NURTURING parks and green spaces has long been vital in making urban areas more pleasant to live.
But untamed and ill-considered trees and vegetation may be damaging some of our most iconic heritage buildings, scientists have warned.
They reveal that the substances mix with air pollutants to produce corrosive gases capable of eroding stone, concrete and steel.
Limestone buildings, such as the Houses of Parliament and Westminster Abbey, are particularly vulnerable, they say.
The damage is mainly caused by ground level ozone, which is formed when volatile organic compounds given off by plants are broken down in sunlight and react with the pollutant nitrogen dioxide.
They found sycamore, maple and Douglas cause some of the worst damage.
Dr Abhishek Tiwary, who carried out the research with Surrey University, stressed green spaces play a big part in reducing pollution in cities, but urged civic chiefs to properly plan them.
He added: “Such consideration might improve the structural longevity of buildings of importance.”