A5049871862- Forest ecology and management
- Wood Treatment and Properties
- Tree Root and Stability Studies
- Forest Biomass Utilization and Management
- Remote Sensing and LiDAR Applications
- Forest Ecology and Biodiversity Studies
- Wood and Agarwood Research
- Image Processing and 3D Reconstruction
- Forest Management and Policy
- Environmental Impact and Sustainability
- Botany and Plant Ecology Studies
- Plant Water Relations and Carbon Dynamics
- Plant biochemistry and biosynthesis
- Lignin and Wood Chemistry
- Bioenergy crop production and management
- Industrial Vision Systems and Defect Detection
- Cellular and Composite Structures
- 3D Surveying and Cultural Heritage
- Forest Insect Ecology and Management
- Civil and Structural Engineering Research
- Materials Engineering and Processing
- Botanical Studies and Applications
- Engineering and Materials Science Studies
- Peatlands and Wetlands Ecology
- Aeolian processes and effects
Forstliche Versuchs- und Forschungsanstalt Baden-Württemberg
2007-2023
Nordwestdeutsche Forstliche Versuchsanstalt
2014-2023
Forest Research Institute
2023
Forest Research Institute
2009-2014
University of Freiburg
2000-2007
Forest Research
2006
Northern Research Station
2006
This paper reports on the effect of wind loading below damaging strength tree mechanical and physical properties. In a wind‐exposed Sitka spruce stand in western Scotland, 60 trees at four different levels exposure (10 m, 30 50 90 m from edge) were characterized for stem crown size shape properties, including structural Young's modulus ( E struct ), natural frequency, damping ratio. increased edge to mid‐forest, but with large inter‐tree variation. Swaying frequency ratio also distance edge....
To further understand the mechanics of trees under dynamic loads, we recorded damped oscillations a Douglas fir (Pseudotsuga menziesii) tree and its stem without branches. Eigenfrequencies branches were calculated compared to oscillation frequency intact tree. The term eigenfrequency is used here characterize resonance branch fixed at proximal end solid support. All large had nearly same as This property prerequisite for distribution mechanical energy between leads an enhanced efficiency...
The quantitative description of local buckling hollow plant stems requires the knowledge Young's modulus in longitudinal and tangential directions for different tissues which stem is composed. For thick–walled shear radial–tangential plane needed an advanced treatment process ovalization. primary causes failure can be predicted if critical compressive strains direction tensile are known. All these mechanical properties their variation along length measured Arundo donax .
Knowledge about the wood quality of standing trees is crucial in that it serves as an excellent means for nearly all stages wood-supply chain. Better information internal characteristics can be derived from outside appearance by establishing a correlation between bark stem and its quality. This paper presents approach where determination using terrestrial light detection ranging (LiDAR) system combined with logs X-ray computed tomography (CT). Results show high accuracy branch scar...
Tree and log diameters are usually measured outside bark, but inside-bark of greater economic interest often derived with local or regional bark thickness equations. To date, the influence measurement method, sampling design, sample size on equation accuracy precision has received limited attention. The objectives this study were to use an extensive dataset for Norway spruce (Picea abies (L.) Karst) in southwestern Germany (1) quantify measurements a Swedish gauge, (2) determine required...
Free oscillations of upright plants' stems, or in technical terms slender tapered rods with one end free, can be modelled by considering the equilibrium between bending moments and resulting from inertia. For stems apical loads negligible mass stem for finite but without top loading, analytical solutions differential equations appropriate boundary conditions are available a number cases. other cases approximations leading to an upper lower estimate frequency oscillation ω derived. limiting...
Abstract Key message The TreeTrace_spruce database contains images and measurements of 100 Norway spruce ( Picea abies (L.) H.Karst.) logs from Northeastern France, each about 4.5 m long. image includes RGB large small ends the hyperspectral computed tomography (CT) wood discs sampled at both log ends. were also fully X-ray scanned with a CT device for roundwoods their top surface was terrestrial LiDAR device. performed on include local density, growth ring widths pith location. This is...
Mechanical tests were conducted on structural timber from a 37-year-old Sitka spruce (Picea sitchensis (Bong.) Carr), progeny trial located in Kershope Forest, Cumbria, UK. Values of modulus rupture (MOR) and global elasticity (MOEG) bending density compared between cut four the eight different seed lots which made up experiment. Three these open-pollinated selected plus trees, while fourth consisted trees grown an unimproved collection imported Queen Charlotte Islands (QCI) British...
The forest sector is important for the German Federal State of Baden-Württemberg (BW) and Västerbotten (VB) County in Sweden. Their forestry wood chains (FWCs) are similar magnitude supply industries. This study provides a regional comparison performance FWCs from roundwood harvesting, including hauling, to mill gate concerning factors that impact sustainability assess different indicators alternative chains, particular fully mechanized motor-manual operations. harvest volumes but...
Wood, as a natural material, has favourable properties in both technical and aesthetic aspects. Due to its inherent variability, production of high-quality sawn timber demands adequate control log conversion, which is feasible with computed tomography (CT) scanning. Existing appearance grading rules for might not fully reflect people's visual perception wood surfaces, therefore, an alternative, more perception-oriented classification could be beneficial. An based on partial least squares...
The green oak building research project deals with small-diameter logs as sustainable construction material for timber truss structures.The basis structural use and design are the specific mechanical properties knowledge of performance influencing factors like wood defects, moisture content density distribution.In a first step, characterisation raw itself has been done by quality assessment, followed determination strength stiffness parameters input parametric process prototype proof...
Abstract Cracks in softwood are an important defect that reduces the quality of sawn timber for construction purposes. As with all other reducing features wood, it is significant interest to know about their number and position a log before sawing. On one hand, cracks relatively easy distinguish from wood by means computer tomographic (CT) scanning owing large differences density. The fact they tend be irregular very thin, however, complicates detection. This study describes method automated...
Abstract Roundwood scanners utilizing X-ray computed tomography (CT) provide the information required for individual log-sawing optimization. However, errors in automated detection of quality-relevant internal wood features sawing control may lead to improper log positioning at breakdown, impairing realization value recovery potential. It is thus interest have an estimation impact feature on performance A sensitivity analysis was conducted quantify effect knot a breakdown optimization by...
Abstract Owing to favorable wood properties and its resilience the effects of climate change, Douglas fir ( Pseudotsuga menziesii ) is a promising tree species in Central Europe. Its bark extractives could also serve as feedstock for production bio-based materials platform chemicals. In this study, sapwood, heartwood, knotwood firs originating from three differently aged stands south-west Germany were investigated. Two different extraction methods with organic solvents compared: mixture...
In Germany, only half of the annual increment oak stands is used.Especially small-diameter oaks are currently either not used or as firewood.This research project aims on making logs available structural timber members.For this purpose, mechanical properties and factors influencing them must be determined.In experimental program, (oven-dry) wood density, moisture content, internal external defects round geometry were measured by non-destructive destructive methods.Additionally, dynamic...