Knotwood as a window to the indirect measurement of the decay resistance of Scots pine heartwood

Holzforschung ◽  
2007 ◽  
Vol 61 (5) ◽  
pp. 600-604 ◽  
Author(s):  
Outi Karppanen ◽  
Martti Venäläinen ◽  
Anni M. Harju ◽  
Stefan Willför ◽  
Suvi Pietarinen ◽  
...  
Keyword(s):  
Pinus Sylvestris ◽  
Mass Loss ◽  
Scots Pine ◽  
Total Phenolics ◽  
Decay Resistance ◽  
Indirect Measurement ◽  
The Other ◽  
Extractive Content ◽  
Standing Trees ◽  
Further Development

Abstract There is wide variation in the extractive content and decay resistance of Scots pine (Pinus sylvestris L.) heartwood. The heartwood is not visible in standing trees and only poorly visible in timber. Therefore, it is difficult to identify extractive-rich trees, and consequently the most decay-resistant heartwood. On the other hand, knots are clearly visible in standing trees and timber. In the present paper we studied the possibility of measuring the decay resistance of Scots pine heartwood indirectly on the basis of the extractive concentration of knotwood. The material investigated consisted of 40 felled trees with a wide between-tree variation for extractive content and decay resistance of their heartwood. The extractive content of knotwood was found to be four- to five-fold higher than that of heartwood. Statistically significant correlations were found between the mass loss of heartwood and the concentrations of total phenolics and stilbenes in knotwood (r=-0.54, P<0.001 and r=-0.40, P=0.011, respectively), and for the concentration of total phenolics (r=0.42, P=0.008) and stilbenes (r=0.39, P=0.012) between heartwood and knotwood. We suggest further development of this technique in the context of rapid industrial screening of durable pine heartwood.

Measuring the decay resistance of Scots pine heartwood indirectly by the Folin-Ciocalteu assay

2006 ◽  
Vol 36 (7) ◽  
pp. 1797-1804 ◽  
Author(s):  
Anni M Harju ◽  
Martti Venäläinen
Keyword(s):  
Mass Loss ◽  
Scots Pine ◽  
Total Phenolics ◽  
Brown Rot ◽  
Strong Relationship ◽  
Decay Resistance ◽  
Wood Products ◽  
Decay Test ◽  
Decay Tests

To exploit the variation in the natural durability of heartwood timber, screening of a large number of trees or timber is necessary. We suggest that the concentration of total phenolics, measured by the Folin–Ciocalteu (FC) assay, can be used to supplement or even replace in vitro decay tests for screening the variation in the resistance of Scots pine (Pinus sylvestris L.) heartwood timber against the brown-rot fungus Coniophora puteana (Schum. ex Fr.). We screened the juvenile heartwood of 520 Scots pine trees with the FC assay. Samples from 40 trees, with total phenolics concentrations ranging from 1.9 to 21.7 mg tannic acid equivalents (TAE)/g of heartwood, were subjected to an in vitro decay test. The correlation (r) between the total phenolics concentration and mass loss was –0.82 (p < 0.001) in the 7 week long decay test. The relationship was expressed with a linear regression equation: mass loss (mg/g) = 487 – 25 × concentration of total phenolics (mg TAE/g). This strong relationship could be exploited by replacing the decay test with the FC assay to more rapidly assess the durability of wood products.

Wyniki oznaczeń taksonomicznych szczątków drewna

2020 ◽  
pp. 105-106
Author(s):  
Grzegorz Skrzyński
Keyword(s):  
Pinus Sylvestris ◽  
Human Activity ◽  
Scots Pine ◽  
Woody Plants ◽  
The Other ◽  
Taxonomic Identification ◽  
Forest Communities ◽  
Widespread Occurrence ◽  
Przeworsk Culture ◽  
High Share

A number of samples collected during exploration of archaeological features from the Przeworsk culture cremation cemetery were submitted for xylological examination. The samples contained poorly preserved charred remains of wood, which were subjected to taxonomic identification. Anthracological analyses allowed four taxa of woody plants to be identified, with the predominant share of remains belonging to Scots pine Pinus sylvestris. The high share of pine wood fragments may indicate selective acquisition of this species as a material for building funeral pyres. On the other hand, it may reflect the widespread occurrence of this species in the nearby forest communities, which were shaped by human activity.

scholarly journals Resistance of thermally modified and pressurized hot water extracted Scots pine sapwood against decay by the brown-rot fungus Rhodonia placenta

2019 ◽  
Vol 78 (1) ◽  
pp. 161-171 ◽  
Author(s):  
Michael Altgen ◽  
Suvi Kyyrö ◽  
Olli Paajanen ◽  
Lauri Rautkari
Keyword(s):  
Cell Wall ◽  
Mass Loss ◽  
Scots Pine ◽  
Elevated Temperatures ◽  
Brown Rot ◽  
Decay Resistance ◽  
Hot Water ◽  
Decay Fungi ◽  
Effective Reduction ◽  
Cell Wall Porosity

AbstractThe thermal degradation of wood is affected by a number of process parameters, which may also cause variations in the resistance against decay fungi. This study compares changes in the chemical composition, water-related properties and decay resistance of Scots pine sapwood that was either thermally modified (TM) in dry state at elevated temperatures (≥ 185 °C) or treated in pressurized hot water at mild temperatures (≤ 170 °C). The thermal decomposition of easily degradable hemicelluloses reduced the mass loss caused by Rhodonia placenta, and it was suggested that the cumulative mass loss is a better indicator of an actual decay inhibition. Pressurized hot water extraction (HWE) did not improve the decay resistance to the same extent as TM, which was assigned to differences in the wood-water interactions. Cross-linking reactions during TM caused a swelling restraint and an effective reduction in moisture content. This decreased the water-swollen cell wall porosity, which presumably hindered the transport of degradation agents through the cell wall and/or reduced the accessibility of wood constituents for degradation agents. This effect was absent in hot water-extracted wood and strong decay occurred even when most hemicelluloses were already removed during HWE.

scholarly journals Ungulate damage on Scots pines in Mediterranean environments: effects of association with shrubs

2001 ◽  
Vol 79 (6) ◽  
pp. 739-746 ◽  
Author(s):  
José M Gómez ◽  
José A Hódar ◽  
Regino Zamora ◽  
Jorge Castro ◽  
Daniel García
Keyword(s):  
Spatial Structure ◽  
Pinus Sylvestris ◽  
Plant Communities ◽  
Scots Pine ◽  
The Other ◽  
High Mountain ◽  
Associational Resistance ◽  
Southeastern Spain ◽  
Associational Susceptibility ◽  
Mechanical Barrier

The spatial structure of plant communities as well as the quality and abundance of neighbours can strongly influence the intensity of herbivory suffered by a plant. In this paper, we study the effect of the association with shrubs on the ungulate herbivory suffered by Scots pine (Pinus sylvestris var. nevadensis Christ., Pinaceae) saplings in two isolated, fragmented populations in southeastern Spain. For this, we monitored herbivory on saplings with regard to the microhabitat in which they grew. We distinguished pines growing in open interspaces, on the edge of shrubs and within the canopy of shrubs, and also we distinguished four functional types of shrubs: thorny shrubs, nonthorny shrubs, thorny scrubs, and nonthorny scrubs. Our results show that association with shrubs increases the damage inflicted on Scots pine saplings. In fact, saplings growing in the open patches, far from the shrubs, escaped from herbivory more frequently and incurred less damage than did saplings growing close to shrubs. However, herbivory was also reduced when pine saplings were completely surrounded by shrubs, since then they served as a mechanical barrier. The type of neighbouring shrub did not affect the overall damage suffered by pines, despite the fact that the ungulates damaged the nonthorny scrubs more intensely than the other kinds of shrubs. Consequently, saplings have an advantage when growing within the canopy of shrubs; these constitute key microsites for pine recruitment in these Mediterranean forests.Key words: associational resistance, associational susceptibility, mammalian herbivory, Mediterranean high mountain, neighbouring effects, Pinus sylvestris var. nevadensis.

scholarly journals Early-arriving saproxylic beetles developing in Scots pine stumps: effects of felling type and date

2012 ◽  
Vol 58 (No. 11) ◽  
pp. 503-512 ◽  
Author(s):  
J. Foit
Keyword(s):  
Species Richness ◽  
Czech Republic ◽  
Species Composition ◽  
Pinus Sylvestris ◽  
Scots Pine ◽  
Saproxylic Beetles ◽  
The Other ◽  
The Czech Republic ◽  
Clear Cut ◽  
Species Richness And Diversity

A total of 320 Scots pine (Pinus sylvestris L.) low stumps were analysed within two stands (one stand was thinned, and the other stand was subjected to clear-cut final felling) in the Drahansk&aacute; Highlands in the Czech Republic. Each stand was divided into four parts, and the felling of each part was performed on different dates during 2006 (February, May, August and November). The fauna of early-arriving saproxylic beetles inhabiting the stumps was investigated by peeling the bark in two vegetation periods after the felling. A total of 17 species of beetles were found. The felling type and date affected the species composition of the recorded assemblages, with the felling date being considerably more important than the type. The species richness and diversity did not differ significantly between the felling types, but significant differences were found among the felling dates. Several associations of particular species with certain felling types or dates were also found.

scholarly journals Seasonal and geographical variation of terpenes, resin acids and total phenolics in nursery grown seedlings of Scots pine (Pinus sylvestris L.)

1994 ◽  
Vol 128 (4) ◽  
pp. 703-713 ◽  
Author(s):  
A. NERG ◽  
P. KAINULAINEN ◽  
M. VUORINEN ◽  
M. HANSO ◽  
J. K. HOLOPAINEN ◽  
...  
Keyword(s):  
Pinus Sylvestris ◽  
Scots Pine ◽  
Geographical Variation ◽  
Total Phenolics ◽  
Resin Acids

Genetic variation in the decay resistance of Scots pine wood against brown rot fungus

2001 ◽  
Vol 31 (7) ◽  
pp. 1244-1249 ◽  
Author(s):  
Anni M Harju ◽  
Martti Venäläinen ◽  
Egbert Beuker ◽  
Pirkko Velling ◽  
Hannu Viitanen
Keyword(s):  
Genetic Variation ◽  
Mass Loss ◽  
Scots Pine ◽  
Brown Rot ◽  
Decay Resistance ◽  
Phenotypic Variance ◽  
Increment Core ◽  
Genetic Components ◽  
Brown Rot Fungus ◽  
The Mean

The role of genotype in the durability of Scots pine (Pinus sylvestris L.) wood against decay by brown rot fungus (Coniophora puteana (Schum. ex Fr.) Karst. (strain Bam EBW 15)) was studied in a laboratory test. The wood material was obtained from 32-year-old half-sib progenies of Scots pine. The increment core samples of sapwood and juvenile heartwood were decayed using a modification of the standardized EN 113 method. The mean densities of the sapwood and heartwood samples were 391 and 337 mg·cm–3, respectively, and the mean mass losses were 114 and 80 mg·cm–3, respectively. The additive genetic components were small compared with the total phenotypic variance, which resulted in small narrow-sense heritabilities in mass loss. The most marked feature was the wide phenotypic variation in mass loss observed in heartwood (range 199 mg·cm–3) compared with sapwood (range 72 mg·cm–3) samples. Low heritability, together with the relatively high coefficient of additive genetic variation (CVA) in heartwood mass loss, suggests that advances in breeding can only be made through intensive testing in the environments which the studied experiment represents.

Mass loss and moisture dynamics of Scots pine (Pinus sylvestris L.) exposed outdoors above ground in Sweden

Holzforschung ◽  
2005 ◽  
Vol 59 (2) ◽  
pp. 183-189 ◽  
Author(s):  
Åsa Rydell ◽  
Mikael Bergström ◽  
Torbjörn Elowson
Keyword(s):  
Moisture Content ◽  
Pinus Sylvestris ◽  
Mass Loss ◽  
Scots Pine ◽  
Annual Ring ◽  
Water Storage ◽  
Ring Width ◽  
Moisture Uptake ◽  
Annual Ring Width ◽  
Moisture Dynamics

Abstract The durability of 566 Scots pine (Pinus sylvestris) samples was tested during a period of 9 years of exposure to weather in Sweden. The parameters investigated were heartwood/sapwood, origin, surface treatment, end-seal, storage and drying method, annual ring width and density. The weight was measured on 67 occasions during 9 years in order to assess the moisture content of the samples. The mass loss was determined for each sample at the end of the trial. Sapwood had a higher moisture uptake and a higher mass loss compared with heartwood. Even if sapwood was painted with an impermeable paint and then end-sealed, it still had higher average moisture content than heartwood. The results also demonstrated that sapwood was more sensitive to different handling conditions than heartwood. Sapwood was sensitive to air-drying and water storage, which was evident in the higher moisture uptake. In terms of mass loss, some differences were evident but they were not statistically significant due to the large standard deviation of the sapwood samples from water-stored logs. The only positive influence of water storage was on samples end-dipped in oil. One explanation could be that water storage led to increased permeability due to bacterial attack, which in turn enhanced the penetration of the oil. Heartwood had low and stable moisture dynamics during the test period, almost independent of treatment or handling conditions. No correlation with moisture uptake or mass loss was evident among annual ring width, origin or density.

Microstructure and stiffness of Scots pine (Pinus sylvestris L) sapwood degraded by Gloeophyllum trabeum and Trametes versicolor – Part I: Changes in chemical composition, density and equilibrium moisture content

Holzforschung ◽  
2012 ◽  
Vol 66 (2) ◽  
Author(s):  
Thomas K. Bader ◽  
Karin Hofstetter ◽  
Gry Alfredsen ◽  
Susanne Bollmus
Keyword(s):  
Moisture Content ◽  
Pinus Sylvestris ◽  
Mass Loss ◽  
Sample Size ◽  
Equilibrium Moisture Content ◽  
Scots Pine ◽  
Trametes Versicolor ◽  
Mass Density ◽  
Gloeophyllum Trabeum ◽  
Physical And Chemical

Abstract Fungal degradation alters the microstructure of wood and its physical and chemical properties are also changed. While these changes are well investigated as a function of mass loss, mass density loss and changes in equilibrium moisture content are not well elucidated. The physical and chemical alterations are crucial when linking microstructural characteristics with macroscopic mechanical properties. In the present article, a consistent set of physical, chemical and mechanical characteristics is presented, which were measured on the same sample before and after fungal degradation. In the first part of this two-part contribution, elucidating microstructure/stiffness-relationships of degraded wood, changes in physical and chemical data are presented, which were collected from specimens of Scots pine (Pinus sylvestris) sapwood degraded by Gloeophyllum trabeum (brown rot) and Trametes versicolor (white rot) for up to 28 weeks degradation time. A comparison of mass loss with corresponding mass density loss demonstrated that mass loss entails two effects: firstly, a decrease in sample size (more pronounced for G. trabeum), and secondly, a decrease of mass density within the sample (more pronounced for T. versicolor). These two concurrent effects are interrelated with sample size and shape. Hemicelluloses and cellulose are degraded by G. trabeum, while T. versicolor was additionally able to degrade lignin. In particular because of the breakdown of hemicelluloses and paracrystalline parts of cellulose, the equilibrium moisture content of degraded samples is lower than that in the initial state.

Application of scanning UV microspectrophotometry for the topochemical detection of lignin within individual cell walls of brown-rotted Scots pine (Pinus sylvestris L.) sapwood

Holzforschung ◽  
2006 ◽  
Vol 60 (6) ◽  
pp. 601-607 ◽  
Author(s):  
Ilze Irbe ◽  
Guna Noldt ◽  
Gerald Koch ◽  
Ingeborga Andersone ◽  
Bruno Andersons
Keyword(s):  
Weight Loss ◽  
Pinus Sylvestris ◽  
Scots Pine ◽  
Cell Walls ◽  
Individual Cell ◽  
Oxidative Modification ◽  
The Other ◽  
Wood Degradation ◽  
Lower Extent ◽  
Uv Microspectrophotometry

Abstract Brown rotted Scots pine (Pinus sylvestris) sapwood was studied using scanning UV microspectrophotometry. Wood blocks were exposed to the fungus Coniophora puteana (Schum.: Fr.) Karst. (BAM Ebw.15) for 6, 8, 10, 30, and 50 days. No wood weight loss was detected in the initial decay periods. On the other hand, point analyses of lignin distribution in wood cells revealed higher absorbance after 6–10 days of decay, which we interpret as an increase in the absorption coefficient of lignin due to its oxidative modification by the fungus. Uneven wood degradation occurred in the later periods (30 and 50 days), with both significantly decayed and visually sound cells observed. The decayed cells showed a higher absorbance at 280 nm, although the apparently sound cells were also degraded to a lower extent. Degradation of lignin-rich compounds in middle lamellae and cell corners was not observed during fungal attack.

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