engleski

Is selection of pedunculate oak provenances crucial for artificial regeneration of forest stands?

Pedunculate oak (Quercus robur L.) is the most important tree species in Croatia from commercial viewpoint. Regeneration of p. oak forest stands is demanding with increasing number of challenges which add to the management complexity. The share of artificially regenerated oak stands is high (two thirds in seedlings production on the national scale) for which, selection of appropriate oak provenance could be important. If poorly chosen, direct consequences for forest management could result in low wood production, low vitality, financial losses and problems with regeneration. To address these challenges selection of appropriate p. oak provenance must meet not only current requirements of site conditions, but future conditions as well. In contrary, established forest stand will not have needed stability to reach the end of rotation. Thus, provenance tests provide necessary background for silvicultural decision making in terms of provenances’ growth, production, vitality and consequently nursery production plans. The aim of the research is to answer the question is there significant differences in tree height and diameter at breast height (DBH) between provenances and if so, to single out the best provenances which could be supported and the worse ones to be excluded from management. Research includes 16 provenances on the locality Gajno (trial plots in central Croatia). Provenances originate from natural distribution of p. oak in Croatia, from the most eastern edge (provenance Mitrovica, Serbia, just at border with Croatia) up to the most western distribution edge (provenance Motovun). Trial was established in four repetitions, with 16 different provenances in the spring of 1988. In the spring of 2021. all trees in the trial were measured (tree height with Haglöf/Vertex IV and DBH with calliper). Trees were carefully measured according to their unique number for the purposes of repeated measure in 2023 and calculation of height, diameter and volume increment. Data were analysed using Statistica soft. ANOVA showed significant differences among studied provenances. Data analysis revealed that selection of provenance must be based on scientific results since it has prominent role in growth and development of p. oak trees in the fourth decade of their development. These findings are strongly advised to be used for artificial regeneration of p. oak stands in Central Croatia as well as for planning of nursery production on the national scale.

Adaptation strategy, assisted gene migration, silvicultural interventions

nije evidentirano