The Wood Planks with Grounds set has 3 scene subsets, and 7 separate plank objects with 3 Iray materials for each plank, and a frame with 3 Iray materials, as well. There is also a plank plane that comes with 8 Iray shaders, and 3 grounds covered in grass and stones.
https://www.daz3d.com/wood-planks-with-grounds
