PURPOSE: To maintain and control lawn land while limiting the use of agricultural chemical as much as possible by utilizing soil blended with an operation soil containing charcoal powder or coal powder for soil dressing and forming surface soil layer for vegetation having ≥ specific pressure.

CONSTITUTION: Soil blended with ≥5wt.% operation soil containing 10-50wt.% charcoal, coal powder or mixture thereof is used for soil dressing to form surface soil layer having ≥20cm thickness of layer. In the formation, when the amount of charcoal, etc., in the operation soil is <10wt.%, sufficient effects are not exhibited and necessity of exceeding ≥50wt.% is not recognized so that the amount of charcoal, etc., is kept in the range of 10-50wt.%. In lawn land prepared by this method, the number of living organisms in soil is small, especially larvae of May beetles and insect pests such as striped flea beetle, lady beetle, aphid, etc., hardly live and infestation of leaf-blight, snow blight and rust is not observed.