In The Washington Post’s (WaPo) article, “Climate change is coming for D.C.’s trees, and the city won’t look the same,” the authors claim that climate change is killing off Washington, DC’s tree canopy. This is false. While the article mentions other effects that contribute to the decline of the urban tree canopy, they miss or dismiss the primary causes, preferring to blame climate change instead.
The authors argue that rising temperatures and erratic weather patterns are forcing arborists to abandon native species in favor of more “climate-tolerant” trees from the southern United States. The Post asserts that without urgent adaptation, the District’s iconic maples, lindens, and elms could “vanish by 2100.” It also states that “urban development and climate change have contributed to the annual loss of thousands of D.C. trees and threaten the long-term survival of some of the region’s native tree populations.” That may sound convincing, however, in fact, it is deeply misleading.
The majority of DC’s tree stress has little to do with global climate change. Rather, urbanization is the culprit. The city’s heat, pollution, and dense infrastructure have transformed what was once a temperate forest into an artificial microclimate. This is the urban heat island effect (UHI) at work. As Christy and Spencer demonstrated in their peer-reviewed study in the Journal of Applied Meteorology and Climatology, as much as 65 percent of apparent “warming” in urban areas is attributable solely to human development, not global greenhouse gases. Pavement, buildings, and waste heat raise nighttime temperatures, putting added stress on trees that evolved in cooler, more permeable soils.
As Climate at a Glance: Urban Heat Islands notes, “most of the apparent warming in U.S. cities results from localized effects of urbanization, not global climate change.” This localized heating can be several degrees higher than in nearby rural areas, making it a huge stressor for trees already dealing with limited water and root space.
In one sense, WaPo is right that “the city won’t look the same.” But that change will come from bulldozers, power lines, and misguided policy, not carbon dioxide. Construction sites, compacted ground, and impervious surfaces also disrupt local hydrology. Runoff channels water away from roots, while soil compaction limits oxygen exchange. WaPo acknowledges this fact in passing, but downplays the implication that “urban development and construction … can compact soil and hurt root health.” These are direct human management problems, having nothing to do with planetary climate collapse.
Air pollution compounds the problem. Elevated levels of ground-level ozone and particulates can clog or damage the stomata on tree leaves, the small pores that allow trees to “breathe.” When trees are bathed in exhaust, industrial emissions, and urban dust, their stomata often close prematurely to prevent water loss, impairing photosynthesis. The resulting “stomatal overload” is a documented stress response common in polluted environments, especially in cities like DC that sit in traffic corridors. The WaPo ignores this entirely, instead blaming “hotter summers and milder winters.”
Another unacknowledged factor in the arboreal landscape in DC is the city’s own planting choices. Many of the trees in DC’s streetscape — London plane trees, Japanese zelkovas, littleleaf lindens, and the famous Japanese cherry blossom trees — are non-native ornamentals, chosen for aesthetics or fast growth rather than ecological fit. Non-native species often struggle with local pests, soil chemistry, and seasonal patterns. When they fail, journalists may hasten to blame climate change, but really it’s simply poor arboreal planning.
To make matters worse, the city’s tree canopy data are influenced by shifting species selection policies. The Urban Forestry Division is now prioritizing trees from warmer regions like the Southeast—species such as the overcup oak and the swamp white oak—based on assumptions that DC’s future climate will resemble Atlanta’s. But these projections are built on notably flawed computer climate model outputs, not observation. The same models that exaggerate global temperature trends now serve as landscaping guides. There’s a certain irony in “saving” DC’s trees by importing ones that never belonged there.
Meanwhile, the biggest real threat to Washington’s trees isn’t carbon dioxide, it’s the chainsaw. The Post itself reports that “the District has removed more than 37,000 trees over the last five years,” many for development projects. When you cut down a 100-year-old oak to make way for a bike lane or stadium, the resulting loss of shade and soil stability is not the atmosphere’s fault, it’s the city’s.
The “climate change is killing trees” narrative also conveniently omits that CO₂ is plant food. Hundreds of studies and field research show that elevated carbon dioxide concentrations enhance tree growth, improve drought tolerance, and increase biomass. NASA satellite data have even documented a global “greening” trend over the past 40 years as a result of higher CO₂ levels. If carbon dioxide were truly the villain, DC would be losing green cover, not gaining it. Yet the District’s canopy has remained stable at roughly 37 percent for years, exactly the same figure the article cites, despite massive clearing for development.
If Washington, DC wants a healthier urban forest, the answer isn’t to “fight climate change,” it is to manage urban stress. Expand green space. Loosen compacted soils. Plant tree species adapted to the local environment, not projections of future ones. Also, stop pretending that every environmental problem is a symptom of global warming, aka climate change.
The Washington Post’s story may make for poetic reading, but it’s science fiction masquerading as environmental journalism. The real issue is not a mildly warming world—it is a city that’s paved, polluted, and hostile to trees.
Anthony Watts
Anthony Watts is a senior fellow for environment and climate at The Heartland Institute. Watts has been in the weather business both in front of, and behind the camera as an on-air television meteorologist since 1978, and currently does daily radio forecasts. He has created weather graphics presentation systems for television, specialized weather instrumentation, as well as co-authored peer-reviewed papers on climate issues. He operates the most viewed website in the world on climate, the award-winning website wattsupwiththat.com.
Originally posted at ClimateREALISM
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