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A rapid development of urban infrastructure in past decades together with a relatively recent growth of awareness of its impact on the natural environment result in an increased interest in non-destructive ground interrogation methods. Underground space in cities is very densely populated by various types of infrastructure but it is also a home for tree roots. Tree root damage is a very well known issue in civil engineering and can emerge as road surface fracture, building foundations disintegration or pipe penetration, among others. For new developments it is essential to avoid any interference with roots not only since they may cause costly damage but also because their discovery during construction may pose additional complications related to the natural environment protection. In this paper we investigate the feasibility of using a vibroacoustic method for tree root mapping. The core of the idea is that the mechanical waves induced by an excitation mechanism acting on the tree trunk propagate to the roots and then radiate into the surrounding soil. Owing to that, the response measured at the ground surface contains the contribution of waves radiating from roots and can be used for mapping their extent. We conduct a finite element analysis of the trunk-root-soil system determining the dominant wave fields contributing to the ground surface response. Then, we report a set of experiments on a 'purpose-built' physical root model. An instrumented root buried at a known depth is excited using various techniques with both root and ground responses acquired. These preliminary results both demonstrate the technique and shed light on related challenges and limitations.