Forest stands near the timberline naturally create cluster structure. Information about cluster arrangements of groups was used by afforestation on unfavourable localities in the mountains. Norway spruce was planted in small collectives on plot Růžová hora Mt. in the Krkonoše Mts. in 1993. Dwarf pine was planted among groups. Spruce in groups is higher compared with individuals growing lonely. Differences in heights are also in groups, trees in central parts are higher than marginal trees. Individuals in groups improve microclimatic conditions in groups. Natural regeneration of spruce and other species occurs on the plot. Next amalgamations of groups bring the need of thinnings to prevent the formation of uniform thickets.
Skupinovitá obnova porostu při horní hranici lesa. [Cluster stand regeneration in the upper timberline] 1 - 4.