Daily Quiz — 26 Sep 2026

Trees in the city

Cities around the world are discovering that trees are not merely decoration. A mature tree can lower the temperature of the street beneath it by several degrees on a summer afternoon, reducing the need for air conditioning in nearby buildings. Trees also absorb rainwater, which eases the pressure on drains during heavy storms, and their leaves trap dust and some pollutants from the air. Yet urban trees face a hard life. Their roots are squeezed by pavements and pipes, their bark is damaged by vehicles, and they are often cut down to widen roads. Many are planted without a plan for watering or care, so a large number die within a few years. Some city governments now treat trees as part of their infrastructure, like roads and water pipes. They count them, record their health and budget for their maintenance. The results are encouraging: streets that are cooler, quieter and more pleasant to walk along, and residents who take pride in the green spaces around their homes.