A new method for vulnerability analysis of small xylem areas reveals that compression wood of Norway spruce has lower hydraulic safety than opposite wood

Abstract The aim of the present study was to determine the effect of a variety of abnormal fibres on the mechanical properties of paper made from Norway spruce, Picea abies (L.) Karst. Fibres representing abnormality were obtained from trees treated by irrigation and fertilisation. Moreover, fibres from compression wood and its accompanying opposite wood were isolated. The effect of dislocations on paper quality was studied on four mixtures (20, 40, 60 and 80% fibres with induced dislocations) of untreated/compressed fibres. Two more groups consisting of control untreated samples and samples with 100%-induced dislocations were also included in the test. The mechanical properties of the paper were tested and the results were compared to those of control samples. Abnormal fibres reduced the desired mechanical properties of the final paper concerning tensile strength, modulus of elasticity and tear-tensile index. Irrespective of the type of treatment, all morphological changes introduced in fibre cell walls appear to directly affect changes in the mechanical properties of the paper. Control samples had a tear index of 25 compared to 10 mN m2 g-1 of samples containing 100% dislocations. It is obvious that 20% of dislocations, an amount that is expected to be induced in pulp under mechanical processing and transport, will contribute to a decrease in tear index with an average of 3 mN m2 g-1, i.e., 10% of the total value.

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Inter-Tracheid and Cross-Field Pitting in Compression Wood and Opposite Wood of Norway Spruce (Picea abies L.)

Notulae Scientia Biologicae ◽

10.15835/nsb326059 ◽

2011 ◽

Vol 3 (2) ◽

pp. 145-151 ◽

Cited By ~ 4

Author(s):

Asghar TARMIAN ◽

Mohammad AZADFALLAH ◽

Hadi GHOLAMIYAN ◽

Mahdi SHAHVERDI

Keyword(s):

Picea Abies ◽

Norway Spruce ◽

Compression Wood ◽

Microfibril Angle ◽

Air Permeability ◽

Sem Images ◽

Aperture Diameter ◽

Opposite Wood ◽

Bordered Pits ◽

S2 Layer

Inter-tracheid and cross-filed pit specifications in compression wood and opposite wood of Norway spruce (Picea abies) were determined. Fewer pits of a smaller size and a smaller aperture diameter were observed in compression wood. In contrast to the uniseriate arrangement of bordered pit pairs in compression wood, both uniseriate and biseriate pits were observed in opposite wood. In contrast to the circular view of the pit aperture in opposite wood, a slit-like pit aperture was often observed in compression wood. SEM images showed a number of helical fissures on the tracheid walls and bordered pits of compression wood along the microfibril angle in the S2 layer. The cross-field pits in compression wood were dominantly piceoid but sometimes cupressoid and occasionally taxodioid, whereas they were mostly piceoid and occasionally cupressoid in opposite wood. Overall, some significant differences in the inter-tracheid and cross-field pitting between the compression wood and opposite wood can give some explanations for their different air permeability and drying kinetics found in the previous studies.

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Cross-field pitting characteristics of compression, lateral, and opposite wood in the stem wood of Ginkgo biloba and Pinus densiflora

IAWA Journal ◽

10.1163/22941932-00002107 ◽

2020 ◽

Vol 41 (1) ◽

pp. 48-60

Author(s):

Byantara Darsan Purusatama ◽

Nam Hun Kim

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Ginkgo Biloba ◽

Compression Wood ◽

Pinus Densiflora ◽

Reaction Wood ◽

Stem Wood ◽

Opposite Wood ◽

The Cross ◽

Scanning Electron

Abstract The characteristics of cross-field pitting among compression wood, lateral wood, and opposite wood, in the stem woods of Ginkgo biloba and Pinus densiflora were investigated with optical and scanning electron microscopy. In Ginkgo biloba, compression wood exhibited piceoid pits, while lateral and opposite wood exhibited cupressoid pits. The compression wood of Pinus densiflora exhibited cupressoid pits and piceoid pits, while lateral wood and opposite wood exhibited pinoid and window-like pits in the cross-field. In both species, compression wood yielded the smallest pit number among each part, while opposite wood yielded the greatest pit number per cross-field. Cross-field pitting diameters of compression wood and opposite wood were significantly smaller than lateral wood in Ginkgo biloba, while the cross-field pitting of compression wood was the smallest in Pinus densiflora. Radial tracheid diameter of compression wood was slightly smaller than lateral and opposite wood in Ginkgo biloba and significantly smaller than lateral and opposite wood in Pinus densiflora. In conclusion, the cross-field pitting type, pit number, and cross-field pitting diameter could be used to identify reaction wood in the stem wood of Ginkgo biloba and Pinus densiflora.

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MICROFIBRIL ANGLE OF THE S1 CELL WALL LAYER OF NORWAY SPRUCE COMPRESSION WOOD TRACHEIDS

IAWA Journal ◽

10.1163/22941932-90000374 ◽

2004 ◽

Vol 25 (4) ◽

pp. 415-423 ◽

Cited By ~ 11

Author(s):

Jonas Brändström

Keyword(s):

Norway Spruce ◽

Compression Wood ◽

Microfibril Angle ◽

Soft Rot ◽

Wall Layer ◽

Thermomechanical Pulp ◽

Ultrastructural Organization ◽

Normal Wood ◽

Cell Wall Layer ◽

Fracture Characteristics

The ultrastructural organization of the outer layer of the secondary wall (i.e. S1 layer) of Norway spruce (Picea abies (L.) Karst.) compression wood tracheids was investigated with emphasis on the microfibril angle. Light microscopy was used to study the orientation of soft rot cavities (viz. microfibril angle) in compression wood tracheids from macerated soft rot degraded wood blocks. In addition, surface and fracture characteristics of compression wood tracheids selected from a thermomechanical pulp were investigated using scanning electron microscopy (SEM). Results showed that the orientation of soft rot cavities varied little between tracheids and the angles were also consistent along the length of individual tracheids. The average S1 microfibril angle in two selected annual rings was 90.0° ± 2.7° and 88.9° ± 2.4° respectively. SEM observations of the compression wood tracheids from the pulp showed distinct fractures between S1 and S2 or within S1 and these fractures were oriented perpendicular to the tracheid axis. It was concluded that the microfibril angle of the S1 layer of compression wood tracheids is higher and less variable than normal wood tracheids. This is considered an adaptation for restraining the compressive forces that act on leaning conifer stems or branches.

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Strength and stiffness of the reaction wood in five Eucalyptus species

Holzforschung ◽

10.1515/hf-2018-0091 ◽

2019 ◽

Vol 73 (2) ◽

pp. 219-222

Author(s):

Bruno Charles Dias Soares ◽

José Tarcísio Lima ◽

Selma Lopes Goulart ◽

Claudineia Olímpia de Assis

Keyword(s):

Mechanical Behavior ◽

Tension Wood ◽

Compression Wood ◽

Vertical Position ◽

Eucalyptus Species ◽

Reaction Wood ◽

Opposite Wood ◽

Average Slope ◽

Strength And Stiffness

AbstractTree stems deviating from the vertical position react by the formation of tension wood (TW) or compression wood (CW), which are called in general as reaction wood (RW), in which the cells are modified chemically and anatomically. The focus of the present work is the mechanical behavior of TW in five 37-year-oldEucalyptusspecies, which were grown on a planting area with an average slope of 28% leading to decentralized pith in the trees, which is an unequivocal indication of the presence of RW. TW and opposite wood (OW) samples were isolated and subjected to a compression-parallel-to-grain test. It was observed that TW is less resistant and less stiff than the OW.

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Variability in swelling of spruce (Picea abies [L.] Karst.) wood with the presence of compression wood

Journal of Forest Science ◽

10.17221/2019-jfs ◽

2008 ◽

Vol 53 (No. 6) ◽

pp. 243-252 ◽

Cited By ~ 4

Author(s):

V. Gryc ◽

H. Vavrčík ◽

P. Horáček

Keyword(s):

Compression Wood ◽

Longitudinal Direction ◽

Tangential Direction ◽

Transverse Plane ◽

Opposite Wood ◽

Sample Tree ◽

Swelling Coefficient ◽

Hygroscopic Material ◽

The Individual ◽

Shape Changes

Wood is a hygroscopic material that is affected by shape changes. The aim of this study was to analyse the variability of wood swelling in the individual anatomic directions. Wood swelling was examined on a sample tree containing compression wood. With regard to the presence of compression wood, the sample tree was divided into the following three zones: the compression wood zone (CW), the opposite wood zone (OW), and two side wood zones (SWL and SWR). The results show that the wood containing compression wood swells less at the transverse plane (in the radial and tangential direction). Conversely, the swelling of compression wood in the longitudinal direction is higher. The same proportion was established in the swelling coefficient that grew proportionally to the increasing wood density in all anatomic directions. The proportion of compression wood manifested its effects in different ways. Transversely (in the radial and tangential direction) the swelling coefficient decreased proportionally to the increasing percentage of compression wood, longitudinally, however, the opposite was the case.

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Detection and Classification of Norway Spruce Compression Wood in Reflected Light by Means of Hyperspectral Image Analysis

IAWA Journal ◽

10.1163/22941932-90000203 ◽

2009 ◽

Vol 30 (1) ◽

pp. 59-70 ◽

Cited By ~ 19

Author(s):

Philipp Duncker ◽

Heinrich Spiecker

Keyword(s):

Image Analysis ◽

Norway Spruce ◽

Tree Ring ◽

Compression Wood ◽

Hyperspectral Image ◽

Normal Wood ◽

Cross Sectional ◽

Spectral Angle Mapper ◽

Hyperspectral Image Analysis ◽

Reflected Light

A methodology has been developed based on reflected light to detect compression wood in stem cross sections of Norway spruce (Picea abies [L.] Karst.). In addition to quantify the spatial distribution of compression wood, the chronological pattern of its formation is recorded by cross linking the pixel classification to the tree ring sequence. An imaging spectrometer is used to record the spectral characteristics in the visible light and near infrared of the cross-sectional surface. Cross-sectional areas are classified by hyperspectral image analysis into severe compression wood, moderate compression wood, normal wood, and background/cracks. The classification is performed by the Spectral Angle Mapper algorithm, which compares the standardized spectrum of each pixel with reference spectra stored in a spectral library. The reference spectra are obtained from selected training areas of the different compression wood severity classes identified by cell characteristics under a light microscope. The tree ring boundaries are located in a grey scale image which shows the spatial information at wavelength 435 nm and the annual radial increment is measured. The classification accuracy is tested by a confusion matrix and cross-analysed with High-Frequency Densitometry.

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Anatomical Comparison Between Compression Wood and Opposite Wood in a Branch of Korean Pine (Pinus Koraiensis)

IAWA Journal ◽

10.1163/22941932-90001077 ◽

1988 ◽

Vol 9 (3) ◽

pp. 275-284 ◽

Cited By ~ 12

Author(s):

Phil Woo Lee ◽

Young Geun Eom

Keyword(s):

Compression Wood ◽

Pinus Koraiensis ◽

Korean Pine ◽

Qualitative And Quantitative ◽

Opposite Wood

Compression wood and opposite wood formed in the branch of Korean pine (Pinus koraiensis S. et Z.) is described and compared in qualitative and quantitative anatomical aspects.

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WITHIN-TREE VARIATION IN ANATOMICAL PROPERTIES OF COMPRESSION WOOD IN RADIATA PINE

IAWA Journal ◽

10.1163/22941932-90000364 ◽

2004 ◽

Vol 25 (3) ◽

pp. 253-271 ◽

Cited By ~ 48

Author(s):

Lloyd A. Donaldson ◽

Jenny Grace ◽

Geoff M. Downes

Keyword(s):

Wall Thickness ◽

Compression Wood ◽

Microfibril Angle ◽

Basic Density ◽

Radiata Pine ◽

Lumen Diameter ◽

Normal Wood ◽

Lignin Distribution ◽

Opposite Wood ◽

Anatomical Properties

Two trees of radiata pine, one showing severe lean, the other growing almost vertically, were assessed for the presence and anatomical properties of compression wood, including anatomy, lignin distribution, microfibril angle, basic density, radial and tangential lumen diameter and cell wall thickness. Both trees contained significant amounts of compression wood although the severity and amount of compression wood was greater in the leaning tree. Changes in lignin distribution seem to be characteristic of the mildest forms of compression wood with reduced lignification of the middle lamella representing the earliest change observed from normal wood. An increase in microfibril angle was associated with both mild and severe compression wood although examples of severe compression wood with the same or smaller microfibril angles than opposite wood, or with very small microfibril angles, were found. When segregated into mild and severe compression wood the average difference in microfibril angle was 4° and 8° respectively compared with opposite wood. Within-ring distribution of microfibril angle was different in severe compression wood compared to opposite wood with higher angles in the latewood.Severe compression wood showed a 22% increase in basic density compared to mild compression wood and opposite wood. The increased density was accounted for in terms of a 26% increase in tracheid wall thickness throughout the growth ring, offset by a 9% increase in radial lumen diameter, slightly greater in the latewood. There were no significant changes in density or cell dimensions in mild compression wood compared with opposite wood.

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Lignin and carbohydrate variation with earlywood, latewood, and compression wood content of bent and straight ramets of a radiata pine clone

Holzforschung ◽

10.1515/hf.2010.016 ◽

2010 ◽

Vol 64 (1) ◽

Cited By ~ 10

Author(s):

R. Paul Kibblewhite ◽

Ian D. Suckling ◽

Robert Evans ◽

Jennifer C. Grace ◽

Mark J.C. Riddell

Keyword(s):

Radial Direction ◽

Compression Wood ◽

Juvenile Wood ◽

Radiata Pine ◽

Carbohydrate Content ◽

Strongly Correlated ◽

Growth Layer ◽

Opposite Wood ◽

Radial Dimension ◽

Wood Content

Abstract Changes in lignin and carbohydrate content with radial direction, growth-layer number, compression wood (CW) severity, and earlywood (EW) and latewood (LW) origin are described for one near-ground position in each of a severely bent and a nominally straight ramet (tree) of a clone (genotype) of Pinus radiata. Bark-to-bark strips were taken through the pith and the longest radial dimension of the CW side of the discs. Separate EW and LW samples were obtained for most growth layers, yielding a total of 95 samples. Differences in lignin and carbohydrate content between EW and LW were large where CW formation was moderate and small where it was severe. Mannose content was consistently different in the EW and LW of opposite wood (OW) and CW. Results suggested that the inner juvenile wood of OW rings might contain either a galactose-rich galactoglucomannan or a β-1,4-galactan. Consideration of all 95 samples showed that although the contents of galactose, lignin, glucose, and mannose were linearly and strongly correlated with one another, their relationship with xylose and arabinose content was non-linear.

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