The aim of the survey was to examine various environmental factors that affect the rejuvenation of oak in the Karst region. Three sections with multiple harvesting treatments under transmission line Divača-Redipuglia were selected. In total 120 sample plots (4 m x 4 m) were placed. The plots were divided into three strata (middle open section, edge and under canopy of blackpine stand). Sections were selected according to the time of the last intervention. No differences in ecological conditions between sections were observed, the differences were only significant between the strata. Coverage of ground vegetation, shrub and tree layer was different between strata and sections. Coverage of ground vegetation was highest in the middle sections. Twelve shrub species were inventoried, the most common were smoke tree, privet and blackberry. Coverage of shrubs was highest in the middle section. A total of 12 tree species were registered, the most numerous were manna ash, oak and hop hornbeam. Increasing proportion of shrub and ground vegetation was negatively correlated to density of tree species. Number and coverage of the main tree species was the highest in section with the oldest intervention. Height of dominant individuals was significantly different between sections. The relative annual height increment was highest in the middle open section. On average, the relative height increment of previous year was larger.Vertical structure of regeneration showed the largest number of oak and manna ash in the class up to 50 cm and hop hornbeam in the class up to 300 cm. Average openness in the stand was 20 %. The proportion of browsed specimens of oak and hop hornbeam was the highest under the canopy, while this was the case for manna ash in the middle open section.
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