Translations:Manfred Klett: Von der Agrartechnologie zur Landbaukunst/995/en

Rock dusts divide into those derived from sedimentary rocks and those derived from silicates. In the sediments — less in the clay-shales than rather in soils on pure limestone, e.g. Upper Jurassic, or on quartz sandstones and quartzites — considerable substance deficiencies are to be found. In both cases the soils are only limitedly capable of development. On the alkaline side, phosphorus deficiency occurs; on the acid side, calcium, magnesium and potassium are lacking. Only the equilibration between the two extremes ensures a healthy humification and soil development overall. Where the aim is to lower the degree of acidity — that is, to raise the pH value towards 6 to 7 — lime dusts (CaCO₃) as a substitute for classical marling are the appropriate means. Finely ground, they act immediately. To avoid potassium losses through exchange processes, the required quantity should be distributed over several years in moderate doses. Coarser granulations up to lime grit ensure a lasting, soil-building efficacy. A special form is the use of burnt lime (CaO). It is highly active, but gradually converts in contact with soil moisture

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