gravel gray basalt, coarse is used as drainage strips above the road in the notch of the highway. the stones can serve as a shelte

above alley arranged asphalt barriers basalt bollard can coarse ditch down drain drainage ecology field garden gravel gray highway insect insects lawn line lines lizard lizards metal new notch plastic rain refugium regular road rock rockery rubble serve shelte shelter side slope slow stone stones street striped strips trees trench used water white