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Basic wood properties of second-growth sitka spruce

https://library.fpinnovations.ca/en/permalink/fpipub5534
Author
Jozsa, Les A.
von Schilling, B.
Sen, P.
Date
January 1993
Edition
37459
Material Type
Research report
Field
Sustainable Construction
Author
Jozsa, Les A.
von Schilling, B.
Sen, P.
Contributor
British Columbia. Ministry of Forests. Queen Charlotte Forest District.
Date
January 1993
Edition
37459
Material Type
Research report
Physical Description
38 p.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Advanced Wood Materials
Subject
Second growth
Picea
Physical properties
Mechanical properties
Growth
Series Number
W-1446
Location
Vancouver, British Columbia
Language
English
Abstract
The basic wood properties of 45-year-old second-growth sitka spruce were examined to determine if rapid growth produces poor wood quality. Five dominant and codominant trees were sampled from each of four stands with stocking densities of 520, 640, 1080, and 1520 stems/ha. Stem size, extent of live crown, yearly wood relative density trends, and longitudinal shrinkage were measured.
Picea sitchensis - Mechanical properties
Picea sitchensis - Physical properties
Second growth
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Confirmation of stand density effects on lodgepole pine wood characteristics

https://library.fpinnovations.ca/en/permalink/fpipub5514
Author
Middleton, G.R.
Jozsa, Les A.
Munro, B.D.
Sen, P.
Date
July 1995
Edition
37389
Material Type
Research report
Field
Sustainable Construction
Author
Middleton, G.R.
Jozsa, Les A.
Munro, B.D.
Sen, P.
Contributor
British Columbia Ministry of Forests. Silviculture
Date
July 1995
Edition
37389
Material Type
Research report
Physical Description
34 p.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Advanced Wood Materials
Subject
Stands
Quality control
Qualitative analysis
Pinus contorta
Pinus
Physical properties
Growth
Series Number
W-1234
Location
Vancouver, British Columbia
Language
English
Abstract
In a previously completed study, lumber obtained from a 95-year old lodgepole pine sample representing a final stand density of 700 live stems/hectare (s/ha) was found to have relatively low modulus- of-rupture (MOR) and modulus of elasticity (MOE). It was determined that this resulted from lower than average basic wood density, and larger than average knot size particularly in large diameter trees. It was also determined that average MOR and MOE could be predicted to some extent (R2 > .60) on the basis of tree diameter-at-breast height (d.b.h.) and breast-height average basic wood density. Before accepting the above results as typical of lodgepole pine of similar age and final stand density, it was considered important to compare the relationships between d.b.h. and breast-height wood density observed in this 700 s/ha sample with that of trees in open-stand-densities in other regions. Average branch size added only marginally to explained variation in the predictive equation, but knot size is known to effect lumber strength. Thus a measure of branch size was included in the current study plan. Biogeoclimatic zones were chosen as the basis for regional comparisons. A minimum of 30 trees were selected from open-stand sites in each of the following five biogeoclimatic zones: Montane Spruce (MS), Engelmann Spruce-Subalpine Fir (ESSF), Interior Douglas-Fir (IDF), Interior Cedar-Hemlock (ICH) and Sub-Boreal Spruce (SBS). Sampling was systematic by d.b.h. to ensure representation of small, medium and large diameter trees. Stem counts were made in 1/200 ha plots around each sample tree to ensure that samples were indicative of a relatively open stand density. Average basic wood density at breast height was determined from two pith-to-bark increment cores obtained from each sample tree. The size and height of the largest branch in the first 5 m of tree height was measured and recorded. Average basic wood density values and estimates of branch size obtained for the five samples in this study were compared to the values and estimates obtained from the original 700 s/ha sample site. Basic wood density obtained from three of the sites was not significantly different from that of the 700 s/ha sample. It was significantly higher in one site (ICH) and significantly lower in another (ESSF). The higher wood density was possibly the result of a slower growth rate to 30 years combined with older average tree age. The significantly lower wood density was attributed to a younger average stand age (80 years). Basic wood density showed a consistent relationship with d.b.h. in all of the tree samples, tending down as d.b.h. increased. There was a less consistent relationship between knot size and d.b.h. but what relationship there was would serve to reinforce the effect of differences in wood density on lumber strength and stiffness. Average size of the largest knots was smallest in the tree sample where wood density was highest, and largest in the sample where wood density was lowest. Important lumber strength determining tree characteristics (wood density and knot size) that resulted in the low MOE and MOR at the original 700 s/ha sample site were found to be unexceptional when compared to trees of similar age and final stand densities in other biogeoclimatic zones. Although a slower than average growth rate to 30 years offers a plausible explanation for the higher than expected wood density in the ICH sample, further investigation is recommended.
Pinus contorta Dougl. var. latifolia - Density
Density - Influence on physical properties
Stand density
Growth - Influence on quality
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Lodgepole pine product yields related to differences in stand density

https://library.fpinnovations.ca/en/permalink/fpipub5512
Author
Middleton, G.R.
Jozsa, Les A.
Palka, L.C.
Munro, B.D.
Sen, P.
Date
December 1994
Edition
37368
Material Type
Research report
Field
Sustainable Construction
Author
Middleton, G.R.
Jozsa, Les A.
Palka, L.C.
Munro, B.D.
Sen, P.
Date
December 1994
Edition
37368
Material Type
Research report
Physical Description
1 v.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Advanced Wood Materials
Subject
Recovery
Quality control
Qualitative analysis
Pinus contorta
Pinus
Growth
Grading
Series Number
W-1181
Location
Vancouver, British Columbia
Language
English
Abstract
Tree and log characteristics, wood properties, visually graded lumber yields, and machine-stress-rated (MSR) lumber yields were determined for 95 year-old lodgepole pine (Pinus contorta Dougl. var. latifolia Engelm.) trees on good sites. A total of 220 trees were selected systematically by diameter-at-breast height (d.b.h.). Based on measurements of stand density made for plots around each sample tree, three samples were obtained which represented end-of-rotation stand densities of 700, 1100 and 1900 live stems/hectare (s/ha). Logs were sawn to maximize the yield of wide dimension lumber. Lumber recovery factor increased with increasing tree d.b.h. class, but due to greater stem taper, it was generally lowest for a given d.b.h. class in the 700 s/ha stand density class. Due to decreasing knot size, yields of Select Structural lumber increased as stand density increased (45.6, 62.5 and 65.4% for the 700, 1100 and 1900 s/ha samples respectively) but knots were small enough that a high proportion of lumber (greater than 90%) was visually graded No.2 & Btr. in all three stand density classes. Wood basic relative density was significantly inversely related to d.b.h., but was not significantly related to crown persistence or stand density. Lumber modulus-of-rupture (MOR) and modulus-of-elasticity (MOE) decreased as tree d.b.h. increased. Wide dimension lumber from open-grown trees generally failed to meet in-grade specifications for MOR and MOE. Lower MOR and MOE values were reflected in reductions in MSR yields. The juvenile wood proportion of tree stems, defined either as 15 or 30 annual rings from the pith, was only weakly related to lumber MOR and MOE. Kiln drying degrade increased with stand density class and ranged from 3% of pieces in the 700 s/ha sample to 7% of pieces in the 1900 s/ha sample. Drying degrade was essentially unrelated to proportions of juvenile wood. Application of study results to theoretical tree size and volume distributions generated by a stand growth and yield model (TASS) produced stand yields which in terms of lumber recovery, and premium structural and appearance grades, would rank stand densities in the following descending order: 1100, 700 and 1900 s/ha. Study results indicate that, for lodgepole pine grown on good sites, stand managers will achieve the optimal combination of lumber yield and grade by targeting a medium final stand density. Further research is underway to determine if the inverse relationship between average basic wood density and large diameter trees recorded in this regional study persists in other biogeoclimatic zones. It is important to note that, because of the systematic method of selecting trees by d.b.h. and stand density classes, the lumber strength and stiffness results obtained in this study are not representative of the current lodgepole pine resource in general.
Pinus contorta Dougl. var. latifolia - Grading
Pinus contorta Dougl. var. latifolia - Recovery
Pinus contorta Dougl. var. latifolia - Density
Growth - Influence on quality
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Lodgepole pine product yields related to differences in stand density.

https://library.fpinnovations.ca/en/permalink/fpipub5516
Author
Middleton, G.R.
Jozsa, Les A.
Palka, L.C.
Munro, B.D.
Sen, P.
Date
December 1995
Edition
37398
Material Type
Research report
Field
Sustainable Construction
Author
Middleton, G.R.
Jozsa, Les A.
Palka, L.C.
Munro, B.D.
Sen, P.
Date
December 1995
Edition
37398
Material Type
Research report
Physical Description
92 p.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Advanced Wood Materials
Subject
Quality control
Qualitative analysis
Pinus contorta
Pinus
Growth
Grading
Series Number
Special Publication ; SP-35
W-1279
Location
Vancouver, British Columbia
Language
English
ISSN
ISSN No. 0824-2119
Abstract
Tree and log characteristics, wood properties, visually graded lumber yields, and machine-stress-rated (MSR) lumber yields were determined for 95 year-old lodgepole pine (Pinus contorta Dougl. var. latifolia Engelm.) trees on good sites in southeastern British Columbia. A total of 220 trees were selected stratified by diameter-at-breast height (d.b.h.). Based on measurements of stand density made for plots around each sample tree, three samples were obtained which represented end-of-rotation stand densities of 700, 1100 and 1900 live stems/hectare (s/ha). Logs were sawn to maximize the yield of wide dimension lumber. Lumber recovery factor increased with increasing tree d.b.h. class, but due to greater stem taper, it was generally lowest for a given d.b.h. class in the 700 s/ha stand density class. Due to decreasing knot size, yields of Select Structural lumber increased as stand density increased (45.6, 62.5 and 65.4% for the 700, 1100 and 1900 s/ha samples respectively) but knots were small enough that a high proportion of lumber (> 90%) was visually graded No.2 & Btr. in all three stand density classes. Wood basic relative density was significantly inversely related to d.b.h., but was not significantly related to crown persistence or stand density. Lumber modulus-of-rupture (MOR) and modulus-of-elasticity (MOE) decreased as tree d.b.h. increased. Wide dimension lumber from open-grown trees generally failed to meet in-grade specifications for MOR and MOE. Lower MOR and MOE values were reflected in reductions in MSR yields. The juvenile wood proportion of tree stems, defined either as 15 or 30 annual rings from the pith, was only weakly related to lumber MOR and MOE. Kiln drying degrade increased with stand density class and ranged from 3% of pieces in the 700 s/ha sample to 7% of pieces in the 1900 s/ha sample. Drying degrade was essentially unrelated to proportions of juvenile wood. Application of study results to theoretical tree size and volume distributions generated by a stand growth and yield model (TASS) produced stand yields which in terms of lumber recovery, and premium structural and appearance grades, would rank stand densities in the following descending order: 1100, 700 and 1900 s/ha. Study results indicate that, for lodgepole pine grown on good sites, stand managers will achieve the optimal combination of lumber yield and grade by targeting a medium final stand density. Further research is underway to determine if the inverse relationship between average basic wood density and large diameter trees recorded in this regional study persists in other biogeoclimatic zones. It is important to note that, because the tree samples were stratified by d.b.h. and stand density classes, the lumber strength and stiffness results obtained in this study are not representative of the current lodgepole pine resource in general.
Pinus contorta Dougl. var. latifolia - Density
Pinus contorta Dougl. var. latifolia - Grading
Pinus contorta Dougl. var. latifolia - Recover
Growth - Influence on quality
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Relative density trends in second-growth lodgepole pine

https://library.fpinnovations.ca/en/permalink/fpipub5498
Author
Jozsa, Les A.
Sen, P.
Date
March 1992
Edition
37281
Material Type
Research report
Field
Sustainable Construction
Author
Jozsa, Les A.
Sen, P.
Date
March 1992
Edition
37281
Material Type
Research report
Physical Description
35 p.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Advanced Wood Materials
Subject
Second growth
Pinus contorta
Pinus
Growth
Series Number
Forestry Canada No. 28
Contract no. 1212K023
W-934
Location
Vancouver, British Columbia
Language
English
Abstract
11 lodgepole pine study sites were selected in British Columbia, and Alberta for a study of basic wood properties. At each site 20 trees were selected, felled, and sampled at five height levels for relative density, fiber length, longitudinal shrinkage, lignin and extractives content determinations. This report presents wood relative density trends, stem sizes, and juvenile-mature wood distribution in 80 to 100 year-old lodgepole pine stands which grew under various stocking densities (500 - 2300 stems/hectare). In all three diameter classes sampled, a high degree of intra-ring density uniformity was evident, as low density earlywood and high density latewood ranged between 0.30 to 0.60 for western-red-cedar and Douglas-fir 0.25 to 0.80. This density homogeneity contributes to excellent machinability and veneer peeling qualities. When lodgepole pine trees of similar environment were compared at equal age and equal height level there was no relationship between growth rate and relative density. Comparatively low density wood in the large diameter trees was the result of normal physiological influence of the live crown. As crown dominance is reduced, through higher stocking densities, wood density is enhanced in the lower bole but at the expense of log size. And herein lies the paradox because both the solid wood and pulp and paper industry experts believe that industry will maximize profit by planning to grow, harvest, and process larger, rather than smaller, trees.
Pinus contorta Dougl. var. latifolia - Density
Second growth
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Yellow-cypress wood quality

https://library.fpinnovations.ca/en/permalink/fpipub5499
Author
Jozsa, Les A.
Sen, P.
Date
March 1992
Edition
37282
Material Type
Research report
Field
Sustainable Construction
Author
Jozsa, Les A.
Sen, P.
Date
March 1992
Edition
37282
Material Type
Research report
Physical Description
35 p.
Sector
Wood Products
Field
Sustainable Construction
Research Area
Advanced Wood Materials
Subject
Wood quality
Wood
Quality control
Qualitative analysis
Series Number
Forestry Canada No. 31
Contract no. 1212K022
W-935
Location
Vancouver, British Columbia
Language
English
Abstract
There is very little information about basic wood properties for yellow-cypress. This report presents wood relative density trends, stem sizes, heartwood-sapwood distribution, and longitudinal shrinkage characteristics in 13 old-growth, 10 second-growth, and 20 in off-site (out of its natural range) plantation-grown yellow cypress trees. Based on these comparisons and previous work at Forintek, yellow-cypress wood appears to be the most homogenous commercial softwood species in Canada. In terms of wood relative density yellow-cypress had comparatively high-density juvenile core-wood. The old-growth resource average density of 0.42 was met or surpassed in all three age classes. Yellow-cypress resource managers and the users of yellow- cypress wood can be confident that wood quality can be maintained in second-growth stands. Wood density comparisons with other softwoods and Japanese hinoki demonstrated why yellow-cypress wood is an excellent substitute for hinoki in terms of product properties.
Wood quality
Chamaecyparis nootkatensis
Documents
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6 records – page 1 of 1.