When Safety Makes Cities More Dangerous: An Urban Absurdity

Minh Anh Hoang

Trade Union University, Hanoi, Vietnam

*Contact: anhhm@dhcd.edu.vn

21-05-2026

© Wix

Cities often present themselves as humanity’s greatest achievement—carefully designed systems intended to maximize safety, efficiency, and comfort. Roads are widened, utilities protected, traffic optimized, and infrastructure managed through increasingly sophisticated regulations. Yet a strange paradox has quietly emerged within many modern cities: in trying to protect people from risks associated with urban trees, we may be exposing them to even greater dangers.

Over the past decades, a growing body of scientific evidence has highlighted the immense benefits of urban nature. Green spaces and tree canopies reduce heat exposure, improve air quality, lower risks of cardiovascular disease, depression, and anxiety, and may even strengthen immune function through exposure to healthy soil microbiomes (Feng, Toms, & Astell-Burt, 2022; Feng et al., 2024; Williams et al., 2025). Trees also help create social environments that reduce loneliness by providing places where people can connect, recover socially, and find refuge from stressful conditions.

The importance of trees becomes even more evident as climate change intensifies. Heatwaves are increasing in frequency and severity, while cities themselves worsen the problem through the urban heat island effect. Prolonged heat exposure can damage multiple biological systems and contribute to sleep disruption, reduced physical activity, heat stress, and death. In 2023, heat-related mortality among people over 65 increased by 167% compared with 1990 levels (Romanello et al., 2023). Another study has also linked higher urban temperatures with increases in violent crime (Stevens et al., 2024).

Research suggests that tree canopy can substantially reduce urban heat, but only when sufficient coverage exists. One study found that neighborhoods with approximately 40% tree canopy experienced strongly reduced heat-island effects (Ziter et al., 2019). Yet many cities remain far below this threshold.

Despite these benefits, urban trees are often treated as problems rather than solutions.

Croeser and colleagues argue that many existing urban governance systems unintentionally exclude greenery. Rules designed to protect roads, utilities, and traffic infrastructure frequently frame trees as sources of risk. Tree roots are blamed for damaged pipes, vegetation is removed to preserve sightlines for vehicles, and branches are heavily pruned to reduce unlikely hazards (Croeser et al., 2026).

The situation becomes strangely ironic.

Imagine a city official announcing: “We removed the trees because they were dangerous.” Citizens nod in agreement. The roads become hotter. Heat-related illness rises. Air quality worsens. Neighborhoods become less walkable and more socially isolated. Flood risks increase. Biodiversity declines. Eventually, more residents become ill from conditions associated with heat and environmental stress.

The official then proudly declares: “Good news—we successfully eliminated the tree risk.”

This absurdity emerges because acute and chronic risks are treated differently (Vuong, 2025; Nguyen & Ho, 2026). A falling tree branch is dramatic, visible, and politically costly. It appears on news headlines and generates public outrage. Heat-related illness, social isolation, declining mental health, and gradual ecological degradation are quieter and slower processes. Their causes become diffuse and harder to see (Khuc & Nguyen, 2026).

It does not mean that risks from urban trees should be ignored. Rather, it exposes how systems of reasoning can become trapped within their own logic. When institutions become preoccupied with preventing highly visible but unlikely dangers, they may unintentionally create larger yet less visible harms.

Perhaps the question is not whether trees create risks. The more unsettling question may be whether cities have become so efficient at removing small inconveniences that they have begun systematically designing larger disasters.

References

Croeser, T., et al. (2026). Treeless streets and sleepless nights: How cities overprotect infrastructure and underprotect citizens. Landscape and Urban Planning, 273, 105675. https://doi.org/10.1016/j.landurbplan.2026.105675

Feng, X., Toms, R., & Astell-Burt, T. (2022). The nexus between urban green space, housing type, and mental health. Social Psychiatry and Psychiatric Epidemiology, 57(9), 1917-1923. https://doi.org/10.1007/s00127-022-02266-2

Feng, X., et al. (2024). Show me the money! Associations between tree canopy and hospital costs in cities for cardiovascular disease events in a longitudinal cohort study of 110,134 participants. Environment International, 185, 108558. https://doi.org/10.1016/j.envint.2024.108558

Khuc, V. Q., & Nguyen, M. H. (2026). Cultural Additivity Theory. Available at SSRN 6767760. https://ssrn.com/abstract=6767760

Nguyen, M. H., & Ho, M. T. (2026). The absurdist approach to unveiling possible paradoxical thinking for innovative socio-psychological research. MethodsX, 16, 103910. https://doi.org/10.1016/j.mex.2026.103910

Romanello, M., et al. (2023). The 2023 report of the Lancet Countdown on health and climate change: The imperative for a health-centred response in a world facing irreversible harms. The Lancet, 402(10419), 2346-2394. https://doi.org/10.1016/S0140-6736(23)01859-7

Stevens, H. R., et al. (2024). Associations between violent crime inside and outside, air temperature, urban heat island magnitude and urban green space. International Journal of Biometeorology, 68, 661-673. https://doi.org/10.1007/s00484-023-02613-1

Vuong, Q. H. (2025). Wild Wise Weird. AISDL. https://books.google.com/books?id=C5dDEQAAQBAJ

Williams, C., et al. (2025). Urban green space provision: the case for policy-based solutions to support human health. Medical Journal of Australia, 222(3), 110-113. https://doi.org/10.5694/mja2.52569

Ziter, C. D., et al. (2019). Scale-dependent interactions between tree canopy cover and impervious surfaces reduce daytime urban heat during summer. PNAS, 116(15), 7575-7580. https://doi.org/10.1073/pnas.1817561116