Question to the Department for Transport:

To ask the Secretary of State for Transport, what recent assessment he has made of the effect of trees and vegetation in reducing traffic noise levels.

It is well understood that trees and vegetation have a limited effect on noise propagation from roads, and a broad band of densely planted trees is required to significantly reduce noise.

The EC’s 'HOSANNA' research project (Holistic and Sustainable Abatement of Noise by Optimised Combinations of Natural and Artificial Means) has identified and assessed vegetation strategies that could deliver perceptible noise reductions. The project’s findings became available between 2010 and 2013.

The Highways Agency will consider these strategies for use on new or modified road schemes.