PROBLEM TO BE SOLVED: To provide a ground weight-reducing member for mat plants including a means satisfying both of reduction in the weight of a planting ground and smooth growth of the mat plants when using the mat plants such as turfs for rooftop greening. SOLUTION: The ground weight-reducing member for mat plants is structured by integrally forming a plurality of volume-up parts separated from one another, and groove parts formed around the periphery of the bottoms of the volume-up parts: wherein any of uppermost points of the volume-up parts are positioned within 12 cm in their shortest distance to the points from either of the groove parts, and the height of each of the volume-up parts corresponds to≥3 cm. COPYRIGHT: (C)2009,JPO&INPIT
