to see almost every tree in every neighborhood and determine where and how tree canopies can be increased in their communities.”

 Studies were conducted in the following cities and used to determine the National Urban Tree Deficit.  You will see in each case the extent of loss as shown by satellite imagery:

• Denver, CO (pdf)

• Houston, TX (pdf)

• Dade County, FL

• Washington, DC

• Seattle, WA

• Chattanooga, TN

• Roanoke, VA

• Atlanta, GA

• Canton-Akron, OH

• Milwaukee, WI

The study, called “Gray to Green: Reversing the National Urban Tree Deficit”, was conducted in cooperation with the USDA Forest Service, which has supported American Forests’ research and satellite analysis efforts. The Casey Trees Endowment Fund, a foundation established by Washington, DC, philanthropist, Betty Casey, also funded the report.