Natural Regeneration in a Multi-Layered Pinus sylvestris-Picea abies Forest after Target Diameter Harvest and Soil Scarification

Abstract

Forest management in Sweden can be characterized by even-aged silviculture heavily relying on three established harvest regimes: clearcutting, the seed-tree method, and the shelterwood system. Less intense, small-scale retention harvest systems such as single tree and group selection harvest are rarely used. In addition, natural regeneration dynamics without enrichment planting have barely been studied. Consequently, this study examined natural regeneration establishment in a multi-layered Pinus sylvestris-Picea abies forest stand in southwest Sweden after target diameter harvesting and soil scarification. The creation of forest canopy gaps had a positive effect on total seedling density five years after harvest, mainly due to a significantly higher number of Betula pendula individuals. Seedling density of more desirable tree species suitable for continuous cover forestry such as Fagus sylvatica, Quercus petraea and Picea abies also increased substantially in gaps when compared to pre-harvest conditions or the unharvested plots. In contrast, soil scarification did not increase the number of seedlings of desired tree species due to a significant decrease in Picea abies abundance. Soil moisture and gap size significantly improved Betula pendula seedling establishment while a larger number of Quercus petraea seedlings were observed in Vaccinium myrtillus patches. We conclude that canopy gaps are beneficial under the encountered stand conditions to initiate forest regeneration, and that soil scarification without the timely occurrence of a mast year of desired tree species is not effective in the type of forest studied.

Effects of Stand Features and Soil Enzyme Activity on Spontaneous Pedunculate Oak Regeneration in Scots Pine Dominated Stands – Implication for Forest Management

“…We found that the cover of bilberry negatively in uenced the establishment of oak seedlings. However, Drössler et al, (2017) observed more oaks in blueberry patches and suggested that the Eurasian jay (Garrulus glandarius) prefers to hide acorns under dwarf shrub vegetation. A negative impact on oak seedlings was observed from fern cover.…”

Strip Clear-Cutting Application and Logging Typologies for Renaturalization of Pine Afforestation—A Case Study

“…The modern silvicultural approaches lead to aggregated retention, which is the practice of leaving unlogged patches within logged areas, and is a form of retention forestry that has gained increasing use globally as an alternative to clear-cut logging [33][34][35]. In contrast to clear-cutting, retention forestry maintains habitats for species affiliated with a closed forest-thus mitigating the negative effects of timber harvest-while also providing a habitat for early seral species [36,37]. These approaches are characterized by a set of fundamental principles, including an avoidance of clear-cutting, an emphasis on structural diversity and small-scale variability, the deployment of mixed species with natural regeneration, and an avoidance of intensive site-preparation methods [38].…”

Physical Properties of Seeds of Eleven Spruce Species

“…Approximately 40 spruce species have been identified to date, and all of them reside in the northern hemisphere [1,[3][4][5][6][7]. Spruces are the predominant tree species in extensive boreal forests [8][9][10][11][12]. They have higher soil requirements than pines, and they thrive on brown sandy loam and loamy sand soils [7,13].…”