Application of Mg-fertilizers to prevent and to decrease Norway spruce yellowing

Abstract

Yellowing of the Norway spruce is a relatively common problem in many areas of the Czech Republic. In some of them, it is also connected with forest decline; it was studied in the Šumava (Bohemian Forest) Mts. and in the western part of the Krušné hory Mts. This unfavourable phenomenon is initiated by several ecological as well as anthropic processes, one of the most important being the imbalance of forest stand nutrition. Particular reasons lead to the deficiency of nutrients, especially of magnesium. Solution of this undesirable trend is the profound ecological analysis and cause-oriented treatments. Besides lowering the air pollutant input, fertilization with deficient nutrients is a successful treatment in the forest stand management in affected areas. In the areas of interest, the application of a relatively small amount of appropriate fertilizer (SILVAMIX Mg) led to considerable improvement in the defoliation dynamics and yellowing progress since the first years after use.