EPA plans to scrap landmark climate policy
The Trump administration plans to withdraw a key scientific finding, which would strip the US government of its authority to regulate greenhouse gas emissions and fight climate change.
unbranded – Newsworthy
On a gray January morning, in a muddy right-of-way near the Kentucky Exposition Center, a crew of contractors worked a half-dozen bald cypresses into the earth, part of a project in anticipation of a much warmer future.
The bald cypress is native to much of the Gulf Coast and across riverine swamps of the Deep South. It’s adapted to warm climates, but is also known to withstand subzero temperatures and winters as far north as Canada.
It’s one of several species TreesLouisville is hauling up from nurseries in dry Oklahoma and humid Georgia in a mission to identify trees capable of thriving both in Louisville’s warming summers and its cold winter months.
Average summer temperatures in Louisville have increased by more than 3 degrees from 1970-2022, according to a Climate Central analysis, a trend experts expect to continue amid unchecked global emissions of greenhouse gases. By mid-century, federal climate projections suggest far more days of extreme heat in Jefferson County compared to historical averages, threatening public health and productivity.
As Louisville’s climate shifts, trees adapted to hotter, southern regions could be hardy additions to the city’s existing canopy. TreesLouisville said it is also experimenting with southern elms, blackgums, hickories and various oaks ― including “familiar names that are native to Kentucky, but sourced from farther south” ― and evaluating the success of southern species planted in decades past.
“Trees that prove successful will be introduced to wholesale nurseries,” the group said, “making them available in commercial quantities for broader use across the city and region.”
A lack of robust tree canopy contributes to the city’s oppressive heat, in the urban core and beyond. By diversifying the city’s tree species with more heat tolerance, in addition to the region’s existing species, advocates hope to cultivate a sustainable canopy that will survive drastic changes in Louisville’s climate.
But building up a diverse, resilient tree canopy necessitates planning decades ahead. Oak trees, for example, may take up to a century to mature. Many of the decisions made on Louisville’s tree canopy today will determine the shade and ecological benefits available to future generations.
“These trees are an investment in Louisville’s next 100 years,” said Cindi Sullivan, executive director of TreesLouisville, in a statement. “As our city becomes hotter, we have to plan now for the trees that will shade our neighborhoods, cool our streets, and protect public health in the decades ahead.”
The decades-long tree canopy mission
Urban foresters and advocates count trees as part of Louisville’s critical infrastructure. The city’s tree canopy intercepts stormwater, filters air pollutants and absorbs carbon. Trees can lower energy bills by cooling neighborhoods, both through shade and evapotranspiration, the process by which plants release moisture into the air. In a past assessment, Louisville’s tree canopy was found to save the city an estimated $330 million every year.
Existing tree canopy, however, is insufficient across much of Jefferson County, based on recent surveys, and inequities have persisted. Wealthier, whiter neighborhoods tend to have higher rates of tree canopy, while thin canopies disproportionately leave neighborhoods of lower median incomes without an important shield from summer heat, air pollutants and flooding, The Courier Journal previously reported.
Warming summers threaten to deepen the racial and socioeconomic disparities in Louisville’s tree canopy, urban heat and the related strain on public health.
The southern trees project is moving forward as Louisville seeks to sharpen its tree canopy strategy. Last year, officials released a Louisville Urban Forest Master Plan, involving other stakeholders, like the city’s Urban Forestry division and Louisville Grows, to guide efforts in the coming years.
The city also announced it would use artificial intelligence to conduct a survey of park and street trees in public rights-of-way. Lack of staffing and resources has made it a challenge for city staff in Urban Forestry to keep up with the inventory and health of every tree in Louisville’s parks and lining the city’s streets, The Courier Journal previously reported. And without proper care and attention, the city’s tree canopy could be more vulnerable to pests and disease, which can also grow more menacing in a warmer climate.
The southern tree plantings are driven, in part, by concern for how extreme heat will affect existing species in the region.
“Temperatures are rising so quickly,” says a TreesLouisville report on the project, “that our local tree species may not be able to adapt in time.”
Trees planted in Louisville soil today have the potential to offer benefits for centuries, said Mike Hayman, special project manager for TreesLouisville involved in the southern tree effort. And by not planning far into the future, Louisville risks “wasting a lot of the benefit” trees provide, he said.
Stepping away from the bald cypress planting and speaking up over the road noise, Hayman also stressed the value of planting large-canopy trees, and implementing them in landscape planning and tree planting efforts across the city.
“There’s many forms of beauty. There’s flowers, there’s fall color, there’s structure,” he said. “There’s a tendency among people to plant small, ornamental trees instead of canopy trees … We can do both.”
Connor Giffin is an environmental reporter at The Courier Journal. Reach him directly at cgiffin@courier-journal.com or on X @byconnorgiffin.