Interactive map: Planting trees to increase the urban tree canopy in Washington, D.C. - Arbor Day 2010 (washingtonpost.com); Washington, DC

Interactive map: Planting trees to increase the urban tree canopy in Washington, D.C. - Arbor Day 2010 (washingtonpost.com):
It's Arbor Day.
Do you know where the trees are?
The District should look a good bit greener in 25 years if Mayor Adrian M. Fenty realizes his goal of a 40 percent 'urban tree canopy' -- or a tree canopy that covers 40 percent of the city as viewed from above -- by 2035. Right now, the District has a fairly healthy 35 percent canopy, thanks to Rock Creek and Fort DuPont parks. But an effort is underway to plant more on private property in hopes of reaping such benefits as reduced air pollution, improved water quality and less demand for energy during the summer. To reach 40 percent by 2035, the District would need to add more than 2,000 acres of canopy, or about 216,000 trees. Casey Trees, a D.C. nonprofit organization that plants, monitors and cares for trees in the District, has contributed to the cause by planting more than 7,000 trees since 2003.