As street trees die, cities search for ways to stay green

Toronto residents are upset. Through-out the 2.6-million population Ontario city and especially in its center, thousands of street trees are dying prematurely, many within a year or two of being planted. Public concern is so strong that last fall the government organized a conference in which 200 municipal personnel spent an entire day discussing the problem with tree experts from throughout North America. Seen from the air, only about 16 percent of the “old” section of Toronto (the part developed before 1945) is under tree cover, down from 22 percent in 1992. And Toronto is not unusual. American Forests, a nonprofit conservation organization, has found that tree cover is declining in many North American urban areas. Based on satellite images of 40 US cities, American Forests reported in 2003 that “urban areas have 21 percent less tree canopy today than they did 10 years earlier.” Tree canopy covers only 12 percent of Buffalo and Lackawanna, New York. Trees shelter less than 20 percent of metropolitan San Diego. (At the other end of the spectrum, one of the lushest cities is Savannah, Georgia, where trees shelter more than 60 percent of the land and buildings.) As tree cover declines, cities

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