Abstract The present work took care of the frictional resistance developed between the fill material and mats used as soil reinforcement which are made of locally natural materials . These natural materials are locally available plant organs , which are cheap and abundant , and is expected to result in lower construction cost . The angle of friction is 0.77Øbetween these plant mats and the sand , where is the angle of internal friction of sand . The asphalt bitumen used as a protection coat against moisture and destructive organs , was found to result also in increasing the angle of friction between these mats and the sand to 0.88Ø.