In honor of Arbor Day the Morton Arboretum tagged several trees around downtown Chicago with price tags that list the value of the tree in terms of environmental benefits it will provide over the next 15 years. They began with a list of species of trees. Next, they entered the data into the National Tree Benefit Calculator. They estimated each tree's annual growth rate over the next 15 years and calculated a dollar value for that tree through 2025. Look for the trees with the green price tags on them around the Loop, they'll be on display until May 13th, 2011.
Inspired by their example I set out to calculate the value of the Northern Catalpa tree pictured here. I learned that this Northern Catalpa tree provides and overall benefit of $62.00 every year. It will intercept 571 gallons of stormwater runoff this year. It will increase the property value of the small commercial business it is located in front of by $34 this year. It will conserve 24 Kilowatt/hours of electricity for cooling and reduce consumption of oil or natural gas by 11 therm(s). It will reduce atmospheric carbon by 128 pounds. Pretty cool, eh? You can follow the directions here to calculate the value of a tree on your property or in your neighborhood.