Effect of growth suppression and release on strength and specific gravity of yellow-poplar

2010 ◽  
Vol 40 (8) ◽  
pp. 1661-1670
Author(s):  
Thammarat Mettanurak ◽  
Audrey Zink-Sharp ◽  
Carolyn A. Copenheaver ◽  
Shepard M. Zedaker
Keyword(s):  
Specific Gravity ◽  
Growth Ring ◽  
Wood Quality ◽  
Growth Conditions ◽  
Growth Suppression ◽  
Compression Tests ◽  
Yellow Poplar ◽  
Increment Core ◽  
Growth Release ◽  
The Mean

Compression tests and specific gravity analyses were conducted to investigate the impacts of growth suppression and growth release on wood quality in yellow-poplar ( Liriodendron tulipifera L.). Growth ring widths in 23 increment cores were determined and the years of minimum suppression and maximum release were identified based on a modified radial growth averaging technique. Three specimens (1 mm × 1 mm × 4 mm) from both minimum suppression and maximum release years were prepared from each increment core. Data analysis using paired-samples t tests revealed that the mean ultimate crushing stress of the maximum release years was significantly higher than that of the minimum suppression years, yet the mean specific gravity was not significantly different. Even though there was no statistical difference in specific gravity for the two growth conditions studied, the ultimate crushing stress was statistically higher for the release growth specimens. This finding provides support for the concept that growth rate can have an added effect on strength properties that is not entirely captured by specific gravity. Thus, to improve wood quality in yellow-poplar stands, forest managers might consider increasing the likelihood of periods of growth release by controlling the competition experienced by the trees.

scholarly journals WOOD DENSITY OF CLONES OF Eucalyptus urophylla x Eucalyptus grandis IN DIFFERENT CONDITIONS OF GROWTH

FLORESTA ◽  
2014 ◽  
Vol 45 (1) ◽  
pp. 193 ◽  
Author(s):  
Renata Mauri ◽  
José Tarcísio da Silva Oliveira ◽  
Mário Tomazello Filho ◽  
Antônio Marcos Rosado ◽  
Juarez Benigno Paes ◽  
...  
Keyword(s):  
Specific Gravity ◽  
Sampling Method ◽  
Wood Quality ◽  
Genetic Material ◽  
Eucalyptus Grandis ◽  
Growth Conditions ◽  
Eucalyptus Urophylla ◽  
Growth Site ◽  
Wood Specific Gravity

AbstractVariations in the growth site of trees have influence on the internal structure of the trunk. Considering this fact, this study investigated influence of the characteristics of the growth site on wood specific gravity of two clones of Eucalyptus urophyllax Eucalyptus grandis,  approximately six years old, growing in different altitudes and topographies. Furthemore, two methods of sampling of the wood specific gravity were studied, for comparison purpose. Results showed that wood specific gravity underwent variations between growth conditions andtrends in wood specific gravity variations, compared between growth conditions, were the same regardless of the clone. With relation to  sampling method, the wedge was more appropriate for determination of wood specific gravity, in order to extrapolate the disc density. These results provide tools to forestry companies about consolidation of genetic material and its behavior in different growth conditions, to attend wood quality requirements.Keywords: Eucalypt; wood quality;topography; altitude. ResumoDensidade do lenho de clones de Eucalyptus urophylla x Eucalyptus grandis em diferentes condições de crescimento. As variações nas características do local de crescimento das árvores apresentam influência na estrutura interna do tronco. Diante deste fato, foi estudada a influência das características do local de crescimento na densidade básica da madeira de dois clones de EucalyptusurophyllaxEucalyptusgrandis, com aproximadamente seis anos de idade que cresceram emaltitudes e topografias diferentes. Além disso, estudou-se duas formas de amostragem da densidade básica na árvore para fins de comparações. Por meio dos resultados pode-seobservar que a densidade básica da madeira sofreu variações nas diferentes condições de crescimento e que as tendências de variações na densidade básica da madeira, frente às condições de crescimento, foram as mesmas independentemente do clone. Em relaçãoao método de amostragem,a cunha mostrou-se mais apropriada para determinação da densidade básica da madeira para fins de extrapolação da densidade do disco.Estes resultados fornecem subsídios para as empresas do setor florestal no que diz respeito à consolidação de material genético e seu comportamento em diferentes condições de crescimento para atender suas demandas de qualidade de madeira.Palavras-chave:Eucalipto; qualidade de madeira;topografia; altitude.

Selected Properties of Parallel Strand Lumber Made from Southern Pine and Yellow-Poplar

Holzforschung ◽  
2003 ◽  
Vol 57 (2) ◽  
pp. 207-212 ◽  
Author(s):  
Y. Liu ◽  
A.W.C. Lee
Keyword(s):  
Compressive Strength ◽  
Shear Strength ◽  
Specific Gravity ◽  
Moisture Content ◽  
Dimensional Stability ◽  
Modulus Of Rupture ◽  
Southern Pine ◽  
Yellow Poplar ◽  
Average Modulus ◽  
Parallel Strand Lumber

Summary This study was conducted to explore basic physical and mechanical properties of parallel strand lumber (PSL) made exclusively from southern pine and yellow-poplar, respectively, and to examine their relationships using statistical analysis. Small specimens were prepared from commercial southern pine PSL and yellow-poplar PSL billets and tested for specific gravity, moisture content, dimensional stability, bending properties, shear strength and compressive strength. Results indicate average specific gravity of southern pine PSL is higher than that of yellow-poplar PSL, while their average moisture content and dimensional stability are very similar. Southern pine PSL has higher average modulus of elasticity but lower average modulus of rupture than yellow-poplar PSL. While average longitudinal shear strength does not exhibit differences between southern pine PSL and yellow-poplar PSL, average compressive strength of southern pine PSL is higher than that of yellow-poplar PSL. There are positive correlations among modulus of elasticity, modulus of rupture and specific gravity. PSL improves some properties of solid wood from which PSL is made.

IV. On the expansion by heat of metals and alloys

1867 ◽  
Vol 15 ◽  
pp. 220-222
Keyword(s):  
Specific Gravity ◽  
Metals And Alloys ◽  
The Body ◽  
The Other ◽  
Different Temperatures ◽  
The Mean

In a paper “ On the Expansion by Heat of Water and Mercury” *, a method of determining the expansion of bodies is described, by which good results can be obtained with comparatively small quantities of the substances to be experimented with. This method, that of weighing the body in water at different temperatures, has been employed for the present research. The results obtained are given in the following Tables:— From the above the following conclusion is drawn-namely, that just as it may be said that the specific gravity of an alloy is approximately equal to the mean specific gravities of the component metals , so also from the foregoing we may deduce that the volume which an alloy will occupy at any temperature between 0° and 100° is approximately equal to the mean of the volumes o f the component metals at the same temperature, or, in the other words, the cubical or linear coefficients o f expansion by heat of an alloy between 0° and 100° are approximately equal to the mean of the cubical or linear coefficients of expansion by heat o f the component metals .

scholarly journals Growth performance and wood quality of white jabon (Neolamarckia cadamba) progeny testing at Parung Panjang, Bogor, Indonesia

2019 ◽  
Vol 20 (8) ◽  
Author(s):  
Nurul Chaerani ◽  
DEDE J SUDRAJAT ◽  
ISKANDAR Z SIREGAR ◽  
ULFAH J SIREGAR
Keyword(s):  
Specific Gravity ◽  
Moisture Content ◽  
Growth Performance ◽  
Wood Density ◽  
Block Design ◽  
Wood Quality ◽  
Basic Density ◽  
Progeny Testing ◽  
Pilodyn Penetration

Abstract. Chaerani N, Sudrajat DJ, Siregar IZ, Siregar UJ. 2019. Growth performance and wood quality of white jabon (Neolamarckia cadamba) progeny testing at Parung Panjang, Bogor, Indonesia. Biodiversitas 20: 2295-2301. The aim of this study was to evaluate the genetic parameters of growth and wood quality in white jabon progeny test at 54 months old in Parung Panjang, Bogor. The 105 half-sib families obtained from 12 provenances were evaluated in a randomized complete block design with five replications. Wood quality was assessed both in a non-destructive way using a pilodyn and by destructive method using wood sample taker. Results indicated that the mean value ranged from 5.10 to 10.15 m for height, 6.67 to 15.30 cm for diameter, 2.30 to 3.62 cm for pilodyn penetration, 0.66 to 0.82 g/cm3 for wood density, 0.33 to 0.50 for specific gravity, and 66 to 111 % for moisture content, respectively. There were significant differences among 105 families for all traits except moisture content. The high heritability estimate was found for height (0.4-0.69) and basic density (0.27-0.59). Applying 80% selection intensity on diameter and leaving 84 best families in each block will produce a high total genetic gain. Pilodyn penetration had negative correlation with diameter, wood density, and specific gravity.

scholarly journals Relationship between Growth and Wood properties in Agathis sp. Planted in Indonesia

2017 ◽  
Vol 3 (1) ◽  
pp. 1-5
Author(s):  
Futoshi Ishiguri ◽  
Kazuko Makino ◽  
Imam Wahyudi ◽  
Jun Tanabe ◽  
Yuya Takashima ◽  
...  
Keyword(s):  
Wood Quality ◽  
Basic Density ◽  
Tree Breeding ◽  
Wood Properties ◽  
Stem Diameter ◽  
Breeding Programs ◽  
Significant Difference ◽  
Pilodyn Penetration ◽  
The Mean ◽  
The Relationship

The present study clarified the relationship between the growth and wood properties of 54-year-old Agathis sp. trees planted in Indonesia. Stem diameter, pilodyn penetration, and stress-wave velocity (SWV) were measured for all trees (35 trees) in a plot (30  30 m) located almost at the center of a stand. Based on the mean stem diameter, 10 standard trees in a plot were selected for measuring the basic density (BD) and compressive strength parallel to grain (CS). Core samples (5 mm in diameter) were collected from the 10 selected trees to determine BD and CS. The mean stem diameter, pilodyn penetration and SWV in the plot were 40.2  11.3 cm, 23.4  2.1 cm, and 3.85  0.43 km/s, respectively. No  significant correlation coefficeint (r = -0.327, no significance at 5% level) was obtained between stem diameter and SWV. The mean BD and CS in the 10 trees were 0.42  0.03 g/cm3  and 28.1  2.7 MPa, respectively. A significant positive  correlation was observed between BD and CS. Analysis of variance (ANOVA) revealed a significant difference between BD and CS values of the 10 trees, indicating that wood properties may differ among trees with the same standard growth in a stand. From these results, we concluded that wood quality improvement in this species could be achieved by selecting  trees with high density and strength in tree breeding programs.

Effects of Density Control and Fertilization on Log Wood Quality from a Douglas-fir Stand in Western Oregon, USA

2019 ◽  
Vol 66 (2) ◽  
pp. 191-201
Author(s):  
Rapeepan Kantavichai ◽  
Eric C Turnblom ◽  
Eini C Lowell
Keyword(s):  
Specific Gravity ◽  
Modulus Of Elasticity ◽  
Juvenile Wood ◽  
Wood Quality ◽  
Stand Density ◽  
Quality Attributes ◽  
Douglas Fir ◽  
Stem Wood ◽  
Density Control ◽  
Heartwood Percentage

Abstract This study aimed to investigate the effects of juvenile spacing (precommercial thinning), thinning, and fertilization on Douglas-fir butt log (first 4.9 m) and second log (4.9–10 m) quality attributes: juvenile wood percentage, heartwood percentage, rings per inch, specific gravity, and modulus of elasticity. A 41-year-old, 36.6 m site index Douglas-fir stand in western Oregon, USA was selected as the first stand to explore. Nine common silviculture pathway treatments of juvenile spacing, thinning, and fertilization were applied to independent 0.404-hectare plots. Ninety-nine trees were felled and disks cut at five heights along the stem. Wood properties were measured and calculated from the disks for log quality attributes. There was no effect of silvicultural treatments on log heartwood percentage, but significant effects on other log quality attributes were observed. Juvenile wood percentage and rings per inch declined with stand density control and fertilization treatment. Responses to thinning and fertilization in log specific gravity depend on juvenile spacing. Also, thinning and juvenile spacing were shown to have impacts on log modulus of elasticity.

Kraft Pulping and Specific Gravity in the Uppermost Stem of Fertilized Balsam Fir

1975 ◽  
Vol 5 (3) ◽  
pp. 399-402 ◽  
Author(s):  
J. D. Gagnon ◽  
K. Hunt
Keyword(s):  
Specific Gravity ◽  
Boreal Forest ◽  
Kraft Pulping ◽  
Balsam Fir ◽  
Pulp Yield ◽  
Kraft Process ◽  
Forest Region ◽  
The Mean ◽  
Boreal Forest Region

Samples of five pairs of fertilized and non-fertilized 60-year-old natural balsam fir (Abiesbalsamea (L.) Mill.) growing in the Quebec boreal forest region were pulped by the kraft process and the specific gravity was measured. Analyses carried out 7 years after treatment on the last seven terminal internodes revealed the mean pulp yield of trees fertilized exceeded that of non-fertilized by 7%, while the mean specific gravity was about 6% lower.

Microstructure Evolution of AZ31 Magnesium Alloy during Warm Compression Forming

2007 ◽  
Vol 539-543 ◽  
pp. 1813-1817
Author(s):  
Zhi Min Zhang ◽  
Qiang Wang ◽  
B.C. Li ◽  
X. Zhang
Keyword(s):  
Microstructural Evolution ◽  
Room Temperature ◽  
Effective Strain ◽  
Mg Alloy ◽  
Compression Tests ◽  
Az31 Mg Alloy ◽  
Microstructural Evaluation ◽  
Mean Size ◽  
The Mean ◽  
Different Thickness

Warm compression tests of AZ31 Mg alloy were carried out at five temperatures in 30°C intervals from 210°C to 330°C. The samples of different thickness which were machined from as-cast and pre-strained AZ31 billets were compressed into thickness 1mm and then cooled in the air to room temperature. The microstructural evolution of AZ31 Mg alloy was investigated during warm compression forming. The results show that all the samples have undergone a microstructure changes to different scales in the range investigated. The twinning is the predominant deformation mechanism for magnesium alloys at moderate temperatures and its occurrence is dependent on temperature and strain. Microstructural evaluation indicates that the mean size of the recrystallised grains decreases with increasing effective strain and temperature because of sufficient dynamic recrystallization. The original grain has significant influence on microstructural evolution during warm forming.

MODUS OPERANDIIN ASSESSING BIOMASS AND CARBON IN RUBBER PLANTATIONS UNDER VARYING CLIMATIC CONDITIONS

2013 ◽  
Vol 50 (1) ◽  
pp. 40-58 ◽  
Author(s):  
E. S. MUNASINGHE ◽  
V. H. L. RODRIGO ◽  
U. A. D. P. GUNAWARDENA
Keyword(s):  
Rubber Tree ◽  
Rural Poverty ◽  
Growth Conditions ◽  
Climatic Conditions ◽  
Percentage Error ◽  
Carbon Trading ◽  
Average Growth ◽  
Allometric Models ◽  
The Mean ◽  
Simple Growth

SUMMARYIn addition to latex and timber, the rubber tree is useful in the alleviation of rural poverty and also in the mitigation of climate change through fixing atmospheric CO2as biomass. For developing any rubber-based carbon projects, protocols for quantifying biomass and carbon fixed are required. In this context, the present study was aimed at building up allometric models using simple growth indicators (i.e. tree diameter and total height) to assess the timber, biomass and carbon in rubber trees and also to quantify their ontogenetic variation under average growth conditions in two major climatic regimes (i.e. wet and intermediate) of Sri Lanka. All models developed were in the accuracy level of over 88%. The mean absolute percentage error in the validation of allometric models was only 12.9% for timber and less than 5% for biomass and carbon. Under average growth conditions, 1 ha of rubber could produce 208 m3timber, 191 MT biomass and fix 78 MT carbon during its 30-year lifespan in the wet zone and ca. 16% lesser values in the intermediate zone. The applicability of the findings in carbon trading is discussed.

scholarly journals Noise-driven growth rate gain in clonal cellular populations

2016 ◽  
Vol 113 (12) ◽  
pp. 3251-3256 ◽  
Author(s):  
Mikihiro Hashimoto ◽  
Takashi Nozoe ◽  
Hidenori Nakaoka ◽  
Reiko Okura ◽  
Sayo Akiyoshi ◽  
...  
Keyword(s):  
Growth Rate ◽  
Population Growth ◽  
Single Cell ◽  
Single Cells ◽  
Population Level ◽  
Growth Conditions ◽  
Cell Dynamics ◽  
Generation Times ◽  
Complex Population ◽  
The Mean

Cellular populations in both nature and the laboratory are composed of phenotypically heterogeneous individuals that compete with each other resulting in complex population dynamics. Predicting population growth characteristics based on knowledge of heterogeneous single-cell dynamics remains challenging. By observing groups of cells for hundreds of generations at single-cell resolution, we reveal that growth noise causes clonal populations of Escherichia coli to double faster than the mean doubling time of their constituent single cells across a broad set of balanced-growth conditions. We show that the population-level growth rate gain as well as age structures of populations and of cell lineages in competition are predictable. Furthermore, we theoretically reveal that the growth rate gain can be linked with the relative entropy of lineage generation time distributions. Unexpectedly, we find an empirical linear relation between the means and the variances of generation times across conditions, which provides a general constraint on maximal growth rates. Together, these results demonstrate a fundamental benefit of noise for population growth, and identify a growth law that sets a “speed limit” for proliferation.

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