Yusuf Sudo Hadi

Effect of the lateral growth rate on wood properties in fast-growing hardwood species

We investigated the feasibility of using several fast-growing tropical or subtropical hardwood species for timber production by measuring key wood qualities in relationship to the high rates of lateral growth. The trees tested were sampled from even-aged plantations of Acacia mangium, A. auriculiformis, hybrid Acacia (A. mangium × A. auriculiformis), Eucalyptus grandis, E. globulus, and Paraserianthes falcataria (Solomon and Java origin) that had already reached commercial harvesting age. The released strain of the surface growth stress (RS), xylem density (XD), microfibril angle (MFA), and fiber length (FL) were measured at the outermost part of the xylem at breast height in each tree. Results were then compared to the lateral growth rate (radius/age) at breast height, which provides a relative indicator of the amount of tree growth per year. Our findings indicated that RS was constant, regardless of lateral growth rate in each species. Similar results were observed for XD, MFA, and FL, with a few exceptions, suggesting that high growth rates do not intrinsically affect the wood properties of fast-growing tropical or subtropical species that have reached harvesting age. However, special attention must be paid to patterns of xylem maturation when developing plantations of such species.

Termite-Susceptible Species of Wood for Inclusion as a Reference in Indonesian Standardized Laboratory Testing

Standardized laboratory testing of wood and wood-based products against subterranean termites in Indonesia (SNI 01.7207-2006) (SNI) has no requirement for the inclusion of a comparative reference species of wood (reference control). This is considered a weakness of the Indonesian standard. Consequently, a study was undertaken to identify a suitable Indonesian species of community wood that could be used as a reference control. Four candidate species of community woods: Acacia mangium, Hevea brasiliensis, Paraserianthes falcataria and Pinus merkusii were selected for testing their susceptibility to feeding by Coptotermes formosanus. Two testing methods (SNI and the Japanese standard method JIS K 1571-2004) were used to compare the susceptibility of each species of wood. Included in the study was Cryptomeria japonica, the reference control specified in the Japanese standard. The results of the study indicated that P. merkusii is a suitable reference species of wood for inclusion in laboratory tests against subterranean termites, conducted in accordance with the Indonesian standard (SNI 01.7207-2006).

Smoked Wood as an Alternative for Wood Protection against Termites

Mindi wood (Melia azedarach) and sugi wood (Cryptomeria japonica) were smoked for 15 days using mangium wood (Acacia mangium), and for comparison purposes, wood preserved with 5 percent borax, polystyrened wood, and untreated control wood were prepared. All of the wood specimens were tested for resistance to (1) subterranean termites (Coptotermes curvignathus Holmgren) in the laboratory, (2) dry wood termites (Cryptotermes cynocephalus Light) in the laboratory, and (3) subterranean termites in the field or via in-ground tests. The results showed that (1) mindi wood was more resistant than sugi wood to subterranean termite and dry wood termite attacks; (2) with regard to the Indonesian termite test standard, smoke treatment increased wood resistance to termite attacks, matching the highest resistance class of subterranean termites and dry wood termites; and (3) mindi wood offered equal resistance compared with polystyrened wood and wood preserved with borax, but in terms of the in-ground test, the smoke treatment did not affect wood resistance to termite attack, presumably because of leaching that occurred during the exposure test.

Physical-Mechanical Properties of Glued Laminated Timber Made from Tropical Small-Diameter Logs Grown in Indonesia

ABSTRACT The aim of this study was to determine the physical and mechanical properties of glued laminated timber (glulam) manufactured from small-diameter logs of three wood species, Acacia mangium (mangium), Maesopsis eminii (manii), and Falcataria moluccana (sengon), with densities of 533, 392, and 271 kg/m 3 , respectively. Glulam measuring 5 cm by 7 cm by 160 cm in thickness, width, and length, respectively, was made with three to five lamina, or layers, and isocyanate adhesive. The glulams contained either the same wood species for all layers or a combination of mangium face and back layers with a core layer of manii or sengon. Solid wood samples of the same size for all three species were included as a basis for comparison. Physical-mechanical properties and delamination tests of glulam referred to JAS 234:2003. The results showed that the properties of same species glulam did not differ from those of solid wood, with the exception of the shear strength of glu-lam being lower than that of solid wood. Wood species affected glulam properties, but three- and five-layer glulams were not different except for the modulus of elasticity. All glulams were resistant to delamination by immersion in both cold and boiling water. The glulams that successfully met the JAS standard were three- and five-layer mangium, five-layer manii, and five-layer mangium-manii glulams.Keywords : Glulam, solid wood, small-diameter logs, physical and mechanical roperties, delamination

Relationship between Released Strain and Growth Rate in 39 Year-Old Tectona grandis Planted in Indonesia

Summary In order to clarify the growth stress mechanism of tree species in tropical forest, peripheral and internal longitudinal released strains in 39 year-old teak (Tectona grandis) trees planted in West Java, Indonesia were investigated using the strain-gauge technique. Results showed that both of the peripheral and internal longitudinal released strains were not affected by the rate of growth of the trees. However, released strains distribution inside tree stem, from pith to periphery, were significantly affected by growth rate; slow growing trees generate steeper released strain gradients.

Resistance of Particleboards Made from Fast-Growing Wood Species to Subterranean Termite Attack.

Laboratory-made particleboards were tested for their resistance to subterranean termite, Coptotermes curvignathus Holmgren (Order Isoptera, Family Termitidae) by Indonesian standard SNI 01.7207–2006, during four weeks and at the end of the test their mass loss percentage and feeding rate were determined. Particleboards consisted of: jabon (Anthocephalus cadamba, Family Rubiacea) with a density of 0.41 g/cm3; sungkai (Peronema canescens, Family Verbenaceae) with a density of 0.46 g/cm3; mangium (Acacia mangium, Family Rhamnaceae) with a density of 0.60 g/cm3 separately and the three species mixture at a rate of 1:1:1. Densities of the boards were targetted at 0.60 g/cm3 and 0.80 g/cm3 by using 12% urea formaldehyde as binder with 2% paraffin as additive based on oven dry wood particle weight. The hand-formed mats and hot-pressing at 130 °C and 2.45 MPa for 10 min were applied. The results showed that particleboards density did not affect mass loss and feeding rate, but the particleboards made from higher density wood resulted in higher resistance to subterranean termite attack. The most resistant particleboards were made of magium, followed by sungkai, mixed species, and jabon.

Resistance of Smoked Glued Laminated Lumber to Subterranean Termite Attack

Abstract Timber from plantation forest mostly contains sapwood, and the heartwood part has a lot of juvenile wood, which has low resistance to attack by subterranean termites (Coptotermes curvignathus). Wood smoke created through pyrolysis contains numerous polycyclic aromatic hydrocarbons that could prevent termite attack. Three-layer glued laminated lumber (glulam) was created using either the same wood species (mangium [Acacia mangium], manii [Maesopsis eminii], or sengon [Falcataria moluccana]) for all layers or a combination of mangium as the face and back layers and a core layer of manii or sengon. Glulam samples were exposed to smoke from mangium wood for 15 days, preserved with imidacloprid, or left untreated. All glulams were tested against subterranean termites according to the Indonesian standard. Gas chromatography revealed that smoke from mangium predominantly contained acetic acid, cyclobutanol, and phenolic compounds. Smoked glulam was more resistant to subterranean termite attack than untr...

Feeding rate of termites in wood treated with borax, acetylation, polystyrene, and smoke

Mindi (Melia azedarach) wood with density of 0.43 g/cm3 from Indonesia and sugi (Cryptomeria japonica) wood with density of 0.34 g/cm3 from Japan were treated with borax preservative, acetylation, polystyrene, and smoke. Treated and untreated wood samples were tested for resistance against subterranean termite (Coptotermes curvignathus) and dry wood termite (Cryptotermes cynocephalus) in the laboratory according to Indonesian standards. In addition to determining resistance of treated woods to termite attack, this work also evaluated termite feeding rates. The results showed that mindi has better resistance to subterranean and dry wood termite attack than sugi. All treatments effectively increased resistance to subterranean and dry wood termite attacks as shown by treated wood samples having less weight loss, higher resistance class, higher termite mortality, and a lower termite feeding rate compared to untreated wood. Daily termite feeding rate of untreated mindi was 50.3 μg/termite and sugi 95.8 μg/termite, the feeding rate of sugi was higher than mindi probably because sugi has a lower density and contains early wood, which both make termite feeding activity easier. The wood treatments effectively decreased the daily feeding rate of the termites.

Composite Flooring Quality of Combined Wood Species Using Adhesive from Merbau Wood Extract

Abstract Polyphenol chemical components extracted from merbau (Intsia spp.) wood exhibit a strong affinity for resorcinol and formaldehyde in alkaline conditions, forming a copolymer that could ser...

Effect of Urea Concentration and Vacuum Treatment on Physical and Mechanical Properties of Methyl Metacrylate Bamboo

Betung bamboo (Dendrocalamus asper) samples were obtained from Bogor area, Indonesia. The samples were air dried, and then immersed into methyl metacrylate-urea solution for 24 hours prior to irradiation. Urea was added into methyl metacrylate (MMA) with concentration of 1%, 3%, and 5%, and without urea as control. The samples were vacuumed at 35 mmHg for five minutes prior to immersion, and without vacuum were done as well as control. The samples were wrapped up with aluminum foil and then with polyvinyl sheet, and irradiated with 60Co gamma ray with 40 kGy. After opening the wraps, the samples were dried in the oven at 70°C for 24 hours. For comparison, the samples of control or original bamboo were also prepared. The all samples were tested for physical and mechanical properties. Factorial randomized complete design 2 × 4 was used for analytical purpose the factors were vacuum treatment and urea concentration. The results showed that polymer loading of MMA-bamboo reached 10.7–12.8%, and the physical and mechanical properties were better than the origin. Vacuum treatment enhanced hardness only, and urea enhanced polymer loading and physical properties but reduced mechanical properties, and the addition of urea at 1% could be satisfied.