5 trees to cool cities: biodiversity to the rescue of real estate in the face of urban heat islands

Faced with this challenge, the most effective response remains large-scale greening, and in particular urban trees, which act through two complementary mechanisms:

• Shading: direct interception of solar radiation on façades and outdoor spaces.
• Evapotranspiration: by drawing water from the soil and releasing it through their leaves, trees actively cool the surrounding air—functioning as a true natural air conditioner without energy consumption.

However, not all tree species perform equally well in the climate conditions expected by 2050. Below are 5 species selected for their climate resilience and effectiveness in dense urban environments ⁸.

Native to the Mediterranean basin, the Mediterranean hackberry (Celtis australis) is well suited for Europe’s future climate. It tolerates extreme heat, compacted soils, and low-humidity urban environments. Its dense foliage provides excellent solar radiation interception. Highly resistant to diseases and wind, it is a low-maintenance tree that supports optimized asset management.

• Heat island benefit (UHI): withstands extreme heat and poor or compacted soils. Its dense foliage provides excellent solar radiation interception.
• Resilience: highly resistant to diseases and very wind-resistant.

Among all oak species, this one is the most suited to hot, dry summers, significantly outperforming the native pedunculate oak (Quercus robur) in urban environments. Its very large, deeply lobed leaves maximize evapotranspiration surface area and actively cool the air. It also shows good tolerance to calcareous and urban soils, making it ideal for green spaces around residential buildings or office campuses.

• Cooling benefit: its very large, lobed leaves provide a high evapotranspiration surface, actively cooling the surrounding air.
• Resilience: : good tolerance to calcareous and urban soils.

Commonly planted in cities in Southern Europe, the Japanese pagoda tree adapts very well to northern France and Belgium. Its relatively fast growth makes it a visible-return investment. An additional advantage: its late summer flowering supports pollinating biodiversity during peak heatwaves, a strong asset for biodiversity reporting. It also shows excellent resistance to urban air pollution.

• Heat island benefit (UHI): relatively fast growth and late summer flowering that supports biodiversity during heatwave periods.
• Resilience: excellent resistance to urban air pollution.

A true “living fossil,” the ginkgo is one of the most biologically resilient tree species. It is virtually indestructible (insects, fungi, pollution, extreme thermal stress: none of these significantly affect it). Its carbon storage capacity is high. Although its evapotranspiration is moderate, it provides durable shading where other species would fail—making it a key pillar of long-term urban canopy strategies.

• Cooling benefit: high carbon storage capacity. Its guaranteed survival under extreme conditions makes it a pillar of durable urban canopy cover.
• Resilience: virtually indestructible (insects, fungi, pollution, and even severe thermal stress).

• Cooling benefit: its large leaves and crown structure create a strong “parasol effect.” Under a linden tree, perceived temperature can drop by several degrees thanks to intense leaf transpiration.
• Note: it is important to de-seal (de-pave) tree pits to allow it to access the water needed for effective cooling.

9 – Bruxelles Environnement. (s. d.). Végétaliser pour refroidir les espaces urbains : Des solutions fondées sur la nature. Consulté le 1er avril 2026