Wood Quality… · RELATIVE DENSITY OF WOOD 33.0 0.5 0.4 0.3 0.2 0.1 western redcedar subalpine fir Interior spruce Amabilis fir lodgepole pine western hemlock yellow-cypress Douglas-fir

Wood Quality…Impact on Product Yields,Grades and Value

Wood Quality…Impact on Product Yields,Grades and Value

W O R K B O O K

Wood Quality… Impact on Product Yields, Grades and Value.

1

Wood Quality… Impact on Product Yields, Grades and Value1.0INTRODUCTION, HISTORICAL TRENDS



2


Wood Quality… Impact on Product Yields, Grades and Value4.0GLOBAL TRENDS


3


Population (Billions)14

12

10

8

6

4

2

01850 1880 1910 1940 1970 2000 2030 2060 2090

World Population 1850 to 2100


Al Fe Steel Zn Sn Cu Ni

60

50

40

30

20

10

0

Globalconsumption (%)

Japan, Germany, United Kingdom, France

United States

Global Consumption of Raw Materialsby 10.3% of Global Population


Temperate coniferous and mixed forests

Tropical rain forests


4


Wink Sutton holds

”The Wedge”;

a 1.8 litre piece

of wood that

represents the

average amount

of wood used

each day by each

person on earth.

(Based on FAO figures: total wood harvested)population of earth


Industrial Roundwood1.7 billion m3

Fuelwood1.8 billion m3


3.4

1.9

Billions (m3) 0.56

Saw/veneer logs

Other industrial roundwood

Pulpwood

Fuelwood/charcoal

Wood-based panels, ROW

Wood-based panels, U.S.

Wood-based panels, Canada

HW lumber, World

SW lumber, ROW

SW lumber, Canada

Global Production of Fibre

Source: FAO


5


SoftwoodsSweden

Canada/Pacific

Canada/Interior

Canada/East

US/South

Chile

New Zealand

Brazil

HardwoodsSweden

US/South

Portugal

Brazil

South Africa

Chile (Euca)

40 30 20 10 0 10 20 30 40 50 60 70 80

(m3/ha/yr) (US $/m3)

Growth and Mill DeliveredCost of Pulpwood – 1/91

Wood Quality… Impact on Product Yields, Grades and Value12.0BRAZIL AND NEW ZEALAND


6


This thinning operation is at

age 23. About 3 years later

this stand will be clearcut

and replanted.


26-year-old Caribbean

pine hybrid.


Rapid Early

Growth

Pitch Pocket

Sticker


7



Properties and Uses of

New Zealand

Radiata Pine

VOLUME ONE – WOOD PROPERTIES

Edited by J.A. Kininmonth & L.J. Whitehouse



8

Wood Quality… Impact on Product Yields, Grades and Value19.0TREE GROWTH AND TREE PHYSIOLOGY


Jan. Feb. Mar. Apr. May June July Aug. Sept. Oct. Nov. Dec.

Relativeactivity

Rootgrowth

DiametergrowthTop/crown

growth

Phenology of Tree Growth


9


• Terminal shoot and vigorous lastformed portions of the crownfoliage produce growth regulatinghormones (auxins) andphotosynthate.

• Lateral and downward trans-location of auxins to reach lower stem.

• In spring radial growth begins firstat the top of the tree and proceedsgradually downward = more EWand wider rings in upper crownregion near pith.

• Less EW and smaller rings at thebase where rings are far from pith.

• Transition to LW occurs first nearthe base, farthest from the sourceof auxin supply and proceedsupward.

• The destiny (and density) of anindividual fibre is thus determinedby its relative position; its distancefrom the active live crown regionand the time of its formation(season).


Allometry(allocation of photosynthetes)


10

Wood Quality… Impact on Product Yields, Grades and Value23.0WOOD STRUCTURE AND WOOD ANATOMY



11


Wood Anatomy


Earlywood

Latewood


12



western hemlock

true fir (Abies)

white spruce & Douglas-fir

western white pine

western redcedar

lodgepolepine


13


Douglas-fir western redcedar


resin ductsolid woodsubstance

air


14



latewood paperlatewood paper

earlywood paperearlywood paper


15

Wood Quality… Impact on Product Yields, Grades and Value33.0RELATIVE DENSITY OF WOOD

0.5

0.4

0.3

0.2

0.1

we

ste

rn r

ed

ce

da

r

su

ba

lpin

e f

ir

Inte

rio

r sp

ruce

Am

ab

ilis

fir

lod

ge

po

le p

ine

we

ste

rn h

em

lock

ye

llo

w-c

yp

ress

Do

ug

las-f

ir

we

ste

rn l

arc

h


Rela

tive

dens

ity

Global to Microscopic Viewof Density Distribution inBC Tree Species

Douglas-fir

LWEW

0.8

0.6

0.4

0.2

0

Geographic Tree-to-tree Pith-to-bark Within-annual-ring

western redcedar

LWEW

0.8

0.6

0.4

0.2

0


16


Douglas-firwood sample

Yellow-cypresswood sample

annual ring

annual ring

EW

EW

LW

LW

Density range0.25 – 0.85

Density range0.40 – 0.60

1.0

0.8

0.6

0.4

0.2

0.0

1.0

0.8

0.6

0.4

0.2

0.0

Wood Density Variation within Growth Rings


17

Wood Quality… Impact on Product Yields, Grades and Value36.0JUVENILE WOOD, CROWN-FORMED WOOD

(wood that is formed in the live crown)

8 20 35 85(years)

maturewood


Juvenile Wood (JW) andMature Wood (MW)

JW

MW

JW

MW


18



Douglas-firW. larchW. hemlock

Yellow-cypressLodgepole pineSitka spruce

Interior spruce

Subalpine fir

W. redcedar

Relative Density at BH ofRapidly Grown B.C. Woods

Age (years)

0.55

0.50

0.45

0.40

0.35

0.30

0.25

0.200 10 20 30 40 50 60

Juvenilewood

Maturewood

Transitionzone


19


Mature wood

Juvenile wood

Compression wood


Fibre length (mm)

Age (years)

4.0

3.5

3.0

2.5

2.0

1.5

0 10 20 30 40 50

Breast height

20% height

40% height

60% height

80% height

80%

60%

40%

20%

breastheight

Second Growth Douglas-fir


20


Ethanol:Benzene extractives (%)

24

18

12

6

00 10 100 1000

Number of rings from pith

Old growth

Second growth

Western Redcedar


Wood fibres from U.V.(ultraviolet) exposuredamage from sunlight.


21


71-year-old open-grownlodgepole pine.


Microfibril Angle

SecondaryWall

Primary WallMiddle Lamella


22

Wood Quality… Impact on Product Yields, Grades and Value46.0COMPRESSION WOOD

Wood Quality… Impact on Product Yields, Grades and Value47.0SHRINKAGE OF WOOD

Typical Shrinkage Values for ”Normal“ Wood


23


% Volumetric Shrinkage at 12% MC12

11

10

9

8

7

6

5

4

3.25 .30 .35 .40 .45 .50 .55

Relative Density

tamarack

western larchwestern hemlock

Amabilis fir

eastern white cedar

western redcedar yellow-cypress

Douglas-firsubalpine fir Jack pine

eastern white pine


Wood Quality… Impact on Product Yields, Grades and Value50.0CONCEPT OF “FREE” AND “BOUND” WATER


24


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Drying Stage: I II III

MoistureCondition:

Defects:

Above fibre saturationpoint (FSP) throughout:Drying begins with loss offree water from surfaces.

Stress-free Shell tries to shrink, createstension across surfaces,squeezes the core intocompression. Drying setsshell in oversized condition.

Core now trying to shrinkaway from oversized shell.Core develops tension, pulls shell into compression.

Surface is casehardened;core may honeycomb.

Surface may check; coremay collapse.

Defect-free

Growth ring boundarySurface checks(follow rays)

Shell below FSP (in tension)

Core above FSP (under compression)

Slight cup (due to board being flat-grained)

Core in tensionHoneycomb check, may be extension of reclosed surface checks.

Ray

Above FSP

Shell now below FSP, core still above FSP. Core moisture migratesoutward to shell.

Below FSP throughout,eventually reachesuniformly low EMC.

The Process of Wood Drying

Shell under compression

Drying Stage:

MoistureCondition:

StressCondition:

Defects:

Wood Quality… Impact on Product Yields, Grades and Value52.0SHRINKAGE OF WOOD Wood Quality… Impact on Product Yields, Grades and Value

53.0DOUGLAS-FIR TASK FORCE

Second Growth Douglas-fir Resource

1 Relative Density60 Trees

2 Juvenile Wood Transition24 Trees

6 Chemical Properties60 Trees

3 Longitudinal Shrinkage60 Trees

4 Fibre Length17 Trees

7 Log and Lumber Yields

8 Kiln Drying2 × 6

5 Strength and Stiffness2 × 4

9

20%

40%60%

80%

BH

299 Trees60 Trees

752 Logs

Chapter

Heartwood Treatability2 × 6

10 Density and ChemicalProperties 9 Trees 11 Unbleached Kraft Pulp

9 Trees 12 Refiner Mechanical Pulp9 Trees


25

Wood Quality… Impact on Product Yields, Grades and Value54.0DOUGLAS-FIR TASK FORCE



26


Size Premium

$300

$250

$200

$150

$100Random Lengths/Key Price IndicatorJanuary, 1992 Prices

S-P-F•RL•KD D-Fir•Green•RL

$/1000 fbm

Piece Size

Log

Value

Processing Cost

Do

llars

2 x 4

2 x 10

2 x 4

2 x 10


27



28


Cambial age (years)

0.55

0.50

0.45

0.40

0.35

0 5 10 15 20 25 30 35 40 45 50

Relative density

Juvenile wood Mature wood

Ring width (mm)8

7

6

5

4

3

2

6.35 mm

4.23 mm3.16 mm

Breast height20% height40% height60% height80% height

50-year-old Douglas-fir


0.42

0.41

0.40

0.42

100%

80%

60%

40%

20%

BH0.53

51%MW

(38.7 m)

49% juvenile w ood b y volume0.41

11

25

33

40

50

Years

Ladysmith42% Jw

20 20 cm0

100%

80%

60%

40%

20%

BH

12

23

33

42

50

Years

20Cassid y

46%

0

12

25

36

44

50

Years

20Campbell R

49%

020 cm 20 cm

6

13

20

27

33

Years

Cowic han L90% Jw

20 20 cm0

100%

80%

60%

40%

20%

BH

Lizar d L59%

Jor dan R59%

20 20 cm0

9

18

26

33

43

Years

20 20 cm0

14

25

34

41

45

Years

Juvenile Wood CylinderFirst 20 Years of Growth in 50-year-old Douglas-fir


29


Diameter, Taper and DensityDistribution in Douglas-fir

Ann ual ring relative density

0.44

0.36

0.430.41

20 10 0 10 20 (cm)Relative density distrib ution

d < 0.41

0.41 – 0.43

> 0.43

c 0.52

0.44

0.36

0.430.41

0.44

0.36

0.430.43

0.44

0.36

0.430.41

0.44

0.360 5 10 15 (cm)

Disk radius(cum ulative ring width)

a11 cm

11 yrs

24 cm

22 yrs

32 cm

30 yrs

38 cm

38 yrs

44 cm

45 yrs

20 10 0 10 20 (cm)

b80%

60%

40%

20%

BH

Average diskrelative density

Stem diameter and a ge0.40 0.44

0.430.41


Ladysmith(0.42)

Campbell R(0.43)

6

13

20

27

33

Years

Cowichan L(0.43)

Lizard L(0.43)

Jordan R(0.43)

14

25

34

41

45

Years100%

80%

60%

40%

20%

BH

20 200 20 200 20 100

9

18

26

33

43

Years

< 0.41 0.41 – 0.43 > 0.43

(cm)

11

25

33

40

50

Years100%

80%

60%

40%

20%

BH

Relative density

20 200 20 100

12

23

33

42

50

Years

Cassidy(0.45)

20 200

12

25

36

44

50

Years

(cm)

Relative Density Zones in Douglas-fir


30


Relative density

0.78

0.52

0.26

0

a

0 1 2 3 4 5 6

Average ring width (mm)

x = 0.41

Juvenile w ood 1–20 yrs

EW LW

30%

0 1 2 3 4 5 6

Average ring width (mm)

b

x = 0.47

Mature w ood

>20 yrs

EW LW

43%

Juvenile/Mature Wood Ring Profiles

0.78

0.52

0.26

0


0.52

0.48

0.44

0.40

0.36

0.320 25 50 75 100 125 150 175 200 225 250

Age at breast height (years)

Second gr owth

Relative density

Old gr owth

McGowan Cook

Stem-wood Relative Density


31


Conclusions:

2 These 50-year-old Douglas-fir trees, growingat 530 stems/ha, contained 50% juvenilewood and 50% mature wood.

2At all height levels, the first 20 years ofgrowth “defaulted” to juvenile wood because of wood density, fibre length, and longitudinal shrinkage.

2 Juvenile wood is not useless wood.

2 Larger knots permitted in wider widths.

2Challenge: find optimum between tree sizeand branch size at rotation age to maximizevalue, keeping future trends in mind.

commercial forestry has to be profitable

• Other non-woody pressures on the land base – social forestry

$/ha/yr

Wood Quality… Impact on Product Yields, Grades and Value65.0LODGEPOLE PINE TASK FORCE

Average Dimensions of Small, Medium andLarge Diameter Lodgepole Pine Task Force Trees

25

20

15

10

5

0

3020100

DBH (cm) 37.0 37.6 35.7 27.5 17.8 17.5Age (yrs) 71.0 91.0 85.0 121.0 96.0 95.0Stems/ha 1 600 900 1300 1800 2300

Density BH 0.36 0.37 0.38 0.41 0.43 0.46Stem Density 0.37 0.37 0.38 0.39 0.40 ~0.43Stem Volume 0.81 1.00 0.92 0.47 0.18 -

Open-grown Alta. B.C. G H I

DB

H (c

m)

Tree

Hei

ght (

m)

2x10

2x4

100%

51%

44% 37% 35% Base of live crown (%)


32

Average Disk Density atFive Sampling Heights

80%

60%

40%

20%

0.34 0.36 0.38 0.40 0.42 0.44 0.46

spec

ies

aver

age

0.41

MarlboroAverage of six largediameter sitesBingay CreekMedium (Fording Mtn.)Small (Fording Mtn.)Medium (Sulpher) &Small (Sulpher)Control

BH

Sam

plin

g H

eigh

t (%

)

Disk Relative Density

51%44%

35%

crown


Pith-to-bark Wood Density and Tree-sizeTrends as a Function of Stand Density

Pith-to-bark wood density

0.45

0.40

0.35

0 2.5 5 7.5 10 12.5 15 17.5 20Disk radius (cm)

16 cm, 95 yrs at BH; 2300 live stems/ha


40 cm, 71 yrs at BH; open-grown tree


28 cm, 121 yrs at BH;1300 live stems/ha

Resource-average basic relativedensity for lodgepolepine 0.41


33


Second GrowthLodgepole PineDensity Distribution

Site G

<.38

.38 - .41

>.41

25 20 15 10 5 0 5 10 15 20 25Stem radius (cm)

28

26

24

22

20

18

16

14

12

10

8

6

4

2

0

Tree

hei

ght (

m)

25 20 15 10 5 0 5 10 15 20 25Stem radius (cm)

28

26

24

22

20

18

16

14

12

10

8

6

4

2

0

Sites A-F

Tree

hei

ght (

m)

25 20 15 10 5 0 5 10 15 20 25Stem radius (cm)

28

26

24

22

20

18

16

14

12

10

8

6

4

2

0

Site H

Tree

hei

ght (

m)


34


400

300

200

100

0

100

90

80

70

60

50

40

30

20

10

0

LumberVolume (%)

10 15 20 25 30 35 40 45 50Top Diameter Class (cm)

10 15 20 25 30 35 40 45 50Top Diameter Class (cm)

LRF (fbm/m3)

2x42x62x82x10



35


Structural Lumber Yields by Visual Grading

100

90

80

70

60

50

40

30

20

10

0700 1100 1900

% FBM

Stand Density (stems/ha)

RejectEcon.No. 3No. 2No. 1SS


Door, Window and Furniture-GradeLumber Yields by Visual Grading

100

90

80

70

60

50

40

30

20

10

0700 1100 1900

% FBM

Stand Density (stems/ha)

Reject6th5th4th


36

MSR SummaryUses of MSR Lumber

2 Primarily for roof trusses, I-joists, laminatingstock for glulam

2 Parallel chord floor trusses – new market(ease of handling, longer spans, ready openings for wiring, plumbing and ductwork)

Advantages of MSR Lumber• better consistency because of E rating

(more uniform “links”)• quality control in the plant – none with

visually graded• lumber can be cut from small logs (no need

for very wide widths)• reduced variability = reliability and exactness• reduced waste (2% vs 10%)• uniformity across “species boundaries”

(fewer grades)• Profit (marketability)

Wood Quality… Impact on Product Yields, Grades and Value74.0MACHINE STRESS RATED (MSR) LUMBER

MSR Grading System


Strength of wood is the resistance to forces deforming it.

2 There are still other things besides relativedensity that affect the strength of wood.

2 These include knots, slope of grain,compression wood, the relative amounts ofearlywood and latewood, moisture content,temperature (above 65˚C), and fibril angle (thepart of the tree, near the pith, or farther outfrom which the piece was cut).

2A few basic terms in wood mechanics:

force: push, pull and shearstress: force per unit area (psi)strain: unit deformationstiffness (elasticity): stress/straincreep: continuously stressed in

bending,“flow”,“sag”fatigue: loss in wood property due to

repeated force application (bending backand forth, 1/3 max. stress, 30,000,000 times)


37


Machine-stress rated lumber yields

Freq

uenc

y (%

of p

iece

s)

80

70

60

50

40

30

20

10

0Reject 1650f 2100f 2400f

MSR Grade

Distribution of MSR Grades for 2x4‘s by Stand Density

700 s/ha1100 s/ha1900 s/ha

Distribution of MSR Grades for 2x6‘s by Stand Density

80

70

60

50

40

30

20

10

0Reject 1650f 2100f 2400f

700 s/ha1100 s/ha1900 s/ha


38

Western SPF KD Std&BtrRandom Lengths – 2x4

Weeks of the Year

400

350

300

250

200

150

US Funds –FOB Mill

4 8 12 16 20 24 28 32 36 40 44 48 52

As reported by Madison’s Canadian Lumber Reporter – May 24, 1996

1996 1995 1991

1991

1995

1996


MSR Lumber—Kiln Dried—8'/20'2x4 SPF 2x6 SPF

1650f $490 {450} $440 {400}1800f 495 {455} n/a n/a2100f 495 {460} 465 {425}2400f 520 {480} 480 {440}

*Prices are in U.S. funds, F.O.B. ChicagoPrices in () are f.o.b. Vancouver

As reported by Madison‘s Canadian Lumber Reporter


39

Wood Quality… Impact on Product Yields, Grades and Value78.0LODGEPOLE PINE CONFIRMATION STUDY

0.50

0.48

0.46

0.44

0.42

0.40

0.38

0.36

0.34

0.32

0.30

0.50

0.48

0.46

0.44

0.42

0.40

0.38

0.36

0.34

0.32

0.30

20 25 30 35 40 25 30 35 40 45 25 30 35 40 25 30 35 40 45 25 30 35 40 45 25 30 35 40 45D.b.h. Class (cm)

SS SS JC WE LI EL ML SS JCWE LI FL ML SS JCWE LI EL ML SS JCWE LI EL ML JC LI EL ML

Location

D.b.h. Class (cm)20 25 30 35 40 45

Breast HeightRelative Density

Sulphur Springs (MS) = SS Wells (ESSF) = WE Elbow Lake (ICH) = ELJamieson Creek (MS) = JC Likely (IDF) = LI Modeste Lake (SBS) = ML


40

Wood Quality… Impact on Product Yields, Grades and Value79.0WESTERN HEMLOCK BASIC WOOD PROPERTIES

Rela

tive

dens

ity

Hea

rtw

ood/

Sapw

ood/

M.C

.

Com

pres

sion

woo

d

Spir

al g

rain

Bro

wn

stai

n

Long

itudi

nal s

hrin

kage

90%

80%

70%

60%

50%

40%

30%

20%10%

Breast ht.70 cm

Stump ht.

Sampling plan for basic wood properties characterizationof second-growth western hemlock.


41


Oldgrowth

speciesaverage

Second-growth Western HemlockDisk Densities at 12 Heights for Five Sites

0.50

0.48

0.46

0.44

0.42

0.40

0.38

0 10 20 30 40 50 60 70 80 90 100

Average RelativeDensity

% of Tree Height

Port Mellon 840 stems/haPort Hardy 650 stems/haLake Cowichan 440 stems/haPort Hardy M22 1000 stems/haPort Renfrew 986 stems/ha


Second Growth Hemlock –Total Stemwood Density Distribution

0.50

0.45

0.40

0.35Port Mellon Port Hardy Lake Cowichan Port Hardy M22 Port Renfrew

Total StemDensity

Site


42


Pith-to-Bark Ring Width Profiles

0.5

0.4

0.3

0.2

0.1

0.00 20 40 60 80 100

Ring Width (cm)

Cambial Age

Port MellonPort HardyLake CowichanPort Hardy M22Port Renfrew

Pith-to-Bark Density Profiles

0.54

0.52

0.50

0.48

0.46

0.44

0.42

0.40

0.38

0.360 20 40 60 80 100

AverageRelative Density

Cambial Age

Port MellonPort HardyLake CowichanPort Hardy M22Port Renfrew

0.423 – medium grain

0.316 – fine grain


Western Hemlock Port HardySummary of 13 Trees

0.6

0.5

0.4

0.30 20 40 60 80 100

RelativeDensity

Cambial Age

Stump HtBreast Ht20% Ht40% Ht60% Ht80% Ht

0.6

0.5

0.4

0.30 20 40 60 80 100

RelativeDensity

Cambial Age

Stump HtBreast Ht20% Ht40% Ht60% Ht80% Ht


43


Lake CowichanSummary of 13 trees (450 stems/ha)

100%

90%

80%

70%

60%

50%

40%

30%

20%

10%BH70 cmstump

100%

90%

80%

70%

60%

50%

40%

30%

20%

10%BH70 cmstump

45

40

35

30

25

20

15

10

5

030 20 10 0 10 20 30

Stem Radius (cm) Area (cm2)

600 400 200 0 200 400 600

Relative Density Zone: <0.40 0.40 – 0.43 >0.43 minimum density

42.3 m 42.3 m

Tree

Hei

ght (

m)


Port Hardy M22Summary of 13 trees (1000 stems/ha)

100%

90%

80%

70%

60%

50%

40%

30%

20%

10%BH70 cmstump

100%

90%

80%

70%

60%

50%

40%

30%

20%

10%BH70 cmstump

40

35

30

25

20

15

10

5

030 20 10 0 10 20 30

Stem Radius (cm) Area (cm2)

600 400 200 0 200 400 600

Relative Density Zone: <0.40 0.40 – 0.43 >0.43 minimum density

39.7 m 39.7 m

Tree

Hei

ght (

m)


44

Average Tree Stem Profiles and Density Distributions(summary of 13 trees per site at age 60 superimposed onto 90 year old trees)

Port Mellon840 stems/ha

Port Hardy650 stems/ha

Lake Cowichan440 stems/ha

Port Hardy M221000 stems/ha

Port Renfrew986 stems/ha

Stem Radius (cm)

Area (cm2)

Relative Density Zones: < 0.40 0.40 – 0.43 > 0.43

50454035302520151050

50454035302520151050

Tree

Hei

ght (

m)


45


Western Hemlock Port Hardy

0.6

0.5

0.4

0.30 20 40 60 80 100

Total StemDensity

Cambial Age


46


Geographic Tree-to-tree Pith-to-bark Within-annual-ring Microscope

1.0

0.8

0.6

0.4

0.2

0

Global to Microscopic Viewof Density Distribution inWestern Hemlock

a b c d e

LWEW

lll

Solid CellWall Relative

Density 1.1

1.0

0.8

0.6

0.4

0.2

0


Western Hemlock Log Grade Old-growth Second-growth

small Ø D log length $ 10,000 $ 4,000

12 – 36 in. H 16 – 24' 12,000 8,000

15 – 36 in. I 12 – 14' 12,000 15,000

4 – 11 in. J 16 – 24' 5,000 20,0004 – 14 in. X 8 – 14' 6,000 4,000

4 – 36 in. Y < 8' 5,000 4,000

Total $ 50,000 $ 55,000

• Stand volume in second-growth 150 – 200m3

higher than in old-growth

15 – 36 in. 8 – 10'

WFPL – North Vancouver Island


47

Wood Quality… Impact on Product Yields, Grades and Value90.0COMPOSITES, SUMMARY AND CONCLUSIONS



48

Geographic Tree-to-tree Pith-to-bark Within-annual-ring Microscope

1.0

0.8

0.6

0.4

0.2

0

Solid CellWall Relative

Density 1.1

Global to Microscopic Viewof Density Distribution inBC Tree Species

a b c d e

lllLWEW

Western HemlockLodgepole PineDouglas-firWestern RedcedarYellow Cypress

1.0

0.8

0.6

0.4

0.2

0


49


…Tree, Log, Lumber and Fibre Characteristics


Wood Quality is Related to Measurable Stand…


50

Wo

od

Qu

ality

…Im

pac

t o

n P

rod

uct

Yie

lds,

Gra

des

an

d V

alu

e95

.0C

OM

PO

SIT

ES

, SU

MM

AR

Y A

ND

CO

NC

LUS

ION

S

Documents

Wood Quality… · RELATIVE DENSITY OF WOOD 33.0 0.5 0.4 0.3 0.2 0.1 western redcedar subalpine fir Interior spruce Amabilis fir lodgepole pine western hemlock yellow-cypress Douglas-fir