Australian Greenhouse Office 8 Page Line Correction (Delete = delete this line) (Replace = replace existing line with the following) Scientific Name Sub-Species Name Notes Confidence in data (H,M.L) Data reference Tr ee age (mature/age) Common Names Number of trees tested Basic Density (kg/m 3 ) 95% Probability Range for Mean Estimated Basic Density from Air -dr y (12%) MC Estimated 95% Probability Range for Mean Number of trees tested Air -dr y density (12% MC) before reconditioning (g/cm3) 95% Probability Range for Mean Number of trees tested Air -dr y density (12% MC) after reconditioning (g/cm3) 95% Probability Range for Mean Green density (g/cm 3 ) SD Green Moisture Content (%) SD Area W eighted Density Data on BD & tree height Comprehensive Species list NSW Victoria Queensland South Australia Tasmania W estern Australia (Ref. within W A ) Northern T e rritor y Australian Capital T e rritor y Australia Abundance (1,2,3,4,5) See Appendix 2 National Carbon Accounting System Technical Report 9
National Carbon Accounting System Technical Report 10 Australian Greenhouse Office 10 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Title Shrinkage and density of
Australian and other South-west
Shrinkage and density of
Australian and other South-east
The anatomy of Eucalypt woods
Australian timbers: Volume two
Queensland Timbers: Their
nomenclature, density and lyctid
The mechanical properties of
174 Australian timbers
The mechanical properties of
Australian, New Guinea and
Goldfields timber: Research report
An assessment of the kraft
pulping properties of residual
mature eucalypt roundwood from
Kraft pulping of East Gippsland
Density and shrinkage of four low
rainfall plantation grown eucalypts
Wood densities for fifty-two
Australian tree species
Wood in Australia: Types,
properties and uses
Where to shoot your pilodyn:
Within tree variation in basic
density in plantations of
Eucalyptus globulus and E. nitens in Tasmania
Notes Division of Forest Products
Technological Paper No 13.
Division of Building Research
Technical Papers (Second Series)
Forest Products Laboratory:
Division of Applied Chemistry
Technological Paper No. 66
Technical Pamphlet No.2
Division of Forest Products
Technological Paper No. 25
Bulletin No. 279
Department of Commerce and Trade;
Goldfields Esperance Development
Commission; Department of
Conservartion and Land
Management; Goldfields Specialty
Timber Industry Group Inc. and
Curtin University, Kalgoorlie Campus
Appita Vol. 44 No. 4
Appita Vol. 44 No. 6
CSIRO Technical Report
New Forests 15: 205-221
McGraw – Hill Book
Author Kingston R.S.T. and
Cause M.L., Rudder
E.J. and Kynaston W.T.
Bolza E. and Kloot N.H.
Stewart A.M. and
Siemon G.R. and
Mamers H., Balodis V.,
Garland C.P., Langfors
N.G., Menz D.N.J. and
Mamers H., Balodis V.,
Garland C.P., Langfors
N.G. and Menz D.N.J.
Raymond C.A. and
Data reference number
WOODY DENSITY PHASE 1 - STATE OF KNOWLEDGE Jugo Ilic, Doug Boland, Maurice McDonald Geoff Downes and Philip Blakemore CSIRO Forestry and Forest Products National Carbon Accounting System Technical Report No. 18 October 2000 The Australian Greenhouse Office is the lead Commonwealth agency on greenhouse matters.
EXECUTIVE SUMMARY 1. OBJECTIVES The Australian Greenhouse Office (AGO) contracted
CSIRO Forestry and Forest Products (FFP) to
examine the wood density of Australian tree species
for use in the National Carbon Accounting System.
This consultancy will be undertaken in two stages
with this report incorporating the outputs from the
first stage. The objectives of the first stage were:
to list the available wood density
information for Australian tree species;
to provide an indication of species
distribution and representation;
to list the Australian tree species where
density is not available; and
to provide a methodology for evaluating
The second stage of the project will include the
determination of wood densities of tree species
where density information is lacking. Obviously
this second stage of the project is reliant on the
outcomes of the first stage, and the species to be
sampled will be agreed with the AGO.
2. KEY OUTCOMES The major outcomes of the first stage of the study
Basic density data have been provided for
approximately 590 Australian tree species
and these are presented in Appendix 1. The
data was derived from 14 different
published sources with varying levels of
reliability in the values, ranging from low to
high. Only published sources that quoted
variation of wood density were denoted as
Descriptive and functional methodologies
have been presented for the direct
determination of wood density by
gravimetric and maximum moisture
methods, which can be used to obtain
whole tree stem estimates of wood density.
A methodology has also been presented for
the indirect determination of wood density
using pin penetration (pilodyn), which
needs to be calibrated using direct
determination of wood density. The
indirect method provides less accuracy for
individual trees, but does allow many
estimates of wood density to be taken
quickly, and it can be potentially useful for
ranking trees into broad density classes
within sites. Within these broad density
classes the class means can be used for
comparing site densities.
Species distribution maps for native
hardwood species that are harvested
commercially (10 species), and for major
plantation species, are provided. This
addresses the item "distribution and
representation in the Australian landscape
of key species" in the Terms of Reference for
No attempt was made to estimate average wood
densities of whole trees or forest structural classes
or regions of Australia. Where tree species quoted
95% probability ranges for their density, these data
are taken to represent whole tree variation
(Kingston and Risdon 1961).
Most States appear to have good statistics for the
main commercial species harvested. Information
available on the minor species being harvested is
less well documented. The report does not include
data on tree species removed through clearing on
private land due to a lack of comprehensive
information. This particularly applies to the large
areas currently being cleared in Queensland.
National Carbon Accounting System Technical Report iii
3. RECOMMENDATIONS The data gaps identified in this report should be
addressed in the second stage of this project. The
second stage of the project should proceed to:
Categorise forest types by structure or
Identify 5-10 key species within each forest
Determine wood density for each of those
key species, where the data is missing.
Australian Greenhouse Office iv
TABLE OF CONTENTS Page No.
1.1 Overall Terms of Reference
Basic Density and why it is important
2.1 Determination of Basic Density
2.2 Calculation of basic density Water-immersion
2.2.1 Equipment and Procedure
2.2.2 Procedure for water displacement determinations
2.3 Maximum saturation
2.4 Nondestructive estimation using the Pilodyn
2.4.1 Calibration and use of the Pilodyn
Estimating wood density of whole trees (Whole tree correlations)
Necessary site data
Obtaining the sample
Sampling using 12 mm increment cores
How many to sample
Where to sample
How to take an increment core sample
3.10 Sample coding
3.11 Steps in non-destructive sampling using a motorised corer
3.12 Sample storage
3.13 Time required for field sampling
3.14 Building the calibration
3.15 Explanatory notes
What do we need to know (Priority)?
List of taxa with available density data
References for available density data
List of taxa for which no density data is available
Australian Native Forest Tree Species Harvested Commercially
(Terms of reference relevant to this part of the consultancy)
A list of common tree species.
National Carbon Accounting System Technical Report v
2.2 Species commercially harvested in each State
2.3 Plantation eucalypts
2.4 Forest biomass inventory: through the incorporation of wood density values for
3.1 Natural and commercial species
3.2 Commercial hardwood plantations
Species distribution maps
LIST OF TABLES Appendix 2
Table 1. List of common species in Australia (supplied by Mr. Arthur Court). Column 1 lists
those common species in the “Australia’s State of Forest Report” whilst Columns 2-6
list those species commonly harvested in State Forests in Australia.
Table 2. Indigenous hardwood and Callitris timber species commonly harvested in NSW including
volumes and proportion of the total harvest for 1998/99.
Table 3. Indigenous hardwood timber species harvested in WA from state forests and private property.
Table 4. Indigenous hardwood timber species harvested from State Forests in Victoria.
Table 5. Indigenous hardwood/softwood timber species harvested from State Forests in Tasmania
in 1998/99. (Information from Mr Michael Wood.)
Table 6a. Indigenous timber species harvested from State Forests in Queensland in 1998/99. Includes
Hardwoods and Callitris. (Information from Mr C. Bragg).
Table 6b. Sawlog yields from crown forests in Queensland from 1 July 1999 - 30 June 2000.
Table 7. Areas planted to hardwood plantations by State (data from BRS, March 2000).
Table 8. Areas planted by tree species up till 1994 and estimates of proportion of species planted
in 1994 and 2000.
LIST OF FIGURES Figure 1. Example of a temperature controlled oven for drying sections.
Figure 2. Diagram of water displacement method for measuring volume.
Figure 3. Pilodyn tester used for estimating basic density in a eucalypt log.
Australian Greenhouse Office vi
1. INTRODUCTION 1.1 OVERALL TERMS OF REFERENCE. The Australian Greenhouse Office (AGO) has
contracted the CSIRO Division of Forestry and
Forest Products to review the availability of wood
density information for common Australian tree
The first stage of the consultancy requires a review
of available information. This review report will
A list of tree species where wood densities
A list of tree species where wood densities
are not available;
The distribution and representation in the
Australian landscape of key species. This
has been interpreted to mean the
production of species distribution maps for
the key species being harvested (about 10
Specific analytical methods by which any
further derivation of wood densities should
The second stage (which should be separately
costed) should contain a proposed fee structure for
the determination of wood densities (on a per
species/sample or equivalent basis). The species to
be sampled will be agreed with the Office on
completion of the first stage report. The final report
for this second stage will contain the wood densities
for each species sampled.
To complete the second stage of the work greater
consideration will have to be given to determining
average density values for particular forest
"categories" (see Appendix 2; Methods and
Conclusion). The task then is to list the 5-10 key
species for each category and make sure that wood
density values are available for each of those key
2. BASIC DENSITY AND WHY IT IS IMPORTANT An estimate of the amount of carbon locked up in
forested land including native forests and
plantations is necessary for accounting of net carbon
emissions within Australia. A major component of
carbon storage is in the woody stem and an estimate
of the total carbon can be gained from a knowledge
of the wood basic density comprising the stem and
the total volume it occupies.
Wood density is a complex physical property since
the tissue is made up of differing proportions of
cells of variable size and chemical composition.
These variations depend on the species and its
interactions with the environment. Generally
density from mature trees is higher than that from
young trees. Density varies in trees from pith to
bark and from base to apex and it is affected by tree
age. Similarly wood density of branches is likely to
vary, but little information is available. To
determine the total amount of carbon locked up in
woody tissue, a knowledge of both the volume and
the density of that tissue is required.
The majority of studies looking at density variation
have been on commercial timbers, predominantly
plantation species. Little or no data are available on
patterns of variation in non-commercial species.
The studies on plantation species have indicated the
following important factors.
Wood density varies from base to apex. The
pattern appears to differ between softwoods
(radiata pine) and hardwoods (eucalypts).
Density has a cylindrical symmetry in
softwoods (see description in Downes et al.
1997) resulting in a reduction in density
with height. In eucalypts the pattern
appears to be more conical with the
interaction between the radial and
longitudinal variation allowing density to
remain constant or increase with height.
Usually based on studies with plantation
species the general pattern appears to be a
National Carbon Accounting System Technical Report 1
gradual increase with height. Many very
useful references to studies on density
variation of eucalypts are given in Hillis
and Brown (1984).
Wood density in trees appears to be
controlled more by a combination of
environmental factors than by its radial
growth rate. Rainfall affects density
variation. Application of fertiliser results in
decreases in average wood density whereas
the effects of thinning are variable (Hillis
and Brown 1984).
Annual ring average density generally
increases from pith to bark in all species
(softwood and hardwood) with the rate and
pattern of increase dependent upon species
and growth pattern. Growth pattern
reflects the proportions of the ring that is
produced at different times of the year
which controls the average density of the
ring. In general, increasing growth rate will
result in more wood production in spring.
This wood tends to have a lower density,
and therefore faster growth rate generally
results in lower annual ring density.
Rainfall appears to have a dominant effect.
It is clear that the method of sampling can affect the
data obtained and its interpretation. For sampling
to be most effective, there needs to be a clear
understanding of why the samples are being taken,
and how they are going to be analysed. The choice
of methods for sampling and analysis of wood
properties should consider the need to interpret the
resultant data within the context of existing
scientific literature (Downes et al. 1997).
2.1 DETERMINATION OF BASIC DENSITY Basic density is expressed as the ratio of the weight
of the oven dry sample to its green volume. The
physical units used for the quantities are usually
(kg) for the dry mass, and (m
) for the wood
The measurement of wood density has traditionally
involved the collection of wood samples (e.g. disks
or increment cores) and subsequent laboratory
determinations of weights and volumes.
The water-immersion method and the maximum-
saturation method are two direct methods for
determining the basic density. Both methods
require a specific specimen to be measured. The
water-displacement method requires the evaluation
of weights and volumes whereas the maximum
moisture method only requires the evaluation of
specimen weights, but the green sample must be
initially fully water saturated. However, by
necessity both direct methods are partially
destructive in that a sample needs to be removed
from a tree for evaluation.
In another approach, a pilodyn wood tester
originally designed for assessing soft rot in wooden
poles can be used to obtain an indirect measure of
wood density. The instrument fires a blunt, spring-
loaded steel pin into the wood with known energy.
The depth of pin penetration is noted from a scale
on the body of the instrument. Depth of pin
penetration has been shown to be negatively
correlated with wood basic density for several
species of gymnosperms as well as angiosperms
(Cown 1981; Moura et al. 1987; Ilic and Bennett
2000). Trials with the pilodyn have shown to be
rapid and less liable to operator bias. The accuracy
is less for individual trees. The best potential use of
the instrument would be for ranking trees into
broad density classes within sites, and then use class
means for comparing site densities.