If you're trying to take pollution out of the air, choose evergreen trees with smaller leaves. That's according to a new study from the University of Surrey. <br />Researchers from Surrey's Global Centre for Clean Air Research (GCARE) tested ten trees beside a busy main road. They studied which caught the most particles of pollution and which best allowed the rain to wash those particles safely to the ground. <br />It had been thought that leaves with rougher surfaces and minute hairs would catch more pollutants. Yet that wasn't borne out by the evidence.
