ZLV Online

Abstrakt

Spruce decline is one of the most pressing tasks in some parts of northern Moravia and Silesia (Czech Republic). The main reasons are probably unsatisfactory state of forest soils due to former pollution deposition, precipitation deficiency and high temperature in vegetation seasons connected with global climate change. Honey fungus and bark beetle attacks should be considered as accompanying factors. Nowadays, thinning strategy in the affected area is questioned. Observational studies began in young spruce stands from natural regeneration in order to determine their structure and health status. Ten spruce thickets were selected in 2015. In seven stands, first precommercial thinning was already done in 2010–2013, three stands remain unthinned. Share of Norway spruce in the investigated thickets is generally high (65–98%). Although share of spruce affected by yellowing is quite high (25–64%), numbers of unaffected trees are still sufficient and the stands are capable of fulfilling all desirable forest functions. Our study brings no evidence of catastrophic disintegration of young spruce stands after thinning, and thus we consider thinning as an appropriate measure even in the areas affected by Norway spruce decline.