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Implications for comparability of laboratory experiments revealed in studies on the effects of population density on the vigour in groups of Coptotermes lacteus (Froggatt) and Nasutitermes exitiosus(Hill) (Isoptera: Rhinotermitidae, Termitidae)
1983 - IRG/WP 1197
(Summary of paper 1194)
The vigour - survival and wood consumption - of groups of Coptotermes lacteus and Nasutitermes exitiosus was measured when termites were kept at different population densities (g termites/ mL) by changing group size and/or volume of the holding container. A characteristic pattern emerged. At low population densities (< 0,01 g/mL) performance of termites improved with an increase in group size; at higher population densities it tended to decline. The impact of altering group size and container volume on termite vigour was most pronounced at low densities; at higher population densities, performance tended to be more stable but declined markedly when termites became overcrowded. In most jar-type experiments on termites, especially those conducted in Europe and the U.S.A., small groups of termites are housed in disproportionately large jars, resulting in very low, sub-optimal population densities. Suggestions are made for improvements in experimental design that would lead to an enhancement of the comparability of results from different laboratories.
M Lenz, R A Barrett, E R Williams
Partial seasoning and preservative treatment systems for pine roundwood
1982 - IRG/WP 3187
Experimental trials at FRI, Rotorua showed that the steaming schedule normally used for steaming and venting is also suitable for steaming and vacuum seasoning. Applying vacuum of up to -84 kPa immediately after steaming did not increase the initial loss of wood moisture significantly in comparison to steam/venting. The main improvement to wood condition by using steam/vacuum appeared to be to dis...
A J Bergervoet
Shockwaves in wood preservation
2005 - IRG/WP 05-40308
Shockwaves are strong perturbations in aerodynamics that propagate at supersonic speeds independent of the wave amplitude. Physically the occurrence of shockwave is always characterized in a fluid flow by instantaneous changes in pressure, velocity and temperature. In this paper we describe a new wood preservative injection system that has been developed utilizing the non-linear pressure spike beh...
G Jagadeesh, R Lal, G Ravikumar, K S Rao
Social and economocal impact of an extension of service life resulting of an adequate preventive treatment. Application to wooden components used in urban areas with a high density of population
1993 - IRG/WP 93-50001-15
Le document évalue les problèmes rencontrés en zone urbaine pour le sauvetage des constructions: coordination de la lutte, délimination des chantieres et des périmètres d'investigation, nuisances causées par les interventions, risques pour la santé, risques pour l'environnement. Coûts. Comparaison socio-économique du traitement préventif et des interventions à posteri...
A T De Lelis, G A C Lopez
Detection of termite attack in wood using acoustic emission
1989 - IRG/WP 2331
Acoustic emission (AE) is the elastic wave produced by the strain energy released in the process of fracture of a material and propagates through it. The object of this report is to detect AEs produced by the termite activities and to evaluate the possibility of using an AE monitoring test to nondestructively detect the termite attack in wood. It was revealed that AEs were detected from the specim...
Y Fujii, M Noguchi, Y Imamura, M Tokoro
Survey of practical methods for conditioning of forest products before preservative treatment
1971 - IRG/WP 39
The seasoning of forest products is undertaken for a wide range of end uses and is becoming increasingly required for applications and building construction and secondary manufacturing industries. A wide range of applications of new technology and specifically required seasoning schedules is being actively developed for such requirements, but less attention has been given to the means by which woo...
J Rak, T S McKnight
Some Experiences with Stake Tests at BAM Test Fields and in the BAM Fungus Cellar
Part 1: Comparison of Results of Visual Assessments and Determinations of Static Moduli of Elasticity (MOE)
2005 - IRG/WP 05-20319
With examples of routine in-ground stake tests differences are shown in the performance of wood preservatives at the BAM test fields Lehre and Horstwalde and in the BAM fungus cellar. Signs of attack of micro-organisms were assessed visually according to EN 252. Periodical determinations of static moduli of elasticity (MOE) revealed the influence of the attack on the elastic properties of the wood...
M Grinda, S Göller
Wood preservation sites polluted by CCA. Is potassium diphosphate incubation a catalyst for the electrodialytic remediation of these soils?
1998 - IRG/WP 98-50106
As part of an evaluation of a newly developed electrodialytic soil remediation technique, we investigated the incubation of a contaminated soil (from a Portuguese wood preservation site polluted with CCA) with potassium diphosphate as a possible catalyst for the removal of heavy metals and metalloids. A chemical sequential extraction scheme (SE) applied to the soil has shown that the potassium dip...
A B Ribeiro, G Bech-Nielsen, A Villumsen, A Réfega, J Vieira e Silva
The results of detection on CCA components of the soils contacted with CCA-treated woods - A trial study for the availability of the burial Method as a disposal CCA treated wood waste
1993 - IRG/WP 93-50005
The objecteve of this experiment is to get a knowledge that, when CCA treated wood wastes were buried in a soil as a disposal, the soil would be or not be contaminated by the components of CCA preservatives in wood wastes. The specimens used were cutting logs and chips made of the CCA treated electric pole waste. The soil was buried to the 15 cm depth and the log specimens were set in the soil for...
K Suzuki, H Sonobe
Variation in field test performance of untreated and CCA-treated lesser-known Surinamese wood species
2000 - IRG/WP 00-20213
In Suriname three different field test sites have been used to verify the biological durability of CCA-treated wood and a range of wood species including lesser-known and lesser-used wood species. In total 37 tropical wood species were tested untreated and for 17 of the less durable species CCA-treatments were included as well. Although the three sites are located in the tropical region they diffe...
J Van Acker, M Stevens, L Comvalius
In vitro antifungal activity of chilli against wood degrading fungi
2006 - IRG/WP 06-10572
The efficacy of chilli juice and/or chilli extract oleoresin as antisapstain agents was evaluated against two common sapstain fungi, Sphaeropsis sapinea and Leptographium procerum. Possible synergy between chilli juice and Lactobacillus casei as antisapstain agents was also assessed.
Both the chilli juice and the oleoresin showed moderate antifungal activity. No growth of the test fungi was obse...
T Singh, C Chittenden, D Vesentini
Biological variability in the oxalate/oxalate decarboxylase system among five isolates of the wood-degrading fungus Meruliporia incrassate
2006 - IRG/WP 06-10573
The “dry-rot” wood decay fungus Meruliporia incrassata has recently attracted attention, primarily in the western coastal United States, as a particularly destructive pest of building material. Recently, the US Environmental Protection Agency (EPA) has accepted a voluntary withdrawal of the historically effective chromated-copper arsenate (CCA) as a preservative for wood used in residential se...
C Howell, J Jellison
Fun with Soil Block Jars: Teaching fungal wood decay in the classroom
2006 - IRG/WP 06-10574
In this world of increasing complexity and technological advancements, it is ever more important to raise scientifically literate children. The National Science Foundation Teaching Fellowship Program (NSF GK-12) at the University of Maine provides an opportunity for advanced graduate students in science, mathematics and engineering to bring their knowledge, as well as the latest equipment, to stud...
C Howell, L Gott, B Meehan
The effect of high and low boron soils on foraging termite behaviour and their metabolic systems
2007 - IRG/WP 07-10602
The highest concentrations of boron are found in ground water and soils of some of the driest climate areas (arid and semi arid regions) in the world. This present study examined the various concentrations of boron levels on filter papers against the subterranean termite species Coptotermes from different provenances and different boron soil levels. The termites were presented with no-choice bioas...
B M Ahmed, J R J French, P Vinden
On the changes of natural durability of wood sterilised by gamma radiation
2006 - IRG/WP 06-10571
The preliminary study data of natural durability of wood in lab conditions against rot fungi dependency on different sterilisation method have been presented. In the research, white rot fungus Schizophyllum commune Fr.: Fr. and brown rot fungus Poria placenta (Fries) Coke sensu J. Erikson. on the Scots pine were tested. Cobalt 60Co was used as a gamma radiation source at the dosage of 30 kGy. Cont...
R Despot, M Hasan, M Glavaš, G Rep
Correlation between modulus of elasticity, mass losses and FTIR spectra of copper treated decayed wood
2006 - IRG/WP 06-10580
The composition of copper-based preservatives will change from copper-chromium to copper-ethanolamine, due to environmental demands. The most important drawback of copper-impregnated wood is the presence of tolerant fungal organisms that have developed an ability to degrade such preserved wood. In order to elucidate these processes, specimens (0.5×1.0×15 cm) made of Norway spruce (Picea abies) w...
M Humar, B Bucar, F Pohleven
Laboratory Evaluation of Soft Rot Resistance of Non-Durable Lesser-Known Malaysian Hardwoods
2006 - IRG/WP 06-10582
Resistance of six non-durable lesser-known Malaysian hardwoods, Pulai (Alstonia spp.), Rubberwood (Hevea brasiliensis), Ludai (Sapium spp.), Jelutong (Dyera costulata), Gaham Badak (Blumeodendron tokbrai) and Kayu arang (Diospyros spp.) compared with temperate Scots pine sapwood (Pinus sylvestris), were evaluated using the unsterile soil burial (mixed with Chaetomium globosum) versus vermiculite-b...
A H H Wong
The role of oxalic acid in tolerance to N’N-naphthaloylhydroxylamine in Tyromyces palustris
2006 - IRG/WP 06-10584
Certain wood decay fungi exhibit tolerance to one or more wood preservatives. Copper tolerance of brown-rot fungi has been studied in our laboratory for the past six years. We have observed some degree of tolerance to N’N-naphthaloylhydroxamine (NHA), a recently patented termite bait, by the brown-rot fungus Tyromyces palustris TYP-6137. In an effort to try and confirm this tolerance in other is...
R A Arango, C A Clausen, F Green III
Isolation and characterization of hydroxyl-radical-producing glycopeptide genes from the white-rot basidiomycete Phanerochaete chrysosporium
2006 - IRG/WP 06-10588
During wood decay, the white-rot basidiomycete Phanerochaete chrysosporium secretes low-molecular-weight glycopeptides that catalyze a redox reaction between O2 and electron donors to produce hydroxyl radical. This reaction accounts for most of the hydroxyl radical produced in wood-degrading cultures of P. chrysosporium. In combination with phenol oxidases, hydroxyl radical is believed to play a r...
H Tanaka, G Yoshida, Y Baba, K Matsumura, S Itakura, A Enoki
Blue Staining of Coated Modified and Unmodified Wood
2006 - IRG/WP 06-10589
We investigated resistance of unmodified, DMDHEU modified and oil heat treated uncoated and coated Scots pine wood against blue stain fungi. Both EN 152-1 and the reverse exposure tests showed excellent resistance of DMDHEU and especially of oil heat treated wood against blue staining. It is not needed to add any additional protective coating layers to prevent modified wood from staining. However,...
M Petric, M Pavlic, M Humar, M Tomažic
The effect of chitosan on the growth and physiology of two wood inhabiting fungi
2006 - IRG/WP 06-10590
The effect of chitosan on the wood inhabiting fungi Sphaeropsis sapinea and Trichoderma harzianum was evaluated at cellular level. Increasing concentrations of chitosan caused an increase in the amount of peroxide in cultures of S. sapinea, which was accompanied by a simultaneous decrease in superoxide. The same effect was not observed in T. harzianum. The growth of both fungi was inhibited when h...
D Vesentini, T Singh
Quantification of methylene bis thiocyanate in wood and its effect on a sapstain fungus Ophiostoma floccosum
2006 - IRG/WP 06-10591
The mobility and concentrations of MBT at different depths of wood billets (200 mm long, 40 mm in diameter) were determined using NMR spectroscopy and ICP-ASE, and then correlated the effect of wood MBT concentrations on growth of O. floccosum in a bioassay using stereomicroscopy and confocal laser scanning microscopy (CLSM).
The 13C NMR spectra showed the presence or absence of MBT in wood but w...
T Singh
Direct analysis from wood of the blue stain fungi Aureobasidium pullulans and Hormonema dematioides by denaturing gradient gel electrophoresis
2006 - IRG/WP 06-10595
Aureobasidium pullulans and Hormonema dematioides are the two organisms used in the EN 152 laboratory method for determining the effectiveness of preservatives against blue stain in service. The literature concerning the disfigurement of surface coatings and exposed timber in-service states that A. pullulans is the dominant blue stain fungus, due to its frequent isolation from stained material. In...
M J Ray, D J Dickinson
Decay resistance of coconut and rubber woods. Alternative wood species from Ghana
2006 - IRG/WP 06-10596
With the expanding local and world wide demand for tropical timbers, there is increased interest in the suitability of lesser–used timber species as alternatives for the forest based industries in order to ensure sustainable forest management. In the forests of Ghana, there are quite a number of timber species that are lesser known and have not been adequately used due to the absence of informat...
S Amartey, M Humar, B Donkor, F Pohleven
Resistance of pine and spruce heartwood against decay - The effect of wood chemical composition and coating with water-borne wood oil product
2006 - IRG/WP 06-10597
Natural durability of wood has been widely studied, but the combination of the natural durability and different treatments has not been the focus of many studies. The durability of wooden products is mainly based on the water permeability and the resistance against organisms. In this study, the water absorption and decay resistance of sapwood and heartwood of Scots pine and Norway spruce were exam...
H Viitanen, S Metsä-Kortelainen, T Laakso