Author(s):
1. Vladimir Novotny, Croatian Forest Research Institute, Croatia
2. Mladen Ivanković, Croatian Forest Research Institute, Croatia
3. Saša Bogdan, Faculty of Forestry, Zagreb, Croatia
4. Miran Lanšćak, Croatian Forest Research Institute, Croatia
5. Sandra Crnković, Croatian Forest Research Institute, Croatia
6. Vlatko Uzelac, Croatian forests, limited liability company, Croatia

Abstract:
The absence of crop is one of the most current problems of forestry profession because the absence of spontaneous and periodic crops in nature causes natural regeneration becoming more and more questionable. In traditional forestry, seeds are produced in forest seed stands, which are spatially defined, phenotypically higher quality and more than 80 years old. This paper represents the initial phase of a longer time cycle of multidisciplinary research why, when and how, from young regular forest stand, grows seed stand. Main goals are:  Selection of species and establishment of permanent experimental plots for research  Determine and analyse the structural elements of permanent experimental plots  Determine the criteria for selection of seed trees  Determine the criteria for the implementation of breeding and genetic meliorative procedures Based on the scientific, professional and practical knowledge of forest management, silviculture, genetics and seed production, for the establishment of the plots, stands of pedunculated oak from second, third and fourth age class were chosen. Experimental plots are permanently marked, each consisting of four equal subplots of 0.25 ha, bounded on all sides by a 15-meter boundary zone. Each tree is marked by a number and a georeferenced. Statistical analyses of the stand structures and the structure of the crown of the experimental plots were based on the data of the terrain survey at the level of the tree, the level of the subplots and the level of the plots. Criteria for selecting seed trees was determined based on the model of phenotypic selection made by defining the objective criteria for evaluating the tree form, the quality of the crown, the fullness, the spiral grain, the position in the stand and the health status of all the oak trees. All oaks whose estimation of phenotype is greater than the minimum for one standard deviation of the total grade of the subplots phenotype, represent selected seed trees. Silviculture and genetic meliorative interventions, around selected seed trees, remove oak trees with their crowns touching or at a distance of up to 50 cm from their crowns and all other species of trees, whose height is greater than 2/3 of the height of the beginning of the crown of the selected tree.

Key words:
Seed crop,stand renewal,seed stand,seed tree,phenotypic selection,pedunculate oak

Thematic field:
Forest genetics, Forest seed science and nursery, afforestation

Date of abstract submission:
08.09.2017.

Conference:
Šumarska nauka u funkciji održivog razvoja šumarstva
25 godina šumarstva Republike Srpske