Man-made composite materials have generated a wealth of studies in the community of wave physics over the past 20 years, as they can have properties that cannot be found in natural materials. It is now well accepted that the properties of these propagation media stem from two distinct origins : the ordered or disordered spatial distributions of their constituents, and the resonant or non-resonant nature of their unit cells. When waves propagate in a composite media that has a structural (...)

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Note that forests have been studied in the 1990’s for their scattering properties with respect to acoustic waves in air (Price et al, 1988). However, the poor sensitivity of microphones and the difficulty of setting up a large number of acoustic sources and microphones under outdoor conditions has limited such an analysis to the measurement of an attenuation coefficient associated with both foliage and trunk scattering. More recently, the acoustic properties of a dense collection of (...)

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