Plants that are found on the sides of roads that show a high frequency of traffic are usually seen to be sickly looking. They never quite achieve their optimum height as per the species or even grow as much as they would in foliage in the woods. Scientists have always said that the emissions from the vehicles on the road pollute the area so badly that the plants end up stunted.

Researchers at the University of Surrey are looking into another aspect of this by studying hedges that are planted on the edge of roads with an aim to reduce air pollution in the region. Hedges are a much more hardy plant species and study showed interesting results. The researchers studies areas which had only hedges as well as some which had a combination of hedges, trees and shrubs.

It was found that the areas with just hedges were the most effective at reducing air pollution. There was a 63% reduction in black carbon in these areas. Also the ultra fine and sub micron particles were also reduced in the size in the area. This science experiment suggests that it may be better to plant hedges near roads than trees or shrubs.