Your search resulted in 146 documents. Displaying 25 entries per page.
Assessment of untreated Papua New Guinean timbers against subterranean termites. Progress Report 1
1990 - IRG/WP 1436
Eight major commercial timber species (Intsia palembanica, Pometia pinnata, Homalium foetidum, Dracontomelon dao, Calophyllum spp., Eucalyptus deglupta, Nothofagus spp., and Alstonia scholaris) were exposed in ground contact against termites. Five replicates of heartwood stakes of 25x25x250 mm³ of each species were randomly embedded in the soil. Results after 24 months exposure showed that Kwila ...
M Rokova, H C Konabe
Susceptibility of heartwood of three Pinus species to attack by the subterranean termite Coptotermes acinaciformis (Froggatt)
1994 - IRG/WP 94-20026
Heartwood of plantation-grown Pinus elliottii (slash pine), Pinus caribaea (Caribbean pine) and Pinus radiata (radiata pine) was obtained from a range of locations throughout Australia and New Zealand for use in a field bioassey with subterranean termites. Timber stock was analysed for a number of stilbene and flavonoid heartwood extractive components which could contribute to variation in suscept...
M J Kennedy, L L Dixon, B C Peters
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
The natural durability of wood in different use classes - PART II
2006 - IRG/WP 06-10598
The natural durability of important European wood species has been tested on 3970 speci¬mens in field trials. The wood was exposed at five test sites in Germany with different climates, at each site in European use class 4 and 3 (with and without soil contact). Within European use class 3 three different expositions were tested: vertical with sheltered end grain, vertical unsheltered and horizont...
A O Rapp, U Augusta, K Brandt
Tree crown architecture: a tool for decay resistance evaluation
2013 - IRG/WP 13-10793
The variability of natural durability contributes to the bad perception of some wood end-users. In our search, we need to adjust our methods and strategies to estimate natural durability and extract higher value from wood resources. Architectural analysis is essentially a detailed, multilevel, comprehensive and dynamic approach to plant development. Numerous biological process which impact some wo...
N Amusant, J-B Anouhé Say, A Amissa, J Beauchène, F Niamké, E Nicolinni
On the reasons of Prunus africana natural durability
2007 - IRG/WP 07-10611
Analysis of Prunus africana heartwood extractives was studied with the aim of understanding the reasons for its high natural durability. Soxhlet extractions of wood powder using different solvents were carried out. Effect of each extracts at different concentrations was evaluated on the growth of several fungi among which Coriolus versicolor, Poria placenta, and Aureobasidium pullulans. Results sh...
F Mburu, S Dumarçay, M F Thévenon, P Gérardin
Methods for Determining the Role of Extractives in the Natural Durability of Western Redcedar Heartwood
2007 - IRG/WP 07-20356
The durability of western redcedar heartwood is influenced by a number of different extractives operating by different mechanisms. In order to guide a systematic isolation of extractives with high fungal toxicity, a micro-bioassay has been developed for measuring the fungal toxicity of extractive fractions. Two additional assays quantify the anti-radical and metal chelating properties of cedar ext...
R Stirling, C R Daniels, J E Clark, P I Morris
Potentiality of use extracts from Tetraclinis articulata like biocide against wood destroying organisms: Reticulitermes santonensis
2007 - IRG/WP 07-30418
Screening trials were conducted to determine the antitermitic and antifungal properties of essential oil and methanolic extractives obtained from Tetraclinis articulata heartwood. Extract-treated cellulose pads were used to evaluate antitermitic activity and complete termite mortality was obtained with the essential oil: the threshold is situated under 5% (v/v). Standardised tests according Europe...
F El hanbali, N Amusant, F Mellouki, M Akssira, C Baudasse
Influence of Grain Direction on Penetration, Retention, and Leaching of CCA(C) in Sapwood and Heartwood of Kenyan-Grown Eucalyptus saligna and Acacia mearnsii
2007 - IRG/WP 07-40383
Penetration, retention, and leaching of CCA (C) in relation to grain orientation were tested in small (50mm x 50mm x 200mm) sapwood and heartwood samples of Eucalyptus saligna and Acacia mearnsii. In both sapwood and heartwood of the two species, the results showed a consistent pattern: Transverse > Radial > Tangential. Whereas penetration, retention, and leaching were significantly high i...
R Venkatasamy
Influence of Grain Direction on Penetration, Retention, and Leaching of CCA(C) in Sapwood and Heartwood of Kenyan-Grown Cupressus lusitanica and Pinus patula
2007 - IRG/WP 07-40384
The influence of grain orientation on penetration, retention, and leaching of CCA (C) was tested on small samples of sapwood and heartwood of Cupressus lusitanica and Pinus patula. Samples measuring 50mm x 50mm, and 200mm in the longitudinal axis were sealed to expose only transverse, or radial, or tangential faces, pressure treated with 6% CCA (C), and penetration, retention and leaching of the ...
R Venkatasamy
The effect of wood moisture content and rod dosage on movement of boron through Douglas-fir heartwood
2007 - IRG/WP 07-30431
The potential for moisture sorption by boron rods following application to wood to affect subsequent boron diffusion was investigated in small Douglas-fir blocks conditioned to 30, 60 or 90% moisture content (MC). MCs tended to decline over the 180 day test period, but there was no evidence that the rods acted to draw moisture away from the wood. As expected, boron movement tended to increase with...
Y Cabrera, J J Morrell
Treatment of Selected Lesser Used Timber Species against Subterranean Termites using Heartwood Extracts from Teak (Tectona grandis) and Dahoma (Piptadeniastrum africanum)
2007 - IRG/WP 07-30434
Lesser used timber species represent a valuable material for all-purpose uses but the problem is that most of them are not durable. They have, for this reason, been treated with all manner of chemicals to enhance their natural durability, especially in the tropics. Often, most of these chemicals pose a threat to the environment. Currently, one probable measure of avoiding such a threat to the envi...
A Asamoah, C Antwi-Boasiako
Comparative Laboratory Leaching Test Methods to Study Post-Treatment Storage Period Impacts on CCA Leachability and Fixation in Treated Kempas (Koompassia malaccensis) Heartwood
2007 - IRG/WP 07-20376
Three laboratory leaching test methods were compared to determine the effects of different post-treatment storage fixation periods on leachability/fixation of CCA components from treated kempas (Koompassia malaccensis) permeable heartwood. End-sealed test wood blocks of permeable were treated with CCA to target retention of 5.6 kg/m3, immediately stored to fix at ambient conditions for 0 and 48 ho...
A H H Wong, H C Lai
Influence of ring width and wood density on durability of oak heartwood
2008 - IRG/WP 08-10639
Oak (Quercus sp.) is considered as one of the most durable European wood species. The most important factor influencing oak durability was extractive content. In our work, we were interested in if oak-wood durability is affected by ring-width and related density. Therefore, oak heartwood specimens made of boards with different ring widths were exposed to five different fungal species Daedelea quer...
M Humar, P Oven, F Pohleven
A hypothesis on a second non-biocidal property of wood extractives, in addition to toxicity, that affects termite behavior and mortality
2008 - IRG/WP 08-10638
While it is has long been recognized that heartwood extractives affect termite behavior, the exact cause and relationship between total extractives, extractive types, and termite resistance remains unclear. Generally, researchers have proposed that the extractives are toxic and/or repel termites. We propose, based on the well known fact that many extractives have excellent antioxidant properties...
T P Schultz, K Ragon, D D Nicholas
Evaluation of natural durability of solid wood and mixed heartwood-sapwood Cypress (Cupressus sempervirens L.) plywood against Basidiomycete fungi
2008 - IRG/WP 08-10645
The aim of this research was to study the response of mixed plywoods composed of durable heartwood and non-durable sapwood to fungal attack. For this purpose, the species of Cupressus sempervirens (cypress) was chosen for its well-known durable heartwood. The evaluation of durability of plywood panels against fungi was done according to ENV 12038 and the fungi used were Coriolus versicolor (CV) an...
F Faraji, M F Thévenon, N Lemenager, B Thibaut
Validity of above ground testing according to ENV 12037
2008 - IRG/WP 08-20379
The standard ENV 12037 for testing of treated and untreated wood (lap-joint) exposed above ground
was issued in 1996 by The European Committee for Standardization. A draft for the development of the standard was presented by CEN-TC 38/WG 25/DOC N 076 in 2002. For a test to become valid the median rating of decay for untreated control replicates (Scots pine sapwood) must be equal or greater than ...
Ö Bergman, U Råberg, N Terziev
Spruce and pine heartwood treatment by means of microwave radiation
2008 - IRG/WP 08-40411
An easier penetrability and a more even uptake of wood protection agents is aimed for the two most common wood species in Europe, namely Norway spruce (Picea abies) and Scots pine heartwood (Pinus sylvestris), particularly when there is a great difference in absorption behavior of sapwood and heartwood. Microwave conditioning can improve permeability, reduce density and heat conductivity and chang...
A Treu, H Rieche, H Militz
Spruce and pine heartwood treatment by means of microwave radiation
2008 - IRG/WP 08-40411
An easier penetrability and a more even uptake of wood protection agents is aimed for the two most common wood species in Europe, namely Norway spruce (Picea abies) and Scots pine heartwood (Pinus sylvestris), particularly when there is a great difference in absorption behavior of sapwood and heartwood. Microwave conditioning can improve permeability, reduce density and heat conductivity and chang...
A Treu, H Rieche, H Militz
Treatment of Selected Lesser Used Timber Species against Subterranean Termites using Heartwood Extracts from Teak (Tectona grandis) and Dahoma (Piptadeniastrum africanum)
2008 - IRG/WP 08-30476
Lesser used timber species represent a valuable material for all-purpose uses. However, most of them are not durable. They are, for effective utilization, often treated with all manner of toxic synthetic substances to enhance their natural durability, especially in the tropics where conditions favour their deterioration. Most of these toxic synthetic substances often pose a threat to the environme...
A Asamoah, C Antwi-Boasiako, K Frimpong-Mensah
Effects of planning and sanding on penetration and retention properties of some softwood species treated with copper azole
2008 - IRG/WP 08-40410
This work investigates the effect of some woodworking treatments on penetration and retention properties of four different (scotch pine—SP, Siberian scotch pine—SSP, Siberian larch—SL, and oriental spruce—OS) heartwood species with the waterborne preservative copper azole (CBA-A). A 2.4% active ingredient solution of CBA-A was applied for use in vacuum/pressure treatment of the heartwood s...
Ü C Yildiz, S Yildiz
Natural Durability of Some Heartwood from European and Tropical African Trees against Marine Organisms
2009 - IRG/WP 09-10682
This study aims to investigate the natural marine durability of some tropical and domestic wood species in marine environment. A total of 33 tree species, comprising 18 European and 15 tropical originated trees were exposed to marine conditions in 6 meters depth for a period of 14 months at east and west Black sea, Mediterranean, Aegean, and Marmara coasts. The results indicated that wood species...
S Sen, H Sivrikaya, M Yalçın
Termite resistance of pure and mixed heartwood-sapwood Cypress (Cupressus sempervirens L.) plywoods
2009 - IRG/WP 09-10693
The main objective of this research was to evaluate the ability of different plywoods made of durable heartwood and/or non-durable sapwood to resist termite damage. The well-known durable cypress (Cupressus sempervirens) was chosen for this study. The natural durability of cypress solid wood, divided into sapwood and heartwood, as well as the durability of 17 different laboratory manufactured plyw...
F Faraji, M-F Thévenon, B Thibaut
Durability and fungal colonisation patterns in wood samples after six years in soil contact evaluated with qPCR, microscopy, TGA, chitin- and ergosterol assays
2009 - IRG/WP 09-20402
There is a need to establish new objective and sensitive methods for early detection and quantification of decay fungi in wood materials. Molecular methods have proven to be a useful tool within wood protection issues, however, this field is still poorly explored and so far relatively few have used these methods within the field of wood deterioration. Among the techniques used in the indirect quan...
A Pilgård, G Alfredsen, I Børja, C Björdal
Effect of extractives on durability of Prosopis juliflora heartwood
2009 - IRG/WP 09-30518
The heartwood of Prosopis juliflora is resistant to fungal attack caused by different brown and white rot fungi. This durability due to the presence of high amounts of extractives decreases after extraction of these latter ones with different solvents. Heartwood extractives were effective in inhibiting the growth of the fungi. Depending on the concentration used, development of the fungal mycelium...
P Sirmah, K Iaych, B Poaty, S Dumarçay, P Gérardin