This is a debated topic, but the 'Noise abatement in plant monocultures and plant communities' article is a good summary. They concluded that a 12-meter planting, with rows perpendicular to the sound source, can be effective in abating noise pollution.
Select evergreen plants that branch to the ground. Even when you don't have enough space to fully block the sound, a visual barrier of plants provides some relief. Berms are more effective in reducing noise, so often a berming/planting strategy is more effective and more interesting as well!.
Distance, Orientation, and Density matter.
Post prepared by Julie Sherk and Anne Spafford.
Julieta T. Sherk, PLA, ASLA, Professor
Department of Horticultural Science
College of Agriculture and Life Sciences NC State University
Associate Faculty Department of Landscape Architecture
Anne M. Spafford, MLA, ASLA
Associate Professor of Landscape Design
Professor, Department of Horticultural Sciences
North Carolina State University
