Relationships between tree architecture
and wood physical properties of
Tectona grandis(Teak)
Kodjo TONDJO1,2, Loïc BRANCHERIAU1 , Sylvie SABATIER1 , Adzo Dzifa
KOKUTSE2 , Acardius AKOSSOU3 , Thierry FOURCAUD1 ,Kouami KOKOU2
1
UMR AMAP CIRAD Montpellier 2, France
2 LBEV , Université de Lomé, TOGO
3Université de Parakou, Faculté d’Agronomie, Cotonou, Bénin
Relationships between Architecture and Wood properties in Teak. IUFRO Nancy, 2013, Tondjo
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Teak is the major fast-growing
species planted in Togo:
→ Largest plantation area
→Exceptional wood quality
(sustainability, resistance, etc.)
Teak wood
Main objective:
better understanding of the impact
of silvicultural practices and
seedlings provenance on wood
quality
Relationships between Architecture and Wood properties in Teak. IUFRO Nancy, 2013, Tondjo
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Teak flowering
Hypothesis to test:
The expression of flowering
influences the height of the
commercial log and the wood
physical properties
The expression of flowering is studied
through 2 factors: the thinning
practice and the provenance
Relationships between Architecture and Wood properties in Teak. IUFRO Nancy, 2013, Tondjo
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* 3 Stands (same bio-climatic
conditions):
1 thinning practice, 2 provenances
* Tree age is between 10 and 11years
* Average annual rainfall: 1100mm to
1400mm
Experimental design
Thinning pratices
Thinning
Provenances
Without
thinning
Togo teak
20
20
Tanzanian
Teak
20
0
Relationships between Architecture and Wood properties in Teak. IUFRO Nancy, 2013, Tondjo
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Individual scale (main tree stem)
* Inter-annual limits (identification of
growth units=GU)
* Location of the first flowering
* Number of floriferous growth unit
Growth Unit (GU) scale
* Length
* Base Diameter
Inter-annual
limits
Terminal
inflorescence
Floriferous
GU
Relationships between Architecture and Wood properties in Teak. IUFRO Nancy, 2013, Tondjo
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GU4
GU3
GU2
GU1
Disk
3cm of width
* Removing disks (GU1, GU2, GU4)
*Cuttingradialsegments(180=20treesx3plotsx3
segments)
* Scanning segments to measure ring width
* Use NIRS=Near Infa-Red Spectroscopy
( Bertrand and Dufour, 2000): fast method to
measure wood properties(Basic-density=BD,
Modulus of elasticity=MOE)
* Calibration of NIRS 143 cubes(15x15x45mm)
were cut from 44 segments as reference
samples
Relationships between Architecture and Wood properties in Teak. IUFRO Nancy, 2013, Tondjo
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Basic density
MOE
*Statistical models
Cross-validation in 10 random segments
Basic density( R²=0.84, RMSEP=25
kg/m3)
MOE (R²=0.87, RMSEP=1573 Mpa)
*Predictions of NIRS
180 radial strips each 5 mm intervals
along the radius
* Use predictives data for analyses
Relationships between Architecture and Wood properties in Teak. IUFRO Nancy, 2013, Tondjo
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20
15
5
10
LC
Rings width (cm)
0
vegetative
growth unit
1
floriferous
growth unit
Floraison
The average ring width was significantly lower for
floriferous GU compared to the vegetative GU
Relationships between Architecture and Wood properties in Teak. IUFRO Nancy, 2013, Tondjo
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Modulus elasticity
(Mpa)
Basic-density
Vegetative
growth unit
Floriferous
growth unit
Vegetative
growth unit
Floriferous
growth unit
Significantly higher average for floriferous GU compared
to the vegetative GU average
Relationships between Architecture and Wood properties in Teak. IUFRO Nancy, 2013, Tondjo
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600
Togo
Tanzania
550
Basicdensity
650
700
Variation of BD and ring width depending cambial age and provenance
recente.1
ancienne.2
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Cambial age (from pith to bark, year 2002 to 2011)
5
0
Ring
width
10
15
20
ancienne.1
ancienne.1
recente.1
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CA has an influence on basic-density and rings width
but no effect of provenance
Relationships between Architecture and Wood properties in Teak. IUFRO Nancy, 2013, Tondjo
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Number of successive
inflorescences on the main stem
Significant effect of
thinning(**):
Thinning delays flowering
Tree density influences the
number of successive
floriferous GU (log height)
Thinning
Without
thinning
Relationships between Architecture and Wood properties in Teak. IUFRO Nancy, 2013, Tondjo
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15
Number of successive
inflorescences on the main stem
10
0
Provenance does not seem
to influence the flowering
5
No clear difference was
found for the 2 provenances
0
1
2
ancienne
Togo
recente
Provenance
Tanzania
Relationships between Architecture and Wood properties in Teak. IUFRO Nancy, 2013, Tondjo
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Thinning influences the expression of flowering but no
effect of provenance
Strong link between flowering and production (ring width)
and wood quality (BD and MOE)
The biomass allocation to flowering decreases wood
production and increases wood properties
Ring width, the MOE and BD vary significantly with CA but
regardless of the provenance and the thinning
Relationships between Architecture and Wood properties in Teak. IUFRO Nancy, 2013, Tondjo
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YES hypothesis is valid (in the studied conditions) for BD,
MOE and rings width
Architectural analysis can be used to estimate Wood
properties
This work will allow us to introduce the basic density model
wood in the structure-function model (Greenlab) in order to
connect the ontogeny effect in the production and wood
quality
Relationships between Architecture and Wood properties in Teak. IUFRO Nancy, 2013, Tondjo
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Thank you for your attention
Relationships between Architecture and Wood properties in Teak. IUFRO Nancy, 2013, Tondjo
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