To overcome the following problems: wood chips, which are made by crushing wood and laid all over the periphery of a tree etc. so as to be used as a weed inhibiting material for preventing the growth of weeds, cause the growth of the weeds because seeds of the weeds, coming flying from the periphery of the tree etc., adhere to the surfaces of the wood chips or between the wood chips so that their roots can be spread; small pieces etc. cannot be effectively prevented from being scattered and washed away, though the wood chips are prevented from being scattered and washed away, by rolling after the overall laying of the wood chips with the effect of intertwining the wood chips; and colors of surfaces of the wood chips are deteriorated and faded because the surfaces of them are exposed to sunlight, rain, etc.

The wood chips, which are to be used as the weed inhibiting material on the peripheries of the tree, a pole of a street light, a support of a building, a bridge pier, etc., are treated in such a manner that a transparent fibrosed synthetic resin is sprayed on their surfaces.