A grass product that is substantially protected against or free from insect infestation as by certain soil grubs or the like and method for manufacturing the same. The grass product may be manufactured as sod or grassland and cut into suitable units to be transported and used as a covering for lawns, terraces and the like previously prepared to accept them. Alternately, the grass product may be manufactured on top of existing sod such as in a lawn. The grass product comprises an upper layer of rooting material, a lower layer of sod or rooting material containing grass roots and/or seeds, and a nondegradable screen of a predetermined mesh size interposed between the upper and lower layers. The screen has a predetermined mesh size which prevents insects larger than the mesh from passing from the upper layer into the lower layer and vice versa. The grass blades existing in the sod or formed by germination of the seeds travel upwardly through the screen and upper layer, and the grass roots travel downwardly into the lower layer to form the grass product. Since the roots are below the screen, any insects larger than the mesh size are prevented from passing from the upper layer into the lower layer to eat the roots or to lay eggs which subsequently hatch as root-feeding larvae, and residual insects in the sod are prevented from passing through the screen to the surface of the upper layer.