As summer temperatures soar, we all appreciate shade trees. A healthy tree canopy of diverse species cools surface and air temperatures, removes air pollutants, provides wildlife habitat, and absorbs stormwater runoff, all while being visually appealing and raising property values.
Trees are, in fact, essential to a livable community. Many urban dwellers live in heat islands, where concrete, buildings, vehicles and air conditioners elevate air temperatures. The results: higher utility bills, increased greenhouse gas and pollutants, physical discomfort, and impaired health.
Within cities, some neighborhoods are hotter than others, forming intra-urban heat islands. These tend to be lower-income neighborhoods, subjecting their residents to greater discomfort and health risks, including asthma. Intra-urban heat islands also deter people from walking or bicycling on errands (try walking to the Iowa City Post office on a hot day!)
Many cities are now combating heat islands by mapping presence and absence of tree canopies and by diversifying tree species to increase canopy resilience now and over the next 50,100,150 years as our climate warms. Importantly, these efforts are focusing attention on improving the equitability of environmental and aesthetic qualities for all.
Here in Johnson County, where we’ve lost many street trees to emerald ash borer and the 2020 derecho, a number of programs encourage residents to plant their own. Iowa City offers its Root for Trees program, which makes vouchers available for 50% off a tree at participating nurseries. The next cycle in the Roots for Trees program opens in September 2023.
While Root for Trees is for Iowa City residents only, Coralville offers a tree purchase program called Branching Out, and the North Liberty Parks Department holds tree planting workshops.
A few words of caution: If you wish to plant in the public right-of-way in front of your house, many cities, including Iowa City and Coralville, require a permit. Before you dig, check for overhead wires, and be sure to call Iowa One Call at 811 or 1.800.292.8989 to locate and mark utilities.
If you are not in a position to plant your own tree, you can still help develop our canopy. Trees Forever, based in Marion Iowa, offers educational and volunteer opportunities, and Project Green, which has a fifty-year history of planting trees in Johnson County, also needs volunteers.
Or become a citizen scientist! Iowa City this month has kicked off its Spot the Hot program, a campaign to map urban heat by gathering temperature data. If you missed the opening event on June 10, you can sign up online to help Spot the Hot.
Where are the heat islands in your part of town? Where would you like to see more trees? Let us know by e-mailing us here!
Read the entire Good Energy Newsletter, Summer 2023