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In this article, we focus on ground transportation noise abatement and more precisely road traffic noise control. From literature as well as our own experience in this field we aim at determining in which planting schemes are trees or forest strips beneficial to environmental noise abatement, for which expected noise attenuation and with which good practices.We start by a brief point on French regulation on road noise management and we present a synthetic review of main attenuation processes observed when sounds propagates through areas with trees: ground, diffusion and refraction effects. Then we consider some typical landscape configurations studied in the scientific literature and we provide with expected acoustic impact: a forest strip along a road infrastructure, a row of trees along a noise protection and trees in the city. We finally give a set of recommendations of correct use of trees and forest strips as an element to the improvement of outdoor sound environment. Our advice is to plant broadleaved evergreens or a mixture of broadleaved evergreens and coniferous, with a minimum density of 0.25 tree/m2. We also advise to cultivate the ground before trees planting and to use well-rotted organic matter. On the other hand we do not recommend planting trees at the top of earth berms.