Tree- and Stand-Level Thinning Effects on Growth of European Beech (Fagus sylvatica L.) on a Northeast- and a Southwest-Facing Slope in Southwest Germany

Abstract

Anticipated changes in climate and research findings on the drought sensitivity of beech have triggered controversial discussions about the future of European beech. We investigated the growth response of beech on the tree-and stand-level in mature stands to three different thinning intensities (no thinning, strong thinning, very strong thinning) on a northeast-and southwest-facing slope in Southwest Germany. Linear mixed-effects models were formulated to describe effects on growth parameters on the tree-and stand-level (diameter, height, basal area, volume). At the stand-level, the stand basal area increment and stand volume increment were lower on the thinned plots. At the tree-level, the basal area increment significantly increased with increasing thinning intensity. The growth of individual trees was also influenced by initial tree size, the size-related rank of the tree within a stand, and by the aspect of the site. Our data indicate that growth of European beech is impaired on the southwest-facing slope with a warmer and drier climate and that a very strong thinning regime applied at advanced age can accelerate growth of European beech trees even on the warmer and drier site. Our findings, therefore, imply that in a warmer climate intensive thinning may also represent an important adaptive forest management measure in European beech stands. OPEN ACCESSForests 2015, 6 3257

Variability of European beech wood density as influenced by interactions between tree-ring growth and aspect

“…It is well known that different silvicultural treatments such as thinning increase radial growth. This has been shown also for European beech (Boncina et al 2007;Ottorini 1993, 1999;van der Maaten 2012;Diaconu et al 2015). In this context our results reveal that thinning might not only give higher radial growth rates but also higher wood density.…”

Major Changes in Growth Rate and Growth Variability of Beech (Fagus sylvatica L.) Related to Soil Alteration and Climate Change in Belgium

“…Yet, it is unlikely that the decrease of beech growth rate is related to thinning practices. Indeed, higher thinning intensity is rather known to increase the growth rate and the resilience to climate of mature beech trees [60][61][62]. The widespread use of harvesting machines in Belgium is more likely responsible for the alteration of the soil ecology, with adverse consequences on tree growth [9].…”

A comparison of different tending variants in beech stands by the crown thinning and from the view of their quantitative and qualitative development

“…The results of many authors (Hein et al 2007;Boncina et al 2007;Štefančík 2015) confirmed that crown level thinning with positive selection are the most appropriate methods especially for growing of selective quality stands. The method of candidates (Schädelin 1934;Leibundgut 1966;Réh 2004), promising trees (Štefančík 1984) or target trees (Boncina et al 2007;Diaconu et al 2015;Štefančík 2015) is preferred. Advantages of the target trees method were also confirmed by Hein et al (2007), who based on a 35-year research found a higher stem quality and/or net value production on plots with thinnings and selected target trees in comparison with plots where interventions according to Assmann´s optimal basal area were performed.…”

“…Among these, different variants of low thinning (Foerster 1993;*Corresponding author. Igor Štefančík, e-mail: stefancik@nlcsk.org, phone: +421 45 5314 234 Utschig & Küsters 2003) and also crown thinning (Assmann 1968;Šebík & Polák, 1990;Hoffmann 1994;Štefančík et al 1996;Pretzsch 2005), both on the single tree or stand level (Diaconu et al 2015), were observed and compared mutually.…”

“…Although a number of site, natural and environmental factors (Vacek et al 1996;Vacek & Hejcman 2012;Vacek et al 2014), and genetic properties and traits (Ducros et al 1988;Hansen et al 2003;Gömöry & Paule 2011;Gömöry et al 2013) affect the growth and development of beech stands, the methods of their management (Poleno & Vacek et al 2009), or the methods of their tending represented by the type and intensity of tending interventions (Assmann 1968;Šebík 1971;Štefančík 1974;LeGoff & Ottorini 1993;Dhôte 1997;Utschig 2000;Pretzsch 2005;Tufekcioglu et al 2005;Saje et al 2013;Diaconu et al 2015) remain one of the most important factors.…”