Silver fir (Abies alba Mill.) trees in Slovenia have been dying over the past decade. The precise etiology of decline is not known but air pollution is considered to be part of the problem. Interestingly, within the same site, some mature trees remain healthy while others are declining or dying. In the present study the phenology of shoot growth, occurrence of epicormic branches (secondary crown) and reproductive growth (megastrobili and microstrobili) have been observed and their relation to tree decline evaluated.