(1) Trees and bushes within the subgrade land shall be cut down or transplanted before construction. Trees felled shall be piled up outside the subgrade land and properly handled.(2) Garbage, organic residue and humus soil (100~300mm) on the surface of the original ground of the borrow pit, turf, roots and topsoil of crops within the scope of subgrade land shall be removed, and the planting topsoil shall be stored in a place designated by the supervisor for future use as planting soil. After the site is cleaned up, it shall be fully rolled before filling to make its compactness meet the specified requirements.(3) For highway embankments of Grade II or above or those with filling height less than 1m, all roots within the scope of subgrade foundation shall be removed and the pits shall be filled and tamped. For highway embankments with filling height greater than 1m below grade ii, roots can be reserved, but roots cannot be exposed to the ground. In addition, the pits and holes within the subgrade land shall be filled and tamped. The roots of trees within the borrow pit