| − | Topsoil must be capable of sustaining vigorous plant growth and to be free fromsubsoil, roots,vegetation, debris, toxic materials and stone over 50 mm diameter. Specify that topsoilsample must be provided to the consultant for testingand analysis including herbicide oratrazine content.All topsoil supplied must conform to asample provided. Minimum topsoil depthis 150 mm for turf areas andranging to 1.25 m for perennials, shrubs and trees. | + | Topsoil must be capable of sustaining vigorous plant growth and be free from toxic material and roots, stones or debris over 50 mm in diameter. Specify that samples of topsoil from each source to be drawn upon be provided to the consultant for visual inspection, along with topsoil quality test results from an accredited soil testing laboratory, or a quality assurance certificate from the supplier. We recommend restoring a minimum topsoil depth of 200 mm for planting turf areas, and 400 mm for planting perennials, shrubs and trees. |