scholarly journals Variability in density of spruce (Picea abies [L.] Karst.) wood with the presence of reaction wood

2008 ◽  
Vol 53 (No. 3) ◽  
pp. 129-137 ◽  
Author(s):  
V. Gryc ◽  
P. Horáček
Keyword(s):  
Picea Abies ◽  
Moisture Content ◽  
Wood Density ◽  
Compression Wood ◽  
Wood Properties ◽  
3D Models ◽  
Reaction Wood ◽  
Stem Height ◽  
Sample Tree

The study was aimed to assess the integral value that determines wood properties − wood density at a moisture content of 0% and 12%. The wood density was researched in a sample tree with the presence of reaction compression wood. The density was determined for individual zones (CW, OW, SWL and SWR). The zone where compression wood (CW) is present has a higher density than the remaining zones. On the basis of the acquired data, 3D models were created for individual zones; they describe the variability of wood density along the stem radius and stem height. The influence of the radius seems to be a statistically highly significant factor. The wood density is significantly higher in samples with the presence of compression wood. When the proportion of compression wood in the sample was 80%, the wood density was 1.5 times higher compared to wood without compression wood.

scholarly journals Variability of spruce (Picea abies [L.] Karst.) compression strength with present reaction wood

2009 ◽  
Vol 55 (No. 9) ◽  
pp. 415-422 ◽  
Author(s):  
V. Gryc ◽  
H. Vavrčík
Keyword(s):  
Picea Abies ◽  
Compression Strength ◽  
Compression Wood ◽  
3D Models ◽  
Reaction Wood ◽  
Stem Height ◽  
Direction Parallel ◽  
Strength Limit ◽  
Wood Compression ◽  
Wood Strength

The aim of research was to find out the variability of spruce (<I>Picea abies</I> [L.]) Karst.) wood compression strength limits in the direction parallel to grain. The wood strength was examined using samples from a tree with present reaction (compression) wood. The strength was found out for individual stem zones (CW, OW, SWL and SWR). The zone with present compression wood (CW) demonstrated slightly higher values of wood strength limits. The differences in the limits of compression strength parallel to grain in individual zones were not statistically significant. All the data acquired by measuring were used to create 3D models for each zone. The models describe the strength along the radius and along the stem height. The change of strength along the stem radius was statistically highly significant. There was an obvious tendency towards an increase in the strength limit in the first 40 years. With the increased stem height, there is a slight decrease in wood strength.

scholarly journals The variability of wood density and compression strength of Norway spruce (Picea abies/L./Karst.) within the stem

Beskydy ◽  
2017 ◽  
Vol 10 (1-2) ◽  
pp. 17-26 ◽  
Author(s):  
Petr Horáček ◽  
Marek Fajstavr ◽  
Marko Stojanović
Keyword(s):  
Picea Abies ◽  
Wood Density ◽  
Compression Strength ◽  
Wood Properties ◽  
Stem Height ◽  
The North ◽  
Sample Tree ◽  
Wood Compression ◽  
Increasing Trend ◽  
Wood Strength

This study relates to the variability of wood density and compression strength parallel to grain within the stem of spruce trees (Picea abies/L./Karst.). The sample tree originated from the Giant Mountains and was an adult autochtonous mountain spruce. The properties were analysed for wood that formed between 1850 and 1990 along (1) the north-south oriented radius and along (2) the stem height on test specimens with the following dimensions: 20×20×30 mm, prepared from logs taken from the stem base at distances of 2, 4, 6, 10, 14, 20, 22, 24 and 26 m. In individual sections, the properties of the samples oriented in the north or south direction did not differ, while the effect of different ages on the properties showed statistically significant differences at each orientation (p < 0.05). Along the radius, the properties showed an increasing trend in tree-rings that developed between 1850 and 1940 with a slight decrease in the following years. The coefficient of variation in various decades was 1–7 % (wood density) and 3–15 % (wood compression strength). Along the stem height, the properties gradually increased to a height of 20 m, while the increase in values ​​was more pronounced in the 22–26 m interval. The variability of the wood properties along the stem height corresponded to the variability of the properties along the stem radius. A linear dependence between wood strength and density was demonstrated. Compared to what had been previously written, wood density showed a greater impact, probably due to the biomechanical optimization of the stem with regard to mechanical wind and snow loads in the mountains.

scholarly journals Resin canals in spruce (Picea abis /L./ Karst.) with the occurrence of reaction wood

2005 ◽  
Vol 53 (1) ◽  
pp. 85-92 ◽  
Author(s):  
Vladimír Gryc ◽  
Petr Horáček
Keyword(s):  
Compression Wood ◽  
3D Models ◽  
Resin Canal ◽  
The Other ◽  
Stem Length ◽  
Reaction Wood ◽  
Spruce Wood ◽  
Other Hand ◽  
Resin Canals

The paper was aimed at the determination of variability of horizontal resin canal dimension in spruce wood in relation to the position in a spruce stem. Significant changes of dimensions in horizontal resin canal along the stem length and radius were found. On the basis obtained of results 3D models (for CW, OW, SWL and SWP zones) describing changes in resin canal dimensions in spruce in relation to the position in a stem were created. In the models, the resin canal dimension decreases with the height of a stem and on the other hand, with an increasing distance from the stem pith the dimension of resin canal increases. The importance of the paper consists in the enlargement of findings about the structure of spruce with compression wood.

Mechanical Characteristics of Historical Beams of Picea Abies Wood: Assessment by Ultrasound

2014 ◽  
Vol 1618 ◽  
pp. 257-262
Author(s):  
Javier Ramón Sotomayor-Castellanos ◽  
José María Villaseñor-Aguilar
Keyword(s):  
Picea Abies ◽  
Moisture Content ◽  
Wood Density ◽  
Modulus Of Elasticity ◽  
Mechanical Characteristics ◽  
Structural Members ◽  
Full Size ◽  
Ultrasound Waves ◽  
Ultrasound Measurements ◽  
Speed Of Ultrasound

ABSTRACTFive historical full-size wood structural beams of Picea abies were tested with ultrasound. The speed of ultrasound, the modulus of elasticity, the moisture content and the wood density were measured for each specimen. The speed of the ultrasound waves in the radial, tangential and longitudinal directions was 1,769 m/s, 1,599 and 5,713 m/s respectively. The modulus of elasticity in the radial, tangential and longitudinal directions was 1,353 MPa, 1,069 MPa and 13,863 MPa respectively. The moisture content was on average 11.92% and the density was on average 422 kg/m3. Wood parameters such as density and orthotropic directions had influence in ultrasound measurements. In spite of local weakness in the beams, they had enough strength to be considered full structural members.

scholarly journals Identification of Molecular Markers for Selected Wood Properties of Norway Spruce Picea abies L. (Karst.) I. Wood Density

2004 ◽  
Vol 53 (1-6) ◽  
pp. 45-50 ◽  
Author(s):  
T. Markussen ◽  
A. Tusch ◽  
B. R. Stephan ◽  
M. Fladung
Keyword(s):  
Picea Abies ◽  
Norway Spruce ◽  
Wood Density ◽  
Wood Properties ◽  
Scar Markers ◽  
Exact Test ◽  
Monomorphic Band ◽  
Subsequent Conversion ◽  
Sib Families ◽  
First Time

AbstractThe identification of AFLP markers and their subsequent conversion to SCAR-markers linked to wood density of Norway Spruce (Picea abies L [Karst.]) is described for the first time. In AFLP-analyses, 102 different primer enzyme combinations were screened in a bulked segregant approach comparing individuals with high and low wood density. A total of 107 polymorphic AFLP fragments were obtained between the DNA-pools. Twenty-three markers were selected for further analyses to verify their linkage to wood density based on individuals used for pool constitution and additional unrelated clonal material. For 15 markers, a significant linkage to wood density was confirmed by a two-sided Fisher’s-exact test. Four markers were converted into SCAR markers and validated for plant material assayed for wood density by X-ray microdensitometry. For each marker a monomorphic band was obtained using sets of nested primers or restriction site-specific primers (RSS), which include the AFLP-restriction recognition sites. For two markers that are linked to high wood density, a separation from unlinked size homologous marker-alleles was realized by a PCR-restriction approach. Validation of these markers in different full-sib families confirmed their usability to separate the classes for low and high wood density of Picea abies.

Air permeability in longitudinal and radial directions of compression wood of Picea abies L. and tension wood of Fagus sylvatica L.

Holzforschung ◽  
2009 ◽  
Vol 63 (3) ◽  
Author(s):  
Asghar Tarmian ◽  
Patrick Perré
Keyword(s):  
Picea Abies ◽  
Fagus Sylvatica ◽  
Tension Wood ◽  
Compression Wood ◽  
Air Permeability ◽  
Normal Wood ◽  
Reaction Wood ◽  
Anatomical Point ◽  
Bordered Pits ◽  
The Difference

Abstract The air permeability in longitudinal and radial directions of compression wood in spruce (Picea abies) and tension wood in beech (Fagus sylvatica) was compared with that of the corresponding normal wood. The primary aim of the present study was to explain why the reaction woods dry more slowly than the normal woods in the domain of free water. A number of boards conventionally dried to an average final moisture content of 12% were chosen to perform the measurements. Bordered pits on the radial walls of longitudinal tracheids in the compression and normal wood and intervessel or intervascular pits in the tension and normal wood were also examined. The reaction wood of both species is less permeable than the normal wood, both in longitudinal and radial directions. The difference in permeability was more pronounced between compression and normal wood of spruce, especially in longitudinal direction. From an anatomical point of view, this is likely related to some differences in anatomical characteristics affecting the airflow paths, such as the pit features. Such results can explain the difference in drying kinetics of the reaction and normal woods in the capillary regime of drying.

Susceptibility of pretreated wood sections of Norway spruce (Picea abies) clones to enzymatic hydrolysis

2012 ◽  
Vol 42 (1) ◽  
pp. 38-46 ◽  
Author(s):  
Yohama Puentes Rodriguez ◽  
Helena Puhakka-Tarvainen ◽  
Ossi Pastinen ◽  
Matti Siika-aho ◽  
Leila Alvila ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Picea Abies ◽  
Norway Spruce ◽  
Wood Density ◽  
Lignin Content ◽  
Trichoderma Viride ◽  
Wood Decay ◽  
Wood Properties ◽  
Acid Pretreatment ◽  
The Relationship

The structure of softwoods, which confers resistance to degradation through hydrolysis and decay, currently limits their use for the production of biofuels. However, since wood is very heterogeneous, it is possible that differences in wood properties within and between trees could differentially affect its processability. In this research, heartwood (inner) and sapwood (outer) from Norway spruce ( Picea abies (L.) Karst.) clones were enzymatically hydrolyzed by Trichoderma viride cellulases after concentrated acid pretreatment. Wood sections with two particle sizes were compared based on their susceptibility to enzymatic hydrolysis, evaluated by assaying the formation of hydrolysis products and measured as reducing sugar yield (RSY). We also studied the relationship between RSY and the susceptibility to Heterobasidion parviporum wood decay and whether these traits are reflected in wood density and yield. Wood from the outer section produced more RSY with higher glucan but lower lignin content than wood from the inner section. Furthermore, susceptibility to enzymatic hydrolysis was positively correlated with H. parviporum wood decay, while both processes were negatively correlated with wood density. Our results revealed the importance of clonal trials for identifying suitable lignocellulosic biomass when considering wood properties and indicate that potential genotypes for the production of biofuels are not necessarily the most productive.

Effects of release from suppression on wood functional characteristics in young Douglas-fir and western hemlock

2006 ◽  
Vol 36 (8) ◽  
pp. 2038-2046 ◽  
Author(s):  
Heidi J Renninger ◽  
Barbara L Gartner ◽  
Frederick C Meinzer
Keyword(s):  
Moisture Content ◽  
Wood Density ◽  
Growth Ring ◽  
Specific Conductivity ◽  
Ring Width ◽  
Wood Properties ◽  
Tsuga Heterophylla ◽  
Douglas Fir ◽  
Western Hemlock ◽  
Growth Ring Width

Little is known of wood properties in trees that were initially suppressed and subsequently released from suppression. The purpose of this study was to assess differences in growth ring width, specific conductivity (Ks), tracheid dimensions, moisture content, and wood density in suppressed Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and western hemlock (Tsuga heterophylla (Raf.) Sarg.) trees and trees released from suppression averaging 12–18 years of age. Growth ring width was 370% higher for Douglas-fir and 300% higher for western hemlock trees released from suppression, and Ks was 182% higher for Douglas-fir and 42% higher for western hemlock trees released from suppression. Earlywood width was approximately four times greater after release in both species, whereas the relative increase in latewood width was much greater in Douglas-fir. Tracheids were 25% wider and 11% longer in released Douglas-fir trees. In western hemlock, released trees had 19% wider tracheids that were approximately the same length as those in suppressed trees. Moisture content was 66% greater in released Douglas-fir and 41% greater in released western hemlock. Wood density decreased by 21% in Douglas-fir trees and by 11% in western hemlock trees released from suppression. However, wood density of released trees did not differ from average reported values, implying that wood from released trees may be suitable for many of its traditional applications.

scholarly journals Effect of Stem Diameter, Genetics, and Wood Properties on Stem Cracking in Norway Spruce

Forests ◽  
2018 ◽  
Vol 9 (9) ◽  
pp. 546 ◽  
Author(s):  
Pauls Zeltiņš ◽  
Juris Katrevičs ◽  
Arnis Gailis ◽  
Tiit Maaten ◽  
Endijs Bāders ◽  
...  
Keyword(s):  
Picea Abies ◽  
Norway Spruce ◽  
Tree Ring ◽  
Wood Density ◽  
Wood Properties ◽  
Provenance Trial ◽  
Breast Height ◽  
Silvicultural Treatments ◽  
Latewood Density ◽  
Potential Risks

The choice of seed material (genetics) is one of the tools that can improve adaptation to the changing climate. Insufficient adaptation can result in a number of potential risks, including stem cracking. The goal of this study is to assess the influence of genetics and wood properties on stem cracking in Norway spruce (Picea abies Karst). The study was conducted on a 35-year-old provenance trial in Eastern Latvia. Stem cracks were assessed using a six-score scale. Tree-ring parameters, i.e., latewood proportion, maximum and mean density, mean earlywood, and latewood density were analysed. The overall incidence of stem cracking was 23.5%, varying between 0% and 79% at a family mean level. Heritability of stem cracking was low, ca., two times lower than for the diameter at breast height (DBH): h2 = 0.09 and 0.21, respectively. There were non-significant family and provenance effects on the occurrence of stem cracks, and weak family mean correlations between DBH, and the proportion of trees with any stem cracks or severe stem cracks. Overall, larger trees were more prone to cracking irrespective of provenance or family. Cracked trees had lower wood density parameters than unaffected trees, yet the latewood proportion was similar. Silvicultural treatments or selection to improve wood density could be suggested to reduce the risk of stem cracking.

Sign in / Sign up

Export Citation Format

Share Document