Whenever natural regeneration is not possible or successful, we usually resort to artificial regeneration with planting. Due to high planting costs, low-density planting is used in practice, however, this does not always ensure the desired quality of the trunk. In this study, we have analysed the growth and quality parameters of the crop pedunculate oak trees, which were measured in 2011 and 2020, from four naturally and six artificially regenerated stands in the three largest forest complexes of lowland pedunculate oak forests in Prekmurje (Hraščica, Ginjevec and Črni log). The crop pedunculate oak trees from naturally established stands have reached a statistically significant lower diameter at breast height and height as well as a higher H/D ratio than those crop trees from the artificially established stands. Most signs of future commercial quality have indicated a more favourable development of the crop trees from naturally regenerated stands. In these, we detected an average of 50 high-quality crop trees/ha, and in artificially regenerated stands, on average, half less. Planting density and the density of naturally seedlings as well as cover of the tree and shrub layer have proven to have the strongest positive affect on the quality of the crop trees. In the artificially regenerated stands, we have observed a significantly better quality structure in stands with higher planting density (above 5000/ha) than in stands with lower planting density (under 5000/ha). For this reason, we recommend trying lower-density planting in the form of group planting that has shown promising results in some studies.
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