Ultra-wideband (UWB) radio transmission measurements have been used to determine the moisture content of wood chips using a time domain technique. Wood chips have been found to have birefringent dielectric properties acting as an anisotropic dielectric effective medium. Birefringence in wood chips occurs because of the orientation and the shape of wood chips, and microscopic structures of these objects, like wood fibers. The birefringence gives rise to two different wavefronts along the principal axes that have different dielectric properties. Each wavefront has a specific time-domain signal, that can be used to determine the moisture content. In industrial applications, for example in measurement on wood chips in trucks, the vertical polarization direction is the preferable polarization because this signal has higher signal-to-noise ratio (SNR), which makes the signal more identifiable at longer distance (2-3 m). Thus, UWB radio transmission measurement and time-domain analysis is a robust technology to investigate larger containers of wood chips and to determine the moisture content with high accuracy.