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Wood Preservation India; Current Scenario
2013 - IRG/WP 13-40630
This short note describes the present status of wood preservation research and its industrial application. Although good performing formulations have been developed by Indian research laboratories, industry has not tried to derive benefits from this development. Many unknown products are flooding the market for brush on applications with little benefit as the products have not been standardized.
Evaluation of Barrier Wrap Systems after 71 Months of Exposure
2013 - IRG/WP 13-40631
A 71 month study of the performance of booted samples in ground contact was conducted in AWPA hazard zone 4. Data indicated that excellent performance of wrapped systems, even over untreated wood, could be obtained. Instances of decay colonization or termite attack could all be attributed to some breaking of the integrity of the barrier system. Good performance for treatment below ground contact threshold was demonstrated.
H M Barnes, M G Sanders, G B Lindsey, C McIntyre
Annual Report 2012
2013 - IRG/WP 13-60341
Agenda 2013 Plenary Meeting
2013 - IRG/WP 13-60342
The 44th Annual Meeting of IRG Programme
2013 - IRG/WP 13-60344
The 44th Annual Meeting of IRG, Abstracts of Documents
2013 - IRG/WP 13-60343
IRG Documents 2013
2013 - IRG/WP 13-60358
Budget for 2013 (forecast June 3103)
2013 - IRG/WP 13-60345
Budget for 2014
2013 - IRG/WP 13-60346
Reporting minutes of the Plenary Meeting 2013
2013 - IRG/WP 13-60355
IRGWP Strategy development 2012-2013
2013 - IRG/WP 13-60356
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 wood properties like durability are linked with tree development. A better understanding of the inter-relationship between tree physiology through tree achitecture analysis and natural durability could be an approach to predict this property. This study explore the relation between the crown architecture, decay resistance and wood extractives in Dicorynia guianensis in order to propose tree crown architecture as an evalution decay resistance tool.
N Amusant, J-B Anouhé Say, A Amissa, J Beauchène, F Niamké, E Nicolinni
Activities of moulds on wood as a function of relative humidity during desorption and absorption processes
2013 - IRG/WP 13-10794
Three different types of indoor moulds: Penicillium brevicompactum, primary colonizer; Alternaria tenuissima, secondary colonizer and Trichoderma harzianum, tertiary colonizer, grown on wood were measured for their activities under different relative humidity levels. The activities were measured by isothermal calorimetry. The activities of the moulds changed with the change of the relative humidity levels. The optimal relative humidity levels are different for these three moulds. The mould activities were also different from desorption to adsorption processes under the same relative humidity levels. This might be caused by the moisture hysteresis properties of wood. Therefore, besides of relative humidity, water availability also plays an important role for mould growth. Such information should be taken into account for modelling mould behaviour on building materials.
Yujing Li, L Wadsö
Influence of a pulsed electric field on the growth of surface fungi
2013 - IRG/WP 13-10795
The colonization of mold and staining fungi are not only an aesthetical problem. Blue stain fungi are able to penetrate paint films. Maintenance of coatings on wood are time consuming and costly. A new approach uses a pulsed electric field (PLEOT) in order to protect wood against surface fungi. This technology is evaluated in non-sterile laboratory conditions on different coated and uncoated Scots pine sapwood and spruce wood samples exposed to a fungi mix for 12 weeks and in sterile test conditions on wood samples exposed to Aureobasidium pullulans and Ulocladium atrum for 8 weeks. The installation of PLEOT could reduce the growth of surface fungi. The addition of graphite to the coating led to significantly reduced growth of fungi on the front side of the samples using a fungi mix. The addition of graphite did not influence the growth of surface fungi. Growth of A. pullulans on the front side of wood samples in a sterile test showed to be slightly influenced by PLEOT, while growth inhibition of U. atrum was more pronounced on the back side of the wood samples.
M Starck, A Treu
Detection of Aureobasidium as the dominant fungus on coated wood
2013 - IRG/WP 13-10796
Wood is often covered with a coating in order to protect the surface. Unwanted dark mold growth on paint covered surfaces in external conditions is a familiar phenomenon. Simple microbial techniques have commonly been used to determine the dominant fungal species present in the discoloured area, for example morphological analysis of microscopic preparations of fungal pieces sticking to an adhesive tape. When using this method Aureobasidium is frequently recognized to be the dominant fungus. This is a curious outcome since this fungus can not be identified by its commonly occurring dark chlamydospores but only by the synchronous conidia production from young expanding hyphae. To understand the uncertainties in the diagnostics of the dominant molds on coated wood a case study is done on wood impregnated with raw linseed oil. The reason for selecting this oil treated wood is that raw linseed oil or its fatty acids are a common ingredient of coatings and a quick dense mold growth is assured. Three microbial techniques were used to detect Aureobasidium as the dominant species. The CFU technique based on colony forming unit counts of swap samples indicated a dominancy of more than 50% of Aureobasidium on wood impregnated with linseed oil. Adhesive tape preparation and examination of the culturable fungal microbiota, did not counter this degree of dominancy. The ability of Aureobasidium to grow on pure linseed oil provided supporting evidence of the dominancy of Aureobasidium.
E J Van Nieuwenhuijzen, M F Sailer, R A Samson, O C G Adan
Surface moulds and staining fungi on acetylated wood – effect of increasing acetyl content
2013 - IRG/WP 13-10797
Wood used in outside applications is susceptible to weathering and photo degradation, which often leads to surface discoloration, loss of brightness and surface deterioration. Research has shown that acetylated wood is more resistant against brown rot, white rot and soft rot, and more dimensionally stable than untreated wood. However, acetylated wood seems still to be disfigured by surface moulds and staining fungi. Samples of acetylated Southern Yellow pine at three different treatment levels; low, intermediate and high acetyl content were exposed outdoors at Ås (Norway) for a period of 9 months. Corresponding samples from the same material where tested according to a modified version of EN 15457 (agar plate test) using A.pullulans as test fungi. In the outdoor test unmodified wood had higher mould ratings than acetylated wood, and there was a tendency that samples with low acetyl content had lower mould ratings than samples with higher acetyl content. In the laboratory test, non-leached samples with high acetyl content had significantly higher mould rating than samples with lower acetyl content and unmodified samples. In this study a concentration of free acetic acid of 0.77% seemed to restrict growth of A.pullulans on samples of a high treatment level.
L Ross Gobakken, S Bardage, C J Long II
Preliminary evaluation of degradation patterns in wood samples from the Yenikapı shipwrecks
2013 - IRG/WP 13-10798
The uncovering of several shipwrecks during the excavation of the Marmaray Rail Tube Tunnel Project in Istanbul provides an important opportunity to evaluate waterlogged woods buried for centuries. Identification of these woods showed that a variety of species was used in the ships. One shipwreck (a galley) from the Yenikapı Marmaray was examined using electron microscopy. The micrographs revealed a wide range in the degree of deterioration in the samples. The results confirmed earlier observations that erosion bacteria and soft rot were the main degraders of waterlogged softwoods and hardwoods.
C Köse, A M Taylor
Communities of mold fungi on flooded building materials
2013 - IRG/WP 13-10799
A small building built to residential code was flooded using farmland pond water to a depth of two feet at Tuskegee University. The building was drained and left enclosed for an additional three weeks. A total of 168 material samples were removed either immediately after opening (wet) or seven months after flooding (dry). Wall materials sampled included fiberglass batt insulation, gypsum wallboard, wood stud, plywood panels, vinyl siding, and house wrap and were analyzed by cloning and sequencing to identify the mold species present both above and below the water line. The vinyl siding and house wrap had the lowest mold growth while the batt insulation had very high quantities of mold, followed by the paper siding of the gypsum. The common types of molds present included Aspergillus, Chaetomium, Fusarium, Trichoderma, and Stachybotrys. The different molds were analyzed for presence on the different types and components of wall materials in areas exposed above and below the water line. In addition, real-time PCR quantitated selected mold species on different building materials. The mold species found in the highest concentration were Aspergillus fumigatus, Paecilomyces variotii, Chaetomium globosum, and Stachybotrys chartarum. The batt insulation supported the highest concentration of mold after flooding, followed by the wood stud, plywood sheathing, and gypsum wallboard. The highest level of mold on the dry materials was Aspergillus fumigatus on the dry wood stud and Stachybotrys chartarum on the dry gypsum. The focus of the research was to show that flood waters can penetrate into wall cavities of a home and the different wall materials become a substrate for different molds to develop, which potentially cause problems for some susceptible individuals.
F Skrobot III, H Aglan, S V Diehl
High-throughput sequencing highlighted contrasted pioneer fungal communities associated to coniferous and deciduous wood preservation assays
2013 - IRG/WP 13-10800
Studying the fungal communities in the wood, in particular during the first events of the colonization, and the factors that underlie the dynamics of fungal species assemblages remain a challenge in ecology, because of the absence of fructification during the pioneer steps of wood degradation. The use of Next-generation DNA sequencing methods, which produce massive volumes of data, provided new perspectives in fungal molecular ecology. In this paper we used high throughput sequencing to identify factors influencing fungal colonisation during the early stages of wood decay. For this purpose wood pickets, from different wood species, were buried in an experimental site, located on the island of Oléron, and removed after six and nine months of incubation. Then, total DNA was extracted and a library of the fungal internal transcribed spacer (ITS-1) region was prepared for 454 pyrosequencing. Our results revealed a strong host effect on the fungal communities associated to different wood species together with a spatial effect on fungal diversity. The source of inoculum was also investigated with the same approach from soil samples, and results demonstrated that the major source of fungal inoculum was not located, or very weakly represented, in the close environment of our pickets. Finally, the application of high throughput sequencing approaches was investigated to improve standards in order to be more representative of natural conditions.
Y Mathieu, A Dassé, I Le Bayon, M Kutnik, L Harvengt, E Gelhaye, M Buée
An assessment of soft rot in preservative-treated poles in two test sites and two network areas in New South Wales
2013 - IRG/WP 13-10801
This document presents an extended summary of recent investigations into soft rot attack of preservative treated power poles from the re-inspection of samples selected from two field sites and two in-service trials located in New South Wales, Australia. The in-ground sapwood of selected poles was assessed by probing and, after core sampling, by microscopy to determine the severity and extent of soft rot attack. Data obtained during these assessments were compared with data from similar inspections that occurred approximately 10-15 years previously. The findings are discussed in relation to the influence of wood species, preservative type, location, inspection and remedial treatment practices on the rate of soft rot degrade. Additional comments are made regarding the effectiveness of conventional methodologies for assessing soft rot.
W D Gardner, M A Powell, C Kirton
Survival of Bursaphelenchus xylophilus exposed to different active ingredients of wood protectors
2013 - IRG/WP 13-10802
The pine wilt nematode (PWN) Bursaphelenchus xylophilus (Steiner and Buhrer 1934) Nickle, 1970 is a quarantine organism with a high potential to damage Conifer forests in Europe. This has driven the European Union to protect forest stands from the propagation and dispersion of this pathogen.The nematode was first detected in Europe in Setubal (Portugal) in 1999 and eradication measures were taken. However, these measures were unsuccessful in decreasing the infection level, leading to the announcement of new European regulations (2006/133/CE, Commission on 13 February 2006). The new regulations have not prevented the dispersion of this organism, as Bursaphelenchus xylophilus has been detected in wood material through commercial trade. Timber is a material with a free market in Europe, and although it is treated with specific products against wood decay organisms, the industrial sector is concerned whether the adopted thermal treatment measures used to treat wood (ISPM 15), is enough and if the wood treatments are effective against the nematode. For this reason, the aim of this work has been to continue with the evaluation of the effectiveness of more successful and commercial active ingredients in the formulations of wood preservatives currently used for the temporary and permanently protection of timber, in order to see if these products have a biocidal effect against this quarantine organism.
S C Arcos, M T Troya, L Robertson, F Llinares, M Conde, A Navas
Use of Acoustic Emission (AE) to detect activity of common European dry-woodboring insects: some practical considerations
2013 - IRG/WP 13-10803
Old house borer (Hylotrupes bajulus), Furniture beetle (Anobium punctatum), and Deathwatch beetle (Xestobium rufovillosum) are common dry-woodboring insects occurring throughout Europe. With the aim to prevent unnecessary use of biocidal products, to protect valuable wooden elements and objects from unwanted influences, and to have a more objective method, SHR has started to study the use of acoustic emission (AE) to assess activity of attack by these insects. This manuscript deals with the results of some experiments done in order to collect knowledge about the influence of (low) temperature or possible daily rhythms on the activity of the insects. Such knowledge is crucial for a trustworthy application of AE detection for European dry-woodboring insects in practice. Based on an 8-day-test with Hylotrupes with normal daily variation in temperature it is concluded that under these circumstances, temperature is the main influencing factor regarding insect activity. For individual larvae, phases of inactivity exist with a duration of up to 30 minutes. In practice, where probably more than one larva is present at one specific time, in the absence of AE events, measuring periods may need to be extended to at least these 30 minutes. With regard to minimum temperatures for detection, the insect species studied show small differences in behaviour at low temperature. Because the number of registered hits for all species shows a marked decrease at temperatures becoming lower than 10 °C, it is recommended that decisive assessments using AE for detection of activity of these dry-woodboring insects should be done at (wood) temperatures of 10 °C or higher.
J G M Creemers
Bioavailability of Bifenthrin and Fipronil against subterranean termites (Isoptera: Rhinotermitidae) in various soils
2013 - IRG/WP 13-10804
Present study was conducted to determine the toxicity and bioavailability of Biflex (Bifenthrin) and Fipronil (Phenyl pyrazole) termiticides against common termite species Heterotermes indicola (wasmann). Soil was collected from ten different areas of Lahore and was divided into sandy clay loamy (SLC) soil and sandy loamy (SL) soil after analysis. Laboratory bioassays (Topical application method and soil contact method) were conducted to determine bioavailability ratio of Biflex and Fipronil in each type of the soil. Based on calculated bioavailability ratios it was seen that Biflex was more bioavailable (0.888 in SCL soil and 0.765 in SL soil) to the target termites than Fipronil (0.459 and 0.302 in SCL and SL soil respectively). In topical treatment both termiticides showed highest mortality (25.0 ±0.00). In the same way in soil contact bioassay Biflex showed highest mortality rate (25.0 ±0.00 in SCL and 24.66±0.33 in SL soil) at 5ppm while Fipronil treatment showed moderate mortality (24.33±0.667 in SCL and 23.0±0.00 in SL soil) at same concentration. Regarding soil type both termiticides had more efficacies in sandy clay soil as compared to sandy soil. From statistical analysis it was observed that there was significant difference in the mortality as compared to control (P<0.005).
F Manzoor, P Mahnoor, B M Ahmed (Shiday)
The chemistry of wood degradation by Basidiomycetes studied in a van Krevelen diagram
2013 - IRG/WP 13-10805
The atomic composition ratios of decayed wood by Basidiomycetes are mapped in a van Krevelen diagram. It is shown that the wood residue after decay is chemically reduced, rather than oxidized. A previously developed and verified theoretical model for thermal wood modification, relating atomic composition ratios to moisture sorption and fungal resistance properties has tentatively been applied to wood modification by Basidiomycetes-attack. It is argued that some of the reaction mechanisms, activated by heat during thermal modification, may also become activated in wood under fungal attack.
W Willems, H Militz
Inhibitory extractives or nutrients? Mould growth on coated heartwood and sapwood of Pinus sylvestris and Gleditsia triacanthos
2013 - IRG/WP 13-10806
Sometimes mould fungi grow over weathered coated sapwood, whereas the coated heartwood is not colonised. Two factors may be responsible for these differences: Either the larger content of nutrients in the sapwood, or the content of biocidal extractives in the heartwood. In this study the factors for the difference in mould growth on coated heartwood and sapwood of Pinus sylvestris (Scots Pine) and Gleditsia triacanthos (Honey Locust) were studied. Prior to coating, the samples were leached with water for 14 or 30 days. The coated samples were then stored under favourable conditions for mould growth for 10 weeks. The coating used for the experiments is free of biocides, but shows no mould growth when applied on glass. For G. triacanthos the leaching procedure reduced the growth of mould both on sapwood and on heartwood. Nutrients migrating through the coating are obviously the dominant factor for mould growth on this wood species, whereas water-soluble inhibitory extractives in the heartwood are not relevant. For the sapwood of P. sylvestris the same tendencies were observed. No clear statements are possible for the heartwood of P. sylvestris.
D Lukowsky, N Buddruhs