Universiti Putra MalaysiaSerdang, Selangor

Evaluation of Selected Physical and Mechanical Properties of Multiple Leader Acacia crassicarpa

A.Cunn.Ex.Benth and Acacia mangium Willd.

Evaluation of Selected Physical and Mechanical Properties of Multiple Leader Acacia crassicarpa

A.Cunn.Ex.Benth and Acacia mangium Willd.

Nor Aini Ab. ShukorNor Aini Ab. Shukor, Paridah Md. Tahir, Mohd. Faisal Jaafar , Paridah Md. Tahir, Mohd. Faisal Jaafar and Zainal Abidin Ismailand Zainal Abidin Ismail

INTROP/Faculty of ForestryINTROP/Faculty of Forestry Universiti Putra MalaysiaUniversiti Putra Malaysia 43400 Serdang, Selangor, 43400 Serdang, Selangor, MALAYSIA.MALAYSIA.Tel:6-03-89467186Tel:6-03-89467186

anishukor@yahoo.comanishukor@yahoo.com

INTRODUCTION• Forest tree plantation in Forest tree plantation in

tropics - exotic species. e.g. tropics - exotic species. e.g. pines and acaciaspines and acacias..

• Species trial results - useful Species trial results - useful information oninformation on: :

(a) performance(a) performance (b) adaptability(b) adaptability (c) species-site interaction…(c) species-site interaction…

BUTBUT• Required research to Required research to

understandunderstand, physiology, , physiology, genetic and wood properties.genetic and wood properties.

• Extent of Extent of AcaciaAcacia plantation in plantation in Asia – reviewAsia – review - Turnbull (1998); - Turnbull (1998);

•Many national and international provenance Many national and international provenance trials of trials of A. mangiumA. mangium and and A. crassicarpa A. crassicarpa conductedconducted – – different regions. e.g. China,different regions. e.g. China, IndonesiaIndonesia, , Malaysia, Thailand, and Vietnam. Malaysia, Thailand, and Vietnam.

•Results of introductions and genetic Results of introductions and genetic improvement especially in Malaysia and improvement especially in Malaysia and Thailand revealed some impediments and Thailand revealed some impediments and limitations in :limitations in :

(a) (a) growthgrowth - incidence of heartrot - incidence of heartrot (b) (b) Tree formTree form - develop multiple trunk and - develop multiple trunk and epicormic epicormic

branching/multiple leader branching/multiple leader (ML) (ML) formation formation

•ML – most limiting factor for log production of ML – most limiting factor for log production of desirable size – 15 years rotationdesirable size – 15 years rotation•ML – having more than 1 leader/stem from ML – having more than 1 leader/stem from the basethe base

Figure 1: Various classes of ML formation

ML class 1 ML class 4ML class 2 ML class 3

• Actual factors causing and variation of ML - not known.

• It may be due to genetics and site environmental conditions (Srivastava,1993).

• Others related it to: (a) cultural practices (b) genetic variation within genotypes and families• Standard sivilcultural practice in Malaysia

of ML - singling i.e. retaining one stem per tree and cutting the rest.

• Done as early as 4 - 6 months after out planting - before formation of heartwood.

• Formation of ML is undesirable – lower the quality of timber – no report on quality of wood properties of ML sources.

• Singled wood usually not utilized or as alternative raw material in composite manufacturing (Kong, 1998).

OBJECTIVESOBJECTIVES

• To evaluate selected mechanical and physical properties of the multiple leadered trees from different genotypes of Acacia crassicarpa and Acacia mangium.

• To evaluate selected mechanical and physical properties of the multiple leadered trees from different genotypes of Acacia crassicarpa and Acacia mangium.

MATERIALS AND METHODSMATERIALS AND METHODS

Seeds of Seeds of A. A. crassicarpacrassicarpa

Wood specimens for 5 yr-old of 2 Wood specimens for 5 yr-old of 2 species; species;

i) i) A. mangiumA. mangium ii) ii) A. A. crassicarpacrassicarpa involving : involving :

1. 1. Provenances Provenances from 2 regions i.efrom 2 regions i.e a) 4 from Queensland (a) 4 from Queensland (QLDQLD) )

i) i) Claudie River, ii) Chillie Beach, iii) Captain Billy road, iv) Russel Gap & CK

b) 3 from Papua New Guinea (b) 3 from Papua New Guinea (PNGPNG))i) i) Bensbach WP, ii) ii) Bimadebu WP iii) SW of Boset WPANDAND

2. 2. ML classesML classes i.e i.e a) ML2 (with two leaders) a) ML2 (with two leaders) b) ML3 (with more than two leaders).b) ML3 (with more than two leaders).

Seeds of Seeds of A. mangiumA. mangium

PNG

Figure 2 : Selected provenances used in this study.

QLD

•Bimadebum WP•Bensbach WP

•Captain Billy road

•Russel Gap & CK•Claudie River

•Chillie Beach

•SW of Boset WP

Table 1: Provenances (genotypes) of A. crassicarpa and A. mangium

Multiple Leader

Region ProvenanceLatitude

(°S)Longitude

(°E)Altitude

No. of Trees

No. of Samples

2

PNGBensbach WP 05° 03’ 141° 17’ 25m 4 10

Bimadebum WP 03° 08’ 142° 03’ 40m 3 10

QLDClaudie River 12° 48’ 143° 18’ 20m 7 10

Chillie Beach 12° 38’ 143° 24’ 03m 3 10

3

PNGBensbach WP 05° 03’ 141° 17’ 25m 1 10

Bimadebum WP 03° 08’ 142° 03’ 40m 1 10

QLDClaudie River 12° 48’ 143° 18’ 20m 1 10

Chillie Beach 12° 38’ 143° 24’ 03m 1 10

A.

cras

sica

rpa

2

PNGBensbach WP 85° 03’ 141° 17’ 25m 2 10

SW of Boset WP 71° 07’ 141° 05’ 100m 3 10

QLD

Captain Billy road 11°41’ 142° 42’ 100m 2 10

Russel Gap & CK 11° 52’ 145° 19’ 60m2 *

3

PNGBensbach WP 85° 03’ 141° 17’ 25m 2 10

SW of Boset WP 71° 07’ 141° 05’ 100m 2 10

QLDCaptain Billy road 11°41’ 142° 42’ 100m 2 10

Russel Gap & CK 11° 52’ 145° 19’ 60m 2 *

A.

man

giu

m

Note * - Provenance Russel Gap & CK was excluded due insufficient sample size

ML 2 ML 3

With two leaders With more than two leaders

Two leaders Four leadersThree leaders

Figure 3: Wood specimens obtained from two ML classes.

STUDY LOCATION

• Established at the How Swee Estate, Kuala Lipis, Pahang (Lat: 40 20.5’N, Long: 1010 55.5’E ,Alt: 91.50 m asl.)

• Mean annual temperature: 270C.

• Annual rainfall: 2,211 mm.

• Soil description: Deep, brownish yellow - yellowish

brown fine sandy loam , weak to moderate medium - fine sub angular blocky structures.

FIELD TRIAL

Figure 4: Location of the Study Site in Kuala Lipis, Pahang where the specimens were taken

A trial of A trial of A. mangiumA. mangium

A trial of A trial of A. crassicarpaA. crassicarpa

• The samples tested according to BS373:1957-Testing of Small Clear Specimen of Timber for :

i) i) Physical - - specific gravity (SG), radial and tangential

shrinkages. ii) Mechanical - modulus of elasticity

(MOE) and modulus of rupture (MOR) properties. • Data - subjected to ANOVA of the

different sources using SAS version 6.12 software.

• Mean values - compared and separated by Duncan’s New Multiple Range Test.

Schematic diagram of sample used in this study.

Sample tested for static bending

RESULTS AND DISCUSSIONS

Table 2: Summary of physical and mechanical properties of A. crassicarpa and A. mangium

SpeciesSource of Variation

Physical Mechanical

Specific Gravity

Radial Shrinkage

Tangential Shrinkage

Static Bending MOE (N/mm2)

Static Bending MOR (N/mm2)

F Value F Value F Value F Value F Value

Acaciacrassicarpa

Multiple Leader

367.57* 732.63* 1002.47* 482.02* 630.2*

Provenance 0.73ns 0.15ns 0.41ns 1.73ns 1.12ns

Acacia mangium

Multiple Leader

0.11ns 0.83ns 0.83ns 0.54ns 0.15ns

Provenance 10.78* 7.16* 16.85* 16.43* 6.85*

* Significant at p<0.05.ns - not significant

- A. crassicarpa: significant differences between ML- A. mangium: significant differences between provenance

Figure 5: Mean Value of SG, Radial and Tangential Shrinkages, MOE and MOR between ML2 and ML3 of A. crassicarpa

Physical Mechanical

a

a

a

a

a

b

b

b

bb

ML2 ML3 ML2 ML3

• Significant differences of physical and mechanical properties between ML classes BUT not between provenances

• ML2 produced higher mean values in terms of specific gravity, MOE and MOR compared to ML3 because ML2 produced bigger diameter stem size – infering larger heartwood portion, higher amount of wood substance to cell cavity and thus higher specific gravity (SG)

• SG is closely related to wood mechanical properties (Zhang, 1997).

A. crassicarpa

• However, ML2 showed lower shrinkage (radial and tangential) than ML3 – thus growth stress is more pronounced in ML 3 compared to ML 2.

• ML 3 experience more stress as the result of more injuries during the singling operation compared to ML 2.

(assumption: When no. of leaders removed increased, injuries increased)

Figure 6: Specific Gravity, Radial and Tangential Shrinkages, MOE and MOR of different Provenances of A. mangium.

Mechanical0.45b 0.46a

0.44c

0

0.1

0.2

0.3

0.4

0.5

Sp

ec

ific

Gra

vit

y

Physical

A. mangium

• Significant differences of physical and mechanical properties between provenances classes BUT not between ML classes

• Provenance from Bensbach WP perform the best while SW of Boset WP - poorest in terms of physical and mechanical properties

• Different provenances/genotypes expressed different capabilities in terms of growth and physiological function including wood properties.

Table 3 : Physical properties of important plantation species

SPECIES SPECIFIC GRAVITY

RADIAL SHRINKAGE

(%)

TANGENTIAL SHRINKAGE

(%)

REFERENCES

Acacia crassicarpa 0.47 1.52 3.08 Abel (1997)

*A. crassicarpa (ML2) 0.45 1.40 3.59 Present study

*A. crassicarpa (ML3) 0.48 2.89 5.83 Present study

Acacia mangium 0.51 1.95 3.65 Hazani (1994)

*A. mangium (MLa) 0.45 3.07 3.69 Present study

*A. mangium (MLb) 0.46 3.69 4.43 Present study

*A. mangium (MLc) 0.44 2.71 3.25 Present study

Swietenia macrophylla 0.54 1.40 2.20 Haslett et. al. (1991)

Tectona grandis 0.70 0.70 1.10 Haslett et. al. (1991)

Gmelina arborea 0.49 1.20 2.30 Haslett et. al. (1991)

Hevea brasiliensis 0.65 NA NA Razali & Hamami (1992)

Note: MLa - Multiple leader (Captain Billy Road) ML2 - Multiple leader with 2 leadersMLb - Multiple leader (Bensbach WP) ML3 - Multiple leader with

> 2 leadersMLc - Multiple leader (SW of Boset WP)

Table 4 : Mechanical properties of important plantation species

SPECIES MOE

N/mm2

MOR

N/mm2

REFERENCES

Acacia crassicarpa 6499.43 66.69 Abel (1997)

*A. crassicarpa (ML2) 9858.4 89.63 Present study

*A. crassicarpa (ML3) 7557.7 60.4 Present study

Acacia mangium 9908 74.5 Wang (1989)

*A. mangium (MLa) 8676 72.2 Present study

*A. mangium (MLb) 10165 83.0 Present study

*A. mangium (MLc) 7197 52.4 Present study

Swietenia macrophylla 9483.36 91.77 Haslett et. al. (1991)

Tectona grandis 12134.62 120.33 Haslett et. al. (1991)

Gmelina arborea 8769.56 81.58 Haslett et. al. (1991)

Hevea brasiliensis 9240 66 Razali & Hamami (1992)

Note: MLa - Multiple leader (Captain Billy Road) ML2 - Multiple leader with 2 leadersMLb - Multiple leader (Bensbach WP) ML3 - Multiple leader with

> 2 leadersMLc - Multiple leader (SW of Boset WP)

CONCLUSION • Different species responded differently on

the physical & mechanical properties based on ML and provenances differences.

• Strength is associated with ML classes i.e. the lesser the number of stems, the better the physical and mechanical properties.

• Based on the MOE values obtained, it is assumed that such wood sources would have similar utilization to selected important plantation species such as Hevea.