Sound Barrier suggestions
Planting a Sound Barrier
Vegetation can be used to barrier the effects many problems including noise pollution. As with plantings for wind or visual barriers, the selection and arrangement of the plant material is key to a successful outcome.
Noise reduction is achieved by either deflection or absorption of the noise or a combination of the two. Most hardscape barriers work by deflecting sound (example 1in pic.). To be effective they should be close to the source of the noise as safety allows. With these barriers vegetation serves to soften the visual effect of the barrier and reduce the reverberation of sound. Earthen berms are often used in combination with trees and shrubs to deflect and absorb sound when the available space is limited (example 2 in pic.).
Vegetation alone can be used where adequate space is available. To be effective the planting must be multiple rows to about 40‑75' in depth. Care also must be taken to plant the first row at 50' from a roadway or any area‑ that should not be subject to extra snow deposits.
Conifers or evergreen broadleaf plants will naturally provide the best year around noise reduction. Deciduous trees and shrubs can be added to the planting for variety and added summer noise reduction (example 3in pic.).
Vegetation should be selected for site conditions with special attention to plant selection guidelines section. It is also important to incorporate fast growing plants and long lived plants for a quick and long lasting barrier.
Plant in rows closest to the sound. Chose dense or thicket forming
shrubs that tolerate salt or deicing chemicals and air pollutants.