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Barbara L Gartner - One of the best experts on this subject based on the ideXlab platform.
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No Correlation between Latewood Formation and Leader Growth in Douglas-Fir Saplings
IAWA Journal, 2006Co-Authors: Heidi J. Renninger, Barbara L Gartner, Amy T. GrottaAbstract:SUMMARY The width of earlywood and Latewood in conifer xylem may have a profound effect on water transport and storage, vulnerability to embolism, and wood strength, yet the controls over the timing of Latewood formation are unclear. Tracheids differentiating in the cambial zone are influenced by IAA indole-3 acetic acid, the radial concentration gradient of which appears to either increase cell expansion (earlywood) or increase cell wall deposition (Latewood). There are suggestive data that Latewood begins to form when the growth of the leader stops, but defini tive results are lacking. Height growth was measured in 14 Douglas-fir (Pseudotsuga menziesii) saplings at 10 dates between May and August, from the beginning of the growing season until after height growth had ceased. The cambium was also pinned six times between June and July, to induce xylem scarring at known dates. After height growth ceased, saplings were harvested and transverse sections of the wood were made at the pin insertion points. The date at which 95% of the height growth had occurred and the date at which Latewood formation had begun were estimated. Analysis showed no correlation of these data, suggesting that the two phenomena may occur around the same time, but that one is not causal of the other.
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Influence of red alder competition on cambial phenology and Latewood formation in Douglas-fir
IAWA Journal, 2005Co-Authors: Amy T. Grotta, Barbara L Gartner, Steven R. Radosevich, M. HusoAbstract:SUMMARY To better understand the influence of competition on wood formation and wood quality in Douglas-fir ( Pseudotsuga menziesii [Mirb.] Franco), patterns of cambial growth and Latewood production were examined for one growing season in 15-year-old plantations with similar densities but differing Douglas-fir/red alder ( Alnus rubra Bong.) ratios. The treatments consisted of plots having different proportions of Douglas-fir vs. red alder, different red alder planting dates, and one of two total planting densities. Cambial growth was tracked using the pinning method. Cambial activity in most trees began between May 12 and May 23, and ended between August 27 and September 10. Mean date of transition to Latewood was July 6. In the treatment with the highest mean red alder basal area, Douglas-fir trees began radial growth later and ended earlier in the year than those in pure Douglas-fir stands. There was no evident effect of competi tion from red alder on the duration of cambial activity in treatments with intermediate to low red alder basal areas. In all treatments, the duration of radial growth was shorter in smaller-diameter trees. Early transition to Latewood production was also associated with higher red alder basal area. Percent Latewood was unaffected by treatment, but it was dependent on the date of a treeʼs transition to Latewood production.
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how do water transport and water storage differ in coniferous earlywood and Latewood
Journal of Experimental Botany, 2002Co-Authors: Jeanchristophe Domec, Barbara L GartnerAbstract:The goal of this research project was to determine the water transport behaviour of earlywood versus Latewood in the trunk of 21-year-old Douglas-fir [Pseudostuga menziesii (Mirb.) Franco] trees. Specific conductivity (ks) and the vulnerability of xylem to embolism were measured on a single growth ring and in a subset of earlywood and Latewood samples within the same ring. Earlywood/Latewood ratio, trunk water potential (Y) and relative water content (RWC) were used to predict differences in conductivities and vulnerability to embolism. Earlywood has about 11 times the ks of Latewood, and up to 90% of the total flow occurred through the earlywood. Earlywood’s vulnerability to embolism followed the same trend as that of the whole wood, with 50% loss of conductivity at ‐2.2 MPa (P50). Latewood was more vulnerable to embolism than earlywood at high Y, but as Y decreased, the Latewood showed very little further embolism, with a P50 <‐5.0 MPa. The lowest trunk Y estimated in the field was about ‐1.4 MPa, indicating that Latewood and earlywood in the field experienced about 42% and 16% loss of ks, respectively. The higher vulnerability to embolism in Latewood than in earlywood at field Y was associated with higher water storage capacity (21.8% RWC MPa ‐1 versus 4.1% RWC MPa ‐1 , Latewood and earlywood, respectively). The shape of the vulnerability curve suggests that air seeding through Latewood may occur directly through pores in the margo and seal off at lower pressure than earlywood pores.
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How do water transport and water storage differ in coniferous earlywood and Latewood
Journal of experimental botany, 2002Co-Authors: Jeanchristophe Domec, Barbara L GartnerAbstract:The goal of this research project was to determine the water transport behaviour of earlywood versus Latewood in the trunk of 21-year-old Douglas-fir [Pseudostuga menziesii (Mirb.) Franco] trees. Specific conductivity (ks) and the vulnerability of xylem to embolism were measured on a single growth ring and in a subset of earlywood and Latewood samples within the same ring. Earlywood/Latewood ratio, trunk water potential (Y) and relative water content (RWC) were used to predict differences in conductivities and vulnerability to embolism. Earlywood has about 11 times the ks of Latewood, and up to 90% of the total flow occurred through the earlywood. Earlywood’s vulnerability to embolism followed the same trend as that of the whole wood, with 50% loss of conductivity at ‐2.2 MPa (P50). Latewood was more vulnerable to embolism than earlywood at high Y, but as Y decreased, the Latewood showed very little further embolism, with a P50
Jeanchristophe Domec - One of the best experts on this subject based on the ideXlab platform.
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how do water transport and water storage differ in coniferous earlywood and Latewood
Journal of Experimental Botany, 2002Co-Authors: Jeanchristophe Domec, Barbara L GartnerAbstract:The goal of this research project was to determine the water transport behaviour of earlywood versus Latewood in the trunk of 21-year-old Douglas-fir [Pseudostuga menziesii (Mirb.) Franco] trees. Specific conductivity (ks) and the vulnerability of xylem to embolism were measured on a single growth ring and in a subset of earlywood and Latewood samples within the same ring. Earlywood/Latewood ratio, trunk water potential (Y) and relative water content (RWC) were used to predict differences in conductivities and vulnerability to embolism. Earlywood has about 11 times the ks of Latewood, and up to 90% of the total flow occurred through the earlywood. Earlywood’s vulnerability to embolism followed the same trend as that of the whole wood, with 50% loss of conductivity at ‐2.2 MPa (P50). Latewood was more vulnerable to embolism than earlywood at high Y, but as Y decreased, the Latewood showed very little further embolism, with a P50 <‐5.0 MPa. The lowest trunk Y estimated in the field was about ‐1.4 MPa, indicating that Latewood and earlywood in the field experienced about 42% and 16% loss of ks, respectively. The higher vulnerability to embolism in Latewood than in earlywood at field Y was associated with higher water storage capacity (21.8% RWC MPa ‐1 versus 4.1% RWC MPa ‐1 , Latewood and earlywood, respectively). The shape of the vulnerability curve suggests that air seeding through Latewood may occur directly through pores in the margo and seal off at lower pressure than earlywood pores.
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How do water transport and water storage differ in coniferous earlywood and Latewood
Journal of experimental botany, 2002Co-Authors: Jeanchristophe Domec, Barbara L GartnerAbstract:The goal of this research project was to determine the water transport behaviour of earlywood versus Latewood in the trunk of 21-year-old Douglas-fir [Pseudostuga menziesii (Mirb.) Franco] trees. Specific conductivity (ks) and the vulnerability of xylem to embolism were measured on a single growth ring and in a subset of earlywood and Latewood samples within the same ring. Earlywood/Latewood ratio, trunk water potential (Y) and relative water content (RWC) were used to predict differences in conductivities and vulnerability to embolism. Earlywood has about 11 times the ks of Latewood, and up to 90% of the total flow occurred through the earlywood. Earlywood’s vulnerability to embolism followed the same trend as that of the whole wood, with 50% loss of conductivity at ‐2.2 MPa (P50). Latewood was more vulnerable to embolism than earlywood at high Y, but as Y decreased, the Latewood showed very little further embolism, with a P50
Alain Franc - One of the best experts on this subject based on the ideXlab platform.
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Effects of ecological factors on radial growth and wood density components of sessile oak ([i]Quercus petraea[/i] Liebl.) in Northern France
Forest Ecology and Management, 2008Co-Authors: Laurent Berges, Gérard Nepveu, Alain FrancAbstract:Many studies have demonstrated that sessile oak (Quercus petraea Liebl.) wood density is related to ring width, but most have focused on within-tree variability and have never explored large ecological gradients. Other studies indicate that ring width is largely controlled by ecological factors. Hence it has been concluded that ecological factors have an effect on wood density, yet few studies have directly analysed the link between these two variables. The respective effects of climate, soil water capacity and nutrient richness on wood density are also debated. Lastly, sessile oak is a ring-porous species, so that earlywood and Latewood are likely to be differently influenced by ecological factors. Our objectives were (1) to test whether wood density remains under the influence of ecological factors after statistically controlling for ring width, (2) to compare the direction and magnitude of site factors on ring width and mean ring density and (3) to compare the response of earlywood and Latewood. A total of 18,287 rings were analysed from 297 dominant sessile oaks in 99 plots distributed over north-eastern and north-western France in mature, even-aged high-forest stands. Wood density and width were measured using X-ray microdensitometry. Multiple regressions were performed on plot means using ecological factors as predictors, and then using ring width or Latewood proportion as covariable. Regressions were followed by variance partitioning. The ecological factors had an effect on mean ring density that was independent of ring width, but their effect was slight. The percentage of variance explained by ecological factors was twice as high for radial growth components (earlywood, Latewood and total ring width) as for wood density components (earlywood, Latewood and mean ring density). Climatic, water-related and nutrient-related factors did not always have a consistent effect on radial growth and wood density. Earlywood and Latewood responded slightly differently to the ecological factors, with a higher sensitivity of Latewood to climate/water-related factors. Unexpectedly, mean ring density did not correlate with ring width at plot scale, although mean ring density and ring width were nearly always positively correlated within a tree. No correlation between ring width and ring mean density at plot scale may be due to the opposite effects of water-related factors on Latewood proportion and Latewood density. Our results help identify best site conditions for high-quality sessile oak production and argue for a revision of the French management policy.
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Influence of ecological factors and individual effects on radial growth and wood density components for Sessile oak (Quercus petraea Liebl.) in Paris Basin and North-Eastern France by use of mixed linear models
1999Co-Authors: Laurent Berges, Alain Franc, J.c. Hervé, J.m. Gilbert, Gérard NepveuAbstract:Wood formation is influenced by several factors: climatic and soil conditions , silvicultural practises, genetic components, and age of the tree. The biological conditions give the ring characteristics (ring width and density) which are related to timber quality. Tree-to-tree wood quality variability within a plot is said to be wide, especially for oak. Studies have shown that individual genotypes largely explain ring quality variability, whereas site and silviculture have little influence. However, it has not been clearly established if ecological factors have an effect on mean ring density only through their effect on the proportion of Latewood, or if they can have an additional effect on wood density characteristics (earlywood and Latewood densities). The aim of this paper is to answer to this question using a combined analysis of 3 groups of variables: environmental conditions, radial growth components and intra-ring wood density components of sessile oak (Quercus petraea Liebl.). The sample consists in 297 mature oaks in 99 plots stratified according to 3 ecological gradients (macro-climate, soil water capacity and nutrient richness). The plots are located in north-eastern and central France in several even-aged high oak forests. Ecological factors have an influence on Latewood ratio, earlywood and Latewood densities. Ecological factors generally do not have similar effects on (i) radial growth or Latewood ratio and (ii) wood density. Some practical recommendations for high quality sessile oak production are proposed. Then, a linear mixed-effects model allows to split up wood density variability: ecological factors have the least influence compared to cambial age effect or inter-tree variance. One of the main results is the complexity of the relationships between ring width and density. They depend on the level of observation: a strong correlation between ring width and density is generally observed within a tree, but no significant relationship is noticed when considering plot means.
Barry Gardiner - One of the best experts on this subject based on the ideXlab platform.
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variability in water vapour sorption isotherm in japanese larch larix kaempferi lamb earlywood and Latewood influences
International Wood Products Journal, 2015Co-Authors: Callum A.s. Hill, James Ramsay, Barry GardinerAbstract:The objective of this study was to investigate the influence of the earlywood and Latewood of different annual rings of kiln dried Japanese larch wood upon the water vapour sorption properties. Samples of earlywood and Latewood from different lateral positions in the tree at 1·5 m height were exposed to water vapour over a range of different relative humidities to obtain sorption isotherms. A difference was found between the behaviour of the earlywood and Latewood and this became more pronounced as the distance from the pith increased. The results indicated that there was residual water trapped in the cell wall of the Latewood of the more recent annual rings after the first drying curve was completed. However, when the Latewood was exposed to a second sorption cycle much of the residual trapped water was no longer present. Nonetheless, there were still differences in the EMC between the earlywood and Latewood.
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Variability in water vapour sorption isotherm in Japanese Larch (Larix kaempferi Lamb.) – earlywood and Latewood influences
International wood products journal, 2015Co-Authors: Callum A.s. Hill, James Ramsay, Barry GardinerAbstract:The objective of this study was to investigate the influence of the earlywood and Latewood of different annual rings of kiln dried Japanese larch wood upon the water vapour sorption properties. Samples of earlywood and Latewood from different lateral positions in the tree at 1·5 m height were exposed to water vapour over a range of different relative humidities to obtain sorption isotherms. A difference was found between the behavior of the earlywood and Latewood and this became more pronounced as the distance from the pith increased. The results indicated that there was residual water trapped in the cell wall of the Latewood of the more recent annual rings after the first drying curve was completed. However, when the Latewood was exposed to a second sorption cycle much of the residual trapped water was no longer present. Nonetheless, there were still differences in the EMC between the earlywood and Latewood.
Timothy G. Rials - One of the best experts on this subject based on the ideXlab platform.
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Statics and kinetics of water vapor sorption of small loblolly pine samples
Wood Science and Technology, 2007Co-Authors: Trairat Neimsuwan, Siqun Wang, Adam M. Taylor, Timothy G. RialsAbstract:A better understanding of the sorption behavior of different wood structures could be useful in protecting wood against wood deterioration and fungal attack. The purpose of this study was to investigate the effect of differences among earlywood, Latewood, and tree ring location within the stem cross-section of loblolly pine ( Pinus taeda ) on the sorption kinetics and statics of water vapor under ambient conditions. The water vapor sorption of earlywood and Latewood in different tree rings was recorded using a dynamic contact angle analyzer under relative humidity changes from 11 to 89%, as provided by saturated salt solutions. Earlywood had higher sorption rates and diffusion coefficients than Latewood, while outer tree rings had higher sorption rates and diffusion coefficients than inner tree rings. The sorption isotherms of earlywood, Latewood, and different tree ring locations within the stem cross-section were fitted very well by a Hailwood–Horrobin model.
