The data from the old management plans and the last two inventories on the permanent sampling plots (PSP, n = 247) were used to analyze changes in growing stock and diameter structure of the silver fir in the Bohor forests (Forest Management Region Brežice, Forest Management Unit (FMU) Bohor) where beech forests on acid and carbonate bedrock prevail. Additionally, field surveys of regeneration on the location of 51 PSP were made in the central part of the FMU Bohor (1.5*3.25 square kilometers) in order to analyze tree species composition, height structure, and browsing damages of regeneration. Ashare of silver fir in total growing stock has been changing during the analyzed period 1958-2008; in the last thirty years the share of silver fir in total growing stock has increased from 10.4 % to 14.1 %. Even more striking is an increasing share of silver fir in small diameter trees with diameter at breast height 10-30 centimeter, which has increased by 6 percentage points in the period 1987-2007. Silver fir regeneration is abundant (25.1 % of total number of saplings) and the ingrowth of fir saplings in higher height classes is successful. The progression of the silver fir in the Bohor forests is an exception in Slovenia; therefore a more detailed research of causes for successful silver fir development is worth making. Possible reasons could be low density of red deer, site conditions, and management treatments.
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