The bottom soil and top soil for digging holes should be stacked separately, and base fertilizer should be applied to the bottom and top soil or modified soil should be backfilled.
The bottom soil and surface soil of the excavation shall be stacked separately, the base fertilizer shall be applied at the bottom, and the topsoil or improved soil shall be backfilled.
The subsoil and topsoil of the hole should be stacked separately, and the bottom should be applied with base fertilizer and backfilled with topsoil or improved soil.