By Dave Coulter
Last week E and I attended a gathering at Morton Arboretum where they outlined their efforts on behalf of our regional tree population. On the way out the door they handed us these nifty cards where - by way of the National Tree Benefit Calculator - one can estimate the economic value of the environmental services that trees provide.
So, over the weekend we teased out the numbers (I'd suggest using Internet Explorer....Google Chrome didn't work for me) for a couple of E's parkway trees, and displayed the big green tags proudly. The numbers that came out were interesting, and do provide a basis for quantifying the benefits that trees provide, particularly in urban areas.
It seems to me that people used to intuitively understand the value of a tree. But these are tough economic times, and these types of tools for calculation arose of out of the need for communities to justify their tree care budgets. Like their human counterparts, trees must now justify their existence to their particular board of directors.
The subject of ecosystem services seems to come up routinely if you read any environmental articles. It should be obvious that human life is dependent on functioning ecosystems, but putting a realistic dollar number on such items can be a slippery task. I think these benefits are more tangible to appreciate once they're gone, i.e. if all the salmon fisheries have collapsed this would equate to "x" number of lost income and jobs. It's no longer abstract when the fish are gone and it becomes pointless to gas up the boat.
And I think my clumsy salmon analogy works to help illustrate the problems our urban trees face and values they provide. Along with economic distress we also live in an era of tree loss. We all understand the idea of how delicious salmon is, and it's corresponding price per pound. I hope we can understand more clearly the value of trees, because in the face of myriad pressures we will all be deciding if we want to sit in the shade when we are old people.
So....what are your trees worth to you and your neighbors?