The shading model was implemented in Renderman Shading Language. This shading model can capture all the physical appearances of grass blades. A BRDF model based on [8] was applied on the front side to calculate the reflectance of thatched grass blades. In addition, the back side used a multipole BSSRDF based on [9] to capture the diffuse and translucency of thatched grass. A scar on each blade used texture mapping. This enhanced the rendered image to look more natural and realistic.