To date diverse soil moisture sensors have been commercially available but all of these are at point-scales of centimeters-to-decimeters with limited volume of sensitivity (VOS). In many cases, the spatial variability of soil moisture distribution can be considerably larger than the VOS. A novel motorized dielectric PVC-tube sensor prototype was presented for horizontally scanning soil moisture content (maximum scanning length 380cm). The sensing probe was cylindrical and thus can be mobilized through the PVC tube which was horizontally embedded at a certain depth of soil layer. In order to prove its technical feasibility, two case applications associated with drip emitter tests were presented as well. The experimental results demonstrated that the applications were potential to support the model validation for simulating water migration, monitor soil water variation in root-zone accompanying plant growth, provide one-dimension data for precision irrigation and evaluate the effectiveness of irrigation equipment.