When Joyce Kilmer wrote, "I think that I shall never see a poem lovely as a tree," he probably wasn't thinking about carbon sequestration, stormwater management and water filtration. But we now know that urban trees do much more than create pleasant views for city residents.
"The urban forest is a major measure of the ecological health of a community," said Shannon Halley, Associate Director of TreeFolks, an Austin non-profit dedicated to planting more trees and educating people about their value. "Trees provide shade, reducing the urban heat island effect. They inhale large quantities of carbon dioxide, a major greenhouse gas, capturing it and holding it in the soil instead of allowing it to escape to the atmosphere."
Trees and their root systems also slow the rush of storm water and filter it of pollutants, Halley said.
The City of Austin is now asking residents to count trees as part of the Great Austin Tree Roundup. A tree inventory will allow the city to value the forest accurately-placing a dollar value on the ecoservices trees provide helps people understand their importance and the need to conserve them.
Working with TreeFolks, the Wildflower Center created the web-based inventory which provides a quick and easy way for people to record the trees in their yards and beyond.
Once the tree is mapped, it's easy to see the dollar value. For example, a large plateau oak, 136 inches in circumference, provides $343.98 in annual benefits, including approximately $181 in stormwater benefits, $72 in property value enhancement, $32 in electricity savings and $21 in air quality benefits. By sequestering 2,603 pounds of carbon, this oak prevents 360 pounds of carbon dioxide from entering the atmosphere.
The inventory started out with nearly 20,000 of the estimated 1 million trees already entered, thanks to previous inventories by the City, The University of Texas at Austin and the Wildflower Center. However, a complete professional inventory would require a major commitment of city staff and tax dollars.
"We had experience in creating a citizen-driven, web-based inventory," said Dr. Damon Waitt, the Wildflower Center's senior botanist and a former member of the Austin Urban Forestry Board, "since we had created an interactive web tool for the Invaders of Texas, volunteers who identify and map invasive plants.
TreeFolks had a small grant and asked for Wildflower Center help in creating the web tool. On November 18, the Austin City Council approved a proclamation calling on all citizens to participate in mapping the trees on their own properties, streets, school yards and businesses.
"We recognize that our urban forest provides services essential to the quality of our lives and the livability of our city, as well as the protection of our climate," the proclamation said.