This paper presents the work carried out in an effort of modelling the scattering and absorption effects of single tree trunks with application to the discrete Radiative Energy Transfer (dRET) based model applications. The assessment of the proposed empirical model was performed against measurements of both metallic and dielectric cylinders, mimicking tree trunks, at several micro- and millimetre wave frequencies, i.e. 9.4, 18.8 and 37.6 GHz. These were carried out in a controlled environment, i.e. an anechoic chamber, so that frequency dependent effects could be evaluated.