Presentation summarises the evaluation of health status dynamics of allochthonous spruce stands on the Modrava Forest District and of natural stands on the Plešný Forest District. Analysis is based on dendroecological reactions of particular tree individuals in the stand texture. The tree damage was evaluated annually (during the period 1997 - 2002), based especially on the defoliation. The most tolerant appeared the natural and seminatural, especially mixed forest stands with dominant beech on the Plešný Forest District territory, the lowest one the allochthonous secondary spruce stands on the Modrava Forest District area. The damage dynamics was limited by the insect (bark beetle - Ips typographus) pest activity. Ozone damage appeared in 2002 much more often, compared to the 1999 year. The most damaged species were sycamore and rowan tree.
Key words: health status, defoliation, air-pollution and ecological stress, Ips typographus, ozone, transition matrix modelling