The real dollar value of felled trees Part 3 of a seriesby Matthew Schacht, special to the Columbia Heart Beat
COLUMBIA, Mo 11/8/13 (Feature) -- John Fleck says the technology exists to put a price on tree removal.
To demonstrate, the City of Columbia GIS analyst uses a free, open-source software called CityGreen to approximate how many gallons of water an acre of trees holds in its leaves; how much air pollution a big oak removes; and how much it's all worth in dollars and cents.
Trees in the Hinkson Creek watershed remove about 680,000 pounds of nitrogen-based air pollution and 2.4 million tons of carbon-based pollution per year -- a priceless benefit to human respiratory health. And by soaking up water that could otherwise flood streets and sewers, they also save about $120,000 in storm water costs.
The numbers aren't perfect, as Fleck readily admits. But CityGreen offers a ready demonstration to skeptical superiors, and the science underlying the calculations is valid, says forester Josh Behounek.
To measure storm water benefits, researchers dry leaves in ovens to calculate the amount of moisture they hold, he explains. Lost trees can also mean lost tourism spending, on which researchers put a dollar amount by comparing consumer behavior and tree proximity. Turns out people spend more money on streets lined with trees.
For number crunching, Behounek -- who consults with cities about the economic impact of tree preservation -- prefers a software called I-tree, an open-source offering from the US Department of Agriculture. "I-tree is peer-reviewed and there's a whole bunch of research behind it," he says. In some situations, "I-tree can prove that every dollar spent on trees saves [the city] four dollars."
Tree loss has short-term effects -- both economic and non-economic -- that are immediately apparent: loss of shade, loss of beauty, loss of the majesty of an oak-lined street in the Fall. And while we can't see storm water retention and pollutant removal in action, tree preservation benefits are almost as immediate.
Longer term impacts, however, may not be apparent for years, soil erosion chief among them.
In 2010, the city of Columbia paid at least $20,000 to protect a 24-inch diameter sanitary sewer pipe (pg. 102) exposed along Hinkson Creek as part of an estimated $180,000 creek stabilization project. The EPA monitors Hinkson Creek as an impaired waterway, citing tree loss and development as major causes of creek-side erosion.
Recent studies suggest deforestation also impacts public health long term. Communities with tree loss suffer higher mortality rates, claims a 2012 study, "The Relationship Between Trees and Human Health". Deforestation may also be related to human illness, say Harvard Medical School researchers.
Despite the short and long-term impacts, tree removal "is not considered" in City Hall's building and construction decisions, says Columbia director of development Tim Teddy.
Instead, Teddy's office is chiefly concerned "about whether we have the budget to process a development plan. Do we have enough staff?"
That doesn't mean city officials aren't interested in the real-dollar costs and benefits of tree preservation. But Columbia could do a better job calculating long-term impacts, according to a 2013 city progress report. About two-thirds of residents are dissatisfied with how the city is managing growth, the report noted.
Vowing to improve Columbia's planning, the report claims "over the next three years, we will inject more balance and transparency into the City's growth management processes. Goals include long-term fiscal impact statements for development proposals."
But does a grim future for Columbia's woods lie ahead regardless? That question explored next.
Creek photos by Matt Schacht and Kile Brewer
READ PART 1