Variation of fibre length within trees of Fraxinusexcelsior

1978 ◽  
Vol 8 (2) ◽  
pp. 253-260 ◽  
Author(s):  
M. P. Denne ◽  
V. Whitbread
Keyword(s):  
Adverse Effect ◽  
Fibre Length ◽  
Ring Width ◽  
Wood Production ◽  
Growth Rings ◽  
Increment Core ◽  
Breast Height ◽  
Leaf Weight ◽  
Old Trees ◽  
European Ash

A systematic internodal analysis within three 22-year-old trees of European ash (Fraxinusexcelsior L.) showed that fibre length increased rapidly from the first ring from the pith outwards to about ring 7 (which coincided with maximum leaf weight within the crown), then increased more slowly to a maximum at about ring 14 (formed below the base of the crown). Since there was little variation in this pattern of increase in fibre length with height in the tree, an increment core taken at breast height should give an adequate indication of fibre length in the whole trunk in trees of this age. Fibre length varied significantly between seasons, independent of age or level in tree.Within growth rings, fibre length increased from earlywood to latewood, reaching a maximum before the end of the latewood. Fibre length was not correlated with ring width between rings (excluding the first five rings from the pith); this suggests that in Fraxinusexcelsior management treatments increasing wood production would not necessarily have an adverse effect on fibre length.

Within-tree variation in wood production and wood quality in sycamore (Acerpseudoplatanus): its relation to crown characteristics

1985 ◽  
Vol 15 (1) ◽  
pp. 56-65
Author(s):  
Richard S. Dodd
Keyword(s):  
Specific Gravity ◽  
Ring Width ◽  
Dry Weight ◽  
Fibre Production ◽  
Main Stem ◽  
Canopy Closure ◽  
Wood Production ◽  
Growth Rings ◽  
Vessel Size ◽  
Leaf Dry Weight

To quantify patterns of wood formation in sycamore (Acerpseudoplatanus L.), the seasonal progress of wood production and structure was followed systematically throughout the outer growth sheath of the main stem and major branches. These data were considered in relation to the profile of leaf dry weight down through the crown in 8- and 12-year-old trees at stages before and after canopy closure, respectively. Mature fibre production was earliest towards the tips of the branches of the midcrown, and spread basipetally along the branches. In the main stem, mature fibre production was earliest at the tip and spread down the tree, taking about 10 days to reach the base of both pre- and post-canopy closure trees. In the stem, later fibre production down the tree was offset by later cessation of fibre maturation basally. Branch data suggested that the pattern of cessation may depend on the branch position, because cessation was latest at the base of the upper branches and at the tip of the lower branches. The maximum rate of fibre production was in the upper stem, several internodes higher than the internode bearing maximum leaf dry weight. Despite this, ring width increased down the stem, presumably as a result of the increased duration of fibre production and increased cell size. Within growth rings, vessel size remained nearly constant before declining sharply towards the end of the ring. Trees with narrower growth rings tended to have more of their ring occupied by declining vessel size suggesting a slight inverse relationship between ring width and specific gravity. Specific gravity increased down the outer growth sheath of the stem, and this increase was associated with systematic trends in fibre and vessel dimensions, together with changes in the relative proportions by area of the different tissues. Although some anatomical characters appeared to vary with the profile of the crown, others appeared to be independent of crown profile.

Early selection for wood density in young coastal Douglas-fir trees

1988 ◽  
Vol 18 (9) ◽  
pp. 1182-1185 ◽  
Author(s):  
Josefina S. Gonzalez ◽  
Jane Richards
Keyword(s):  
Linear Regression ◽  
Wood Density ◽  
Rank Correlation ◽  
Douglas Fir ◽  
Stem Density ◽  
Growth Rings ◽  
Stem Wood ◽  
Breast Height ◽  
Old Trees ◽  
Improvement Effort

Selection age for wood density in vigorous coastal Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) was determined by examining the following: strength of the correlation between total-stem wood density of 50-year-old trees and their breast-height density when the trees were 5 through 30 years old (breast-height age); efficiency in terms of gain per year of tree improvement effort by selecting at ages 5 through 30, relative to selecting at age 50. The linear regression and rank correlation between total-stem and breast-height densities improved as age increased from 5 to 15 years, but showed no significant improvement from 15 to 30 years. Densities of early-growth rings fluctuated considerably and their exclusion from the calculation of breast-height density enhanced the linear regression with total-stem density. Efficiency estimates in terms of gain per year showed an optimum value at age 15, but the estimates for ages 10–14 were nearly as efficient.

Revisiting the transition between juvenile and mature wood: a comparison of fibre length, microfibril angle and relative wood density in lodgepole pine

Holzforschung ◽  
2009 ◽  
Vol 63 (4) ◽  
Author(s):  
Shawn D. Mansfield ◽  
Roberta Parish ◽  
C. Mario Di Lucca ◽  
James Goudie ◽  
Kyu-Young Kang ◽  
...  
Keyword(s):  
Wood Density ◽  
Lodgepole Pine ◽  
Fibre Length ◽  
Microfibril Angle ◽  
Ring Width ◽  
Mature Wood ◽  
Radial Increment ◽  
Breast Height ◽  
Tracheid Length ◽  
Fibre Traits

AbstractIn an attempt to examine the dynamic inter-relationship among wood density and fibre traits [tracheid length and microfibril angle (MFA)] in lodgepole pine (Pinus contorta), 60 trees were sampled in three age classes from four sites in central British Columbia. Breast height discs were taken and relative wood density was measured along two radii. Tracheid length was assessed on isolated 5-year increments from pith to bark at breast height for each tree. MFA was determined every 50 μm and the 5-mm composite intervals from pith to bark per disc at breast height were used in the analysis. Segmented regression was employed to identify the “juvenile to mature wood” transition point, which revealed transition ages of 31, 18 and 15 for wood density, fibre length and MFA, respectively. These traits were related to primary growth, expressed as area increment, ring width, percent earlywood and height increment during the juvenile wood phase. Comparisons of wood and fibre traits showed a higher congruence between the time of transitions for fibre length and MFA (Pearson correlation coefficient 0.52) than that between fibre length and wood density (0.07), and MFA and wood density (0.16). The cessation of early rapid radial increment growth terminated before wood and fibre transitions to mature wood occurred. Fibre length was significantly, but not strongly, related to ring width and percent earlywood (0.35 for both). The duration of juvenile fibre production was not significantly related to height growth.

Effect of Physiological Age and Site on Microfibril Angle in Pinus Radiata

IAWA Journal ◽  
1996 ◽  
Vol 17 (4) ◽  
pp. 421-429 ◽  
Author(s):  
L. A. Donaldson
Keyword(s):  
Pinus Radiata ◽  
Juvenile Wood ◽  
Microfibril Angle ◽  
Basic Density ◽  
Seed Orchard ◽  
Physiological Age ◽  
Growth Rings ◽  
Physiological Aging ◽  
Breast Height ◽  
Old Trees

The effect of physiological age (shoot age at propagation) and site on microfibril angle was examined for seedlings (physiological age = 0 years) and cuttings (physiological age = 5-16 years) of Pinus radiata D. Don. Two trials were examined by measuring microfibril angle in alternate growth rings on breast height discs. In the first trial, two sites were compared for ll-year-old trees propagated from seedlings, and cuttings of comparable genotype, at 0 and 5 years physiological age, respectively. In the second trial, a single site was examined comparing 25-year-old trees propagated from open pollinated seedlings, and cuttings physiologically aged by 12-16 years, originating from 10 seed-orchard clones. In each trial there was a significant effect of physiological age for microfibril angle in the first 9 growth rings with a greater effect in the trees of greater physiological age. Physiological aging produced a significant decrease in microfibril angles in the juvenile wood, on average reducing microfibril angle to values below 35° in trees aged by 12-16 years. Juvenile wood size, as indicated by the point at which microfibril angle gradient changes, was reduced by an average of two rings in both sets of aged cuttings examined. There was no effect of site in the material examined. Differences were consistent among seedling/ramet pairs of similar genotype. The use of aged cuttings rather than seedlings should result in increased stiffness of the juvenile wood and reduced longitudinal shrinkage. However, other changes associated with physiological aging, such as reduced basic density and growth rate, may affect the practicality of using highly.

Wood structure and production within the trunk and branches of Piceasitchensis in relation to canopy formation

1979 ◽  
Vol 9 (3) ◽  
pp. 406-427 ◽  
Author(s):  
M. P. Denne
Keyword(s):  
Light Intensity ◽  
Wall Thickness ◽  
Ring Width ◽  
Dry Weight ◽  
Main Stem ◽  
Wood Production ◽  
Leaf Weight ◽  
Total Leaf ◽  
Leaf Dry Weight ◽  
Tracheid Production

The seasonal progress of wood production and variation in tracheid dimensions were followed systematically along the trunk and main branches of Piceasitchensis trees and analysed in relation to the distribution of light intensity and leaf weight as the canopy develops. The aim was to provide data towards building models to predict effects of management on within-tree patterns of wood production and structure. Tracheid production began earliest at the tips of branches towards the base of the crown; the data show that tracheid production in the main stem began earliest several internodes below the leader, its onset progressing faster and having a shorter distance to travel down the upper branches. Tracheid production appeared to cease simultaneously throughout the trunk in codominant trees; it ceased earlier in severely suppressed trees, which consequently produced little or no latewood.In the main stem, maximum ring width occurred at least one internode above that carrying maximum total leaf dry weight. Maximum rate of tracheid production occurred one or two internodes above those having maximum current leaf dry weight, several internodes above the maximum total leaf weight. In branches, rate of wood production was closely correlated with light intensity.The seasonal increase in wall thickness from early- to latewood occurred more rapidly as you progress down the main stem to below the crown in 16-year-old trees; hence, Mork latewood began progressively earlier lower down the stem; this pattern was not developed in the trunk of younger trees. In all branches, latewood began earlier at the base than at the tip, owing to a more rapid seasonal increase in wall thickness towards the branch base. Tracheid diameter increased from the leader down to midcrown. In branches, partial correlations suggest that tracheid diameter varied with light intensity at the tip but inversely with whorl number at the branch base.

Distribution of juvenile wood in two stems of Larixlaricina

1986 ◽  
Vol 16 (5) ◽  
pp. 1041-1049 ◽  
Author(s):  
K. C. Yang ◽  
C. A. Benson ◽  
J. K. Wong
Keyword(s):  
Juvenile Wood ◽  
Growth Ring ◽  
Ring Width ◽  
Tree Level ◽  
Growth Rings ◽  
Vertical Variation ◽  
Strong Negative Correlation ◽  
Ring Number ◽  
Tracheid Length ◽  
Growth Ring Width

The distribution and vertical variation of juvenile wood was studied in an 81-year-old dominant tree and an 83-year-old suppressed tree of Larixlaricina (Du Roi) K. Koch. Two criteria, growth ring width and tracheid length, were used to demarcate the boundary of juvenile wood. The width of juvenile wood, expressed in centimetres and the number of growth rings, decreased noticeably from the base to the top of the tree. The volume of juvenile wood decreased in a similar pattern. These decreasing trends had a strong negative correlation with the year of formation of cambial initials at a given tree level. The length of these cambial initials decreased with increasing age of formation of the cambial initials. In the juvenile wood zone, there was a positive linear regression between the growth ring number (age) and the tracheid length. The slopes of these regression lines at various tree levels increased as the age of the year of formation of the cambial initials increased. At a given tree level, the length of tracheids increased from the pith to a more uniform length near the bark. However, the number of years needed to attain a more uniform tracheid length decreased from the base to the top of the tree. These relationships suggest that the formation of juvenile wood is related to the year of formation of the cambial initials. Consequently, the juvenile wood is conical in shape, tapering towards the tree top.

Anatomical, Chemical and Mechanical Properties of Fast-Growing Populus × Euramericana cv. ‘74/76’

IAWA Journal ◽  
2014 ◽  
Vol 35 (2) ◽  
pp. 158-169 ◽  
Author(s):  
Zhao Rongjun ◽  
Yao Chunli ◽  
Cheng Xianbao ◽  
Lu Jianxiong ◽  
Fei Benhua ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Sandy Loam ◽  
Physical And Mechanical Properties ◽  
Wood Properties ◽  
Planting Density ◽  
Dry Density ◽  
Growth Rings ◽  
Fast Growing ◽  
Breast Height ◽  
Large Growth

The anatomical characteristics, chemical composition, and physical and mechanical properties of fast-growing Populus × euramericana cv. ‘74/76’ juvenile wood were investigated. Four- to five-year-old clonal plantation trees were harvested from two different experimental sites in the suburbs of Beijing. The Shunyi site had black alkali soil with a planting density of 4 × 6 m and the Miyun site had sandy loam soil with a planting density of 3 × 5 m. The test results showed that the poplar trees from the two sites were both fast growing, with poplar at Shunyi growing faster than at Miyun. There were no significant differences in wood properties between trees grown at the two sites. Fiber length at breast height varied from 872 to 1300 μm between growth rings, average fiber width varied from 21.0 to 25.5 μm and double wall thickness varied from 5.0 to 6.6 μm. Average cellulose, lignin and hemicellulose contents in the samples were 48.9%, 25.4%, and 18.8%, respectively. MFA was higher in the first two growth rings (20–25°), and then decreased rapidly to 12° close to the bark. The average air-dry density at breast height was 401 kg/m3 while the average MOE at breast height was 9.3 GPa. The trees showed large growth rates in both height and stem diameter during the growing season. However, wood properties of the juvenile poplar appeared to be similar to those of poplars with a slower growth rate.

Extending the Place Glacier mass-balance record to AD 1585, using tree rings and wood density

2011 ◽  
Vol 76 (3) ◽  
pp. 305-313 ◽  
Author(s):  
Lisa J. Wood ◽  
Dan J. Smith ◽  
Michael N. Demuth
Keyword(s):  
British Columbia ◽  
Mass Balance ◽  
Large Scale ◽  
Ring Width ◽  
Climate Forcing ◽  
Glacier Mass Balance ◽  
Increment Core ◽  
Engelmann Spruce ◽  
Circulation Indices ◽  
Forcing Mechanisms

AbstractRecognizing that climate influences both annual tree-ring growth and glacier mass balance, changes in the mass balance of Place Glacier, British Columbia, were documented from increment core records. Annually resolved ring-width (RW), maximum (MXD), and mean density (MD) chronologies were developed from Engelmann spruce and Douglas-fir trees sampled at sites within the surrounding region. A snowpack record dating to AD 1730 was reconstructed using a multivariate regression of spruce MD and fir RW chronologies. Spruce MXD and RW chronologies were used to reconstruct winter mass balance (Bw) for Place Glacier to AD 1585. Summer mass balance (Bs) was reconstructed using the RW chronology from spruce, and net balance was calculated from Bw and Bs. The reconstructions provide insight into the changes that snowpack and mass balance have undergone in the last 400 years, as well as identifying relationships to air temperature and circulation indices in southern British Columbia. These changes are consistent with other regional mass-balance reconstructions and indicate that the persistent weather systems characterizing large scale climate-forcing mechanisms play a significant glaciological role in this region. A comparison to dated moraine surfaces in the surrounding region substantiates that the mass-balance shifts recorded in the proxy data are evident in the response of glaciers throughout the region.

Within-Tree Variation in Wood Fibre Biometry And Basic Density of the Urograndis Eucalypt Hybrid (Eucalyptus Grandis × E. Urophylla)

IAWA Journal ◽  
2006 ◽  
Vol 27 (3) ◽  
pp. 243-254 ◽  
Author(s):  
Teresa Quilhó ◽  
Isabel Miranda ◽  
Helena Pereira
Keyword(s):  
Wall Thickness ◽  
Fibre Length ◽  
Eucalyptus Grandis ◽  
Basic Density ◽  
Wood Properties ◽  
Axial Variation ◽  
Average Fibre ◽  
Length Width ◽  
Hybrid Eucalyptus ◽  
Old Trees

Within-tree variations in fibre length, width, wall thickness and wood basic density of Eucalyptus grandis × E. urophylla (urograndis) were studied in five 6.8-yr-old seedling trees and five 5.6-yr-old trees from one clone from Brazil. Samples were taken at 5%, 25%, 35%, 55%, 65% and 90% of stem height and five radial positions (10%, 30%, 50%, 70% and 90% of radius). The tree average fibre length, width and wall thickness were in seed and clone trees: 0.955 mm and 1.064 mm, 18 μm and 20 μm, 3.6 μm and 4.4 μm respectively. The axial variation of fibre dimensions was very low, while there was a consistent but small increasing trend from pith to periphery. The basic density ranged from 397–464 kg/m3 to 486–495 kg/m3 respectively in seedling and clone trees with a low variation along the stem. In comparison with other eucalypt pulpwood, e.g. E. globulus, the urograndis hybrid showed similar fibre dimensions and lower basic density. Overall the within-tree variation of these wood properties was low and age had a small impact on the variation of density and fibre dimensions.

scholarly journals Ultrasonic evaluation regarding the effects of biological corrosion of historical roof trusses

2019 ◽  
Vol 284 ◽  
pp. 07006 ◽  
Author(s):  
Wojciech Skowroński ◽  
Bohdan Stawiski
Keyword(s):  
Fibre Length ◽  
Ultrasonic Pulse ◽  
Strength Parameters ◽  
Growth Rings ◽  
Non Invasive ◽  
Testing Method ◽  
Ultrasonic Evaluation ◽  
Annual Growth Rings ◽  
Strength Tests ◽  
Biological Corrosion

For many years work has been performed to obtain sufficiently accurate correlation between the results of ultrasonic tests and the results of strength tests for evaluation of the strength parameters of wood in a structure. It is also important to ensure the development of methods which will facilitate the work of construction mycologists; that is, non-invasive methods of determining the volume of missing materials caused by biological corrosion. The study presents the idea of the objective examination of the thickness of a corroded layer by measuring the velocity of ultrasonic pulse along the fibre length using for this spot heads with thin waveguides. Another testing method presented in the study is controlling the velocity of ultrasonic wave in the direction tangential to annual growth rings by conducting tests on the corner of the corroded beam.

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