Abstract:
Bio deteriorating agents' damage on forest products in the area o f
construction, furniture, and standing trees is a big problem in Ethiopia. This
is one o f the major causes in the country that led inappropriate utilization
and destruction of forests and endangering o f certain valuable timber species
such as Junipenisprocera, Hagenici abyssinica, Cordia afrcana, Podocarpus
falcatus and Pouteria adolfi-friederici where the first four have been
proclaimed not to be harvested from both federal and regional forests o f the
country (TGE, 1994) and the last one has been proclaimed by the Oromiya
Regional State (Oromiya Regional State, 2003).
The major sources o f construction material, forest industries, and woodbased
energy sectors are the natural forests while plantations contribute
about 10% (PTA, 1990). In Ethiopia, there are more than 320 timber species
that can supply saw log/lumber, but indeed have not been properly utilized.
In 2010,the gap between total demand (about 85 million m3) and supply
(about 11.5 million m3) o f industrial, construction and fuel wood was about
73 million m3 (EFAP, 1994), where demand exceeding the supply by more
than 730%. This has Jed to excessive and illegal cutting of trees and utilizing
o f more agricultural residues to meet the high deficit has been faced, which
in turn has a negative impact on soils and agricultural crops.
J procera has been considered as one o f the most versatile, prominent
structural/ construction, furniture, invaluable industrial and aesthetic
material in the country, which has been used without adequate knowledge o f
its durability and other properties. J. procera is among the few highly
exploited, improperly utilized, and endangered species while Eucalyptus E.
deglupta is an introduced and fast-growing species for promotion and
sustainable utilization. E. deglupta is not yet known by the development
sectors, manufactures, and end users in the country. Besides, wood
properties and silvicltural research results were not yet adequately
disseminated and popularized.
Wood quality requirements for sawn dried (seasoned) and dressed end
products can be grouped into five main categories: mechanical properties
(bending, stiffness, tensile, compression strength, hardness), dimensional
stability (low distortion, shrinkage, and collapse), biological performance
(consistent color, durability), and manufacturing performance (good
gluability, machining), and log processing performance (low splits, low
distortion) (Armstrong, 2003).
