Control of soil fertility – substratum in forest nurseries “Stanovi” and “Usora” in Doboj

Abstract

Control of soil fertility - substratum in forest nursery Stanovi – Doboj was performed in year 1984, 1986, 1988, 1991 and 2000. These examinations involved the state of soil acidity, humus content and accessible phosphorus and potassium content. Based on performed chemical analyses, recommendations were given for the selection of type of fertilizer, quantity and time of putting in the fertilizer. During September 2006, soil – substratum samples and spruce seedlings were taken from nurseries “Stanovi” and “Usora” and basic chemical analyses were conducted. Based on the results, the conclusion is following – realization, in other words, application of former recommendations for fertilizing was performed partially and selectively, in such a way that after each control the connection in nutriments content was changed on every parcel. Content of humus, nitrogen, phosphorus and potassium was considerably reduced in war and post-war period, because of the reduction of fertilizer use. Nowadays, accessible potassium contents are in middle supply limits, and accessible phosphorus content is in low supply limits, so phosphorus fertilization is necessary in every case. For further use it is recommended to use pure phosphorus fertelizers, or in lack of this, mixture fertilizes with much more phosphorus than potassium content.