Wood Quality of Plantation Grown Azadlrachta Excelsa (Jack) Jacobs from Malaysia

Sing Boupha, Lathsami Boupha (1998) Wood Quality of Plantation Grown Azadlrachta Excelsa (Jack) Jacobs from Malaysia. PhD thesis, Universiti Pertanian Malaysia.

[img] PDF
1137Kb

Abstract

Azadirachta exceIsa is a fast growing tree, with tall and straight clear bole. Six planted A. excelsa trees of three growth rates (dominant, co-dominant and suppressed) under the same site conditions and the same age were sampled at three height levels and three radial positions to provide specimens to investigate among growth-rates and within tree variations of anatomical, physical and mechanical properties. Mean vessel, ray and fibre contents were 18.99%, 19.08% and 62.74% respectively. Mean fibre length was 1.12 mm, fibre diameter 24.17µm, fibre lumen diameter l1.55µm, and fibre wall thickness 6.31µm. Mean specific gravity (SG) was 0.59, green moisture content 96.30%, tangential shrinkage 5.64%, radial shrinkage 2.61 % and volumetric shrinkage of 9.3%. Mean shear parallel to the grain was 13.34 MPa, compression parallel to the grain 41.95 MPa, modulus of elasticity (MOE) 6862 MPa, modulus of rupture (MOR) 83.85 MPa and hardness 3.03 kN. The anatomical, physical and mechanical properties of A. excelsa evaluated in this study were comparable to many of the light hardwood species. Therefore, the tree is suitable for a wide range of utilisation. Between growth-rate variations of all properties analysed showed significant difference. In general, dominant trees have thicker fibre wall, higher specific gravity and strength properties than the co-dominant and suppressed trees. The considerable variations in specific gravity, in strength and in anatomical parameters among" trees, if genetically controlled, offers possibilities for selection of breeding stock from seed or cuttings with desirable wood quality. Within tree variations was more pronounced in radial than in vertical direction, suggesting that diameter growth is an important factor contributing to the variations than the height growth. Samples from the midpoint between the pith and the bark were found to have highest specific gravity and also more dimensionally stable in dimension compared to the outer and inner part.

Item Type:Thesis (PhD)
Subject:Azadirachta - Malaysia
Subject:Wood - Research - Malaysia
Chairman Supervisor:Associate Professor Mohd Hamami Sahri, PhD
Call Number:FH 1998 11
Faculty or Institute:Faculty of Forestry
ID Code:9966
Deposited By: Mohd Nezeri Mohamad
Deposited On:28 Feb 2011 03:58
Last Modified:29 Oct 2012 09:13

Repository Staff Only: item control page

Document Download Statistics

This item has been downloaded for since 28 Feb 2011 03:58.

View statistics for "Wood Quality of Plantation Grown Azadlrachta Excelsa (Jack) Jacobs from Malaysia"


Universiti Putra Malaysia Institutional Repository

Universiti Putra Malaysia Institutional Repository is an on-line digital archive that serves as a central collection and storage of scientific information and research at the Universiti Putra Malaysia.

Currently, the collections deposited in the IR consists of Master and PhD theses, Master and PhD Project Report, Journal Articles, Journal Bulletins, Conference Papers, UPM News, Newspaper Cuttings, Patents and Inaugural Lectures.

As the policy of the university does not permit users to view thesis in full text, access is only given to the first 24 pages only.