Oct. - Dec., 2007
Valuing Urban Trees
When the University of Texas was building a dormitory last year, an unusual sign hung nearby. “Do not discard or pour paint, mortar, trash or any construction material or debris on this tree,” it declared. “The replacement value of this oak tree is $90,000.”
Strange but true: the trees in American backyards may be worth far more than the cars in the front drive, at least in theory. Much depends, of course, on what sort of trees they are. In Nebraska a sugar maple is worth more than an oak, according to a 2004 guide. Trunk size, the tree's condition, its species and location—one in New York City will be worth more than a comparable specimen in Ellington, MO—will all affect values.
Amid fears of global warming, tree hugging is on the rise, not least among politicians. Al Gore has made tree planting central to his message for the Live Earth jamboree on July 7th. Michael Bloomberg has plans to plant 1million trees in New York, which will further boost property values and clean the air.
Of course, no amount of urban oaks can make up for the loss of rainforest in Indonesia—but that has not stopped cities from boasting about the value of their greenery. A recent “tree census” in New York City, conducted at the behest of Bloomberg, values the city's nearly 600,000 trees at $122 million. A rough breakdown: $11 million for filtering out air pollutants; $28m saved in energy consumption (less need for air conditioners); $36 million for stemming stormwater runoff; and $53 million in “aesthetic benefits”. The Forest Service values the urban canopy in all of America at $14.3 billion.
What is the use of all these numbers? Bloomberg cannot sell off trees to patch a hole in his budget, after all. They are, literally, a fixed asset. But for politicians, numbers help. By claiming that every $1 put into New York's trees returns $5.60 in benefits, he may find it easier to galvanize Americans to plant more and are for the ones already there.
Source: Economist.com