On some locations in Slovenia within the same sites, some silver fir trees (Abies alba MilI.) remain healthy while others decline or die. Since 1988 more than 400 adult, dominant or codominant trees from two typical Dinaric silver fir-beech forest stands have been observed. The phenological characteristics, occurrence of epicormic branches and abundance of male and female cones were assessed and related to tree health. Among five phases of shoot growth, the time of bud bursting proved to be the most significantly correlated to tree condition. Declining trees generally flushed at least one week earlier than non-affected ones. Secondary crown, when present, was always associated with tree decline, but no correlation was found between its presence and the time of bud bursting. The frequency of male and especially of female cones decreased with increasing tree damage. It remains to be studied whether the earlier flushing is an inherited characteristic or a consequence of tree damage.
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