LAUSR

The paper summarises an evaluation of the health status dynamics of allochthonous spruce stands in the Modrava Forest District and of natural stands in the Plesný Forest District. Analysis is based on dendroecological reactions of particular tree individuals in the stand structure. The tree damage was evaluated annually (during the period 1997-2002), based especially on de- foliation. Natural and semi-natural, especially mixed forest stands with dominant beech in the Plesný Forest District territory were most tolerant, allochthonous secondary spruce stands in the Modrava Forest District area were least tolerant. The damage dynamics was limited by the activity of insect pests (bark beetle - Ips typographus). Damage caused by ozone occurred much more often in 2002 compared to 1999. The most damaged species were sycamore and rowan tree.