The Case for More Urban Trees

*The net cooling effect of a young, healthy tree is equivalent to ten room-size air conditioners operating 20 hours a day.
*If you plant a tree today on the west side of your home, in 5 years your energy bills should be 3 percent less. In 15 years the savings will be nearly 12 percent.
*One acre of forest absorbs six tons of carbon dioxide and puts out four tons of oxygen.
*A number of studies have shown that real estate agents and home buyers assign between 10 and 23 percent of the value of a residence to the trees on the property.
*Surgery patients who could see a grove of deciduous trees recuperated faster and required less pain-killing medicine than matched patients who viewed only brick walls.
*In one study, stands of trees reduced particulates by 9 to 13 percent, and the amount of dust reaching the ground was 27 to 42 percent less under a stand of trees than in an open area.

Among other things, he calculated that "for a planting cost of $250-600 (includes first 3 years of maintenance) a single street tree returns over $90,000 of direct benefits (not including aesthetic, social and natural) in the lifetime of the tree."

Street trees create slower and more appropriate urban traffic speeds, increase customer traffic to businesses, and obviate increments of costly drainage infrastructure. In at least one recent study (reported after Burden’s analysis), trees were even found to be associated with reduced crime.

I think some of the most important benefits, though, are felt emotionally. Burden puts it this way:

~Urban street trees provide a canopy, root structure and setting for important insect and bacterial life below the surface; at grade for pets and romantic people to pause for what pets and romantic people pause for; they act as essential lofty environments for song birds, seeds, nuts, squirrels and other urban life. Indeed, street trees so well establish natural and comfortable urban life it is unlikely we will ever see any advertisement for any marketed urban product, including cars, to be featured without street trees making the ultimate dominant, bold visual statement about place.~

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