The finite-length multi-layer dielectric cylinder is used to model the trunk.The electromagnetic scattering model for adjacent trunks and sphere above a rough surface ground plane is analyzed by using the reciprocity theorem.The validity of the method is checked by numerical computations based on the moment method.The influence of randomly distributed trunk on the scattering pattern of sphere is discussed at L

C and X bands.It is shown that the low frequency can be used for the purpose of target detection buried in a discrete random media.