1.3 Consideration of the Geological-Pedological Situation
Establishing of vegetation on raw soils poor in humus generally requires considerably higher efforts than seedings on topsoil. Mainly sites with low nutrients and often coarse soil texture, but also microbial sterility make establishing vegetation in such sites a challenge. If then problematic pH-values are added (extremely high values like e.g. with ashes, clinkers, building rubble, or extremely low values like with pyrite-containing tertiary sands) a complete measurement catalog of melioration measures is to be considered to allow the growth of a permanent and vital vegetation.
From the view of professional aspects, raw soils are to be preferred to topsoil coverings, as they show better medium and long-term results in what concerns erosion control, ecology and aesthetics. Topsoil coverings frequently result in strict separating layers between topsoil covers rich in nutrients and sterile deeper soils, which are not or only insuffienctly penetrated by the root system. This leads to an only flat root system causing high susceptibility to droughts as well as reduced slope reinforcement.