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Laboratory investigations about the mobility of some inorganic wood preservatives in soils
1998 - IRG/WP 98-50101-22
Wood preservatives and components of wood preservatives leached from impregnated wood can enter the soil and thus contribute to the pollution of the groundwater. However, there is lack of understanding concerning the interacting parameters of wood preservative, leachate, soil and soil solution. To characterise of the behaviour of active ingredients and for the assessment of their environmental impact, leaching and diffusion processes are of basic interest with which the concentration of the relevant ions in the soil solution is determined by the reactivity of the ion, and by the type of linkage between the ion and the soil. The concentration and the specific behaviour of the ions in the solid and liquid phases can be investigated using different methods, e. g. using soil column tests (lysimeter). Several designs of lysimeter have been tested with water-soluble wood preservatives and the results been compared with the behaviour of wood preservative components leached from impregnated wood. As a result of the variability of the experimental set-up, of the wood preservatives and of the different soils tested, it became obvious that a standard procedure has to be developed. By means of some examples of varying results the similarities and differences of different procedures are discussed.
E Melcher, R-D Peek
Minutes of the Plenary Meetings held at the 20th Annual Meeting in Lappeenranta, Finland during 22-26 May 1989
1989 - IRG/WP 5352
Abstracts of some papers promised for IRG 22, Part II
1991 - IRG/WP 5370
Abstracts of some papers promised for IRG 22
1991 - IRG/WP 5368
Feasibility study for a dedicated pressure treated wood waste management system
2005 - IRG/WP 05-50224-22
For the creosote treated wood coming out of service, it has been estimated an amount of 200 000 t per year for the next twenty years, and 100 000 t per year afterwards. With a limited number of actors, mainly SNCF (as producer and as user), no importations, and available energy recovery options, it appears possible for setting a dedicated wood waste management system, if the SNCF agrees to. For the CCA treated wood, the amount of it coming out of service will increase and will be much more important, reaching about 400 000 t per year. For setting a voluntary dedicated waste management system might be much more difficult, because the importation is very important (about 50%), the margin of product low and the actors and users are numerous. Over the answer of the question on the feasibility for setting a dedicated pressure treated wood waste management system, this study must allow also define the priority actions to improve the pressure treated wood waste management.
C Cornillier, I Buda, E Heisel, G Labat
IRG 22 invitation
Annual Report 2021
2022 - IRG/WP 22-60499
IRG Documents 2022
2022 - IRG/WP 22-50513
Programme. The IRG53 Scientific Conference on Wood Protection
2022 - IRG/WP 22-60501
Plenary 2022 Agenda
2022 - IRG/WP 22-60500
Revised Budget 2022 (forecast May 2022)
2022 - IRG/WP 22-60502
2022 - IRG/WP 22-60503
2022 - IRG/WP 22-60514
Microbial decomposition of salt treated wood
1993 - IRG/WP 93-50001-22
Specialized microorganisms which are able to convert fixed inorganic preservatives from treated wood into water soluble components are investigated. A number of brown rot fungi like Antrodia vaillantii have been isolated from cases of damage and examined under unsterile conditions with CCA-, CCB-, CCF- and CC-treated wood at retention levels of at least 50% higher than recommended for wood in ground contact. Depending on the kind of fungus, preservative retention, wood particle size, culture conditions and duration Cr and As can be almost completely leached from the treated wood. Cu reacts with oxalic acid to a compound of limited water solubility.
R-D Peek, I Stephan, H Leithoff
The use of light organic solvents in industrial wood preservation - an environmental perspective
1995 - IRG/WP 95-50040-22
The paper examines the evolving regulatory environment concerning the use of hydrocarbon solvents in industry and, in particular, the European wood preserving sector. The implications of the proposed EU Directive on industrial solvent use are explained and possible responses to such regulation examined, including process modification, product changes and emission abatement, where necessary. The development of new solvent recovery technology for the wood preservation sector, as one response, is described in some detail.
G A Ewbank
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. Progress Report 22: Report on the conditions of specimens at Sekondi, Ghana after 60 months
1986 - IRG/WP 4123
The results of the third inspection of CCA and CCB treated test panels exposed at Sekondi, Ghana in June 1980 are presented. None of the panels still in test, i.e. panels of Pinus sylvestris treated with CCA at 3 and 10%, Alstonia scholaris treated with CCA at 10%, Fagus sylvatica treated with CCA at 10%, and Erythrophleum ivorense and Mitragyna stipulosa both treated with CCB at 10%, shows any external evidence of borer attack. X-radiography, however, shows that only Fagus sylvatica panels treated with 10% CCA remain completely free of attack. The attacking borers are teredinids.
F F K Ampong, N Asare-Nyadu
Dynamics of fungi colonization on the surface of Scots pine wood during natural weathering in different European climate zones
2022 - IRG/WP 22-10984
Wood The presence of fungi leads to biomaterial decay and/or changes in aesthetical appeal. The start of fungi colonization as well as the following growth on wood are primarily influenced by four factors: ambient temperature, moisture history of the object, access to oxygen, and intrinsic properties of the exposed wood, considered here as a source of nutrients for microorganisms. A prevalence of fungal spores in a close vicinity, combined with favourable environmental conditions are indispensable for the initiation of the growth of microorganisms. All the above factors are highly dependent on the local circumstances and especially climate conditions. It is important to understand the effect of weather on the diversity and distribution of endemic fungal communities in advance, to identify plausible remedies as related to the present global climatic changes. It is foreseen that the composition of fungal cultures as well as their growth kinetics on various wood substrates may evolve in the near future. The goal of this study was to investigate the relationship between specific weather conditions, representing diverse climate zones, on the occupancies and colonization dynamics of fungi/mould species. The test was performed on untreated Scots pine (Pinus sylvestris L.) wood samples exposed to natural weathering for 12 weeks from July to September 2021, in two locations: 1) Izola (Slovenia, 45°32'12.98"N, 13°39'42.98"E), representing the mild Mediterranean climate of southern Europe, and 2) Skellefteå (Sweden, 64°45'2.41"N, 20°57'10.04"E) representing Scandinavian or northern Europe climate zone. The local weather conditions recorded during the exposure period were used for modelling the growth kinetics. Fungi colonizing wood surfaces were manually collected from twin samples at each location, every second week, by swabs and cultured on nutrient media. The identification of fungi was performed visually according to the mycological keys of the detected genus. The presence of fungi was first noticed after 2 weeks of exposure. The majority of species detected were Ascomycetes from the genus Cladosporium, Aureobasidium, and Aspergillus. The combination of climatic parameters influences the compositions and colonisation of microorganisms on Scots pine wood. However, the obtained results showed fluctuations in the colonisation of the spores of culturable fungi. This might be the influence of other factors including geographic location, sensitivity of each fungal species to environmental factors, animals, plants, human activities, and pollutants that need to be taken in account.
F Poohphajai, O Myronycheva, O Karlsson, L Rautkari, J Sandak, A Sandak
Decay capacity and degradation patterns of Xylaria hypoxylon on different wood species
2022 - IRG/WP 22-10985
A host of physical and environmental factors may influence fungal decay including the wood substrate, temperature, moisture, oxygen, light, pH, and nitrogen. Understanding the effects of these factors on fungal decay is important for the effective utilization of wood decay fungi in biotechnological processes and for understanding the role of these organisms in global carbon cycling. The ascomycete Xylaria hypoxylon causes white rot of hardwoods, but remains relatively under-characterized. In this investigation, the decay capability of this fungus was studied using beech, hornbeam, oak and pine. Although Xylaria species are considered as causing white rot decay, Type II soft rot erosion was observed on hornbeam, Type I soft rot cavities were noted on beech, simultaneous rot was found on oak and selective rot on pine. Results indicated that both wood species and cell wall chemistry affected morphological decay patterns illustrating the relationships between fungal enzymatic capacity and wood cell wall structure/chemistry.
E Bari, G Daniel, A Singh, J J Morrell
Changes in topochemistry and mechanical properties of Beech (Fagus orientalis L.) by natural fungus infestation
2022 - IRG/WP 22-10986
Beech is one of the major hardwood species in Europe. It is, however, highly susceptible to fungal attack both in the fresh state and during the storage. Understanding the alteration in chemical and mechanical properties of beech wood during the initial degradation state can lead to improved raw material utilization. Therefore, UV-microspectrophotometer (UMSP) and High-Performance Liquid Chromatography (HPLC) were employed to study the chemical changes in beech (Fagus Orientalis L.) samples infested naturally by white rot fungi. The mechanical properties of infested beech were also determined and compared with the sound wood. The UMSP showed an apparent degradation in the region of the S3 and the S2 layers. HPLC analysis illustrated that catechin was the main component both in sound and infested beech wood. Considerable reductions in the mechanical strengths, bending properties and compression strength, were also apparent due to infestation.
H Sivrikaya, M Rehbein, F Divos, S Adamopoulos, R Hosseinpourpia
In Vitro Growth of the Basidiomycetes Physisporinus vitreus strains in various conditions in comparison with some white rot fungi
2022 - IRG/WP 22-10987
The paper has preliminary test results to select Pysisporinus vitreus fungal strains for further experiments in a large research project on copper tolerance of P. vitreus by chemotropic test, choice test, and agar plate toxicity tests and determination of the effect of various ions on oxalic acid secretion by these white rot fungi. In the project, it is also aimed to run fungal decay tests to determine nano and soluble-Cu tolerance of the test fungi and Cu depletion by the fungi. A myco-remediation process of nano and soluble-Cu-treated wood by the test fungi in liquid media is also planned to determine the effect of the ions on their remediation potential. Twelve P. vitreus and nine white rot fungal strains were tested to determine optimum growth conditions in both solid malt extract agar (MEA) or potato dextrose agar (PDA) plates and liquid (N-rich and standard) media. The growth media was also regulated to different pH degrees. Radial growth of the fungi was monitored for 12 days on the media. At the end of the incubation period, the mycelial biomass and the medium pH were also determined. Considering the growth and biomass production by the fungi, MEA at 5.6 as solid medium and the standard liquid media at 5.6 and 7 were determined as most suitable artificial media. In all cases, the media at pH 9 provided unfavorable conditions for fungal growth. P.vitreus FP71186, P.vitreus ME441, and P.vitreus P151 strains were selected for further steps of the project based on their growth rate, biomass production and their capability to lower pH levels.
E E Soytürk, S N Kartal
Chemical composition of agarwood of Aquilaria crassna Pierre ex. Lecomte induced by Basidiomycetes from French Guiana
2022 - IRG/WP 22-10988
Aquilaria trees subjected to stress induce the formation of a transformed wood named agarwood. The formation of agarwood is a plant defense mechanism that occur in complex interactions with environmental microorganisms. Agarwood chemical compounds are mainly chromones and oxygenated sesquiterpenes such as eudesmol, agarospirol, jinkoh-eremol and valerianol, which are valued in perfumery. Its derivatives, notably the essential oil are therefore expensive. Agarwood essential oil costs 5,000 to 10,000 US $ per kg. Because of this important value and the scarcity of production from the wild, operators are planting Aquilaria and implementing various methods to induce agarwood. Many of these methods are deleterious for trees and even can alter the chemical composition of the essential oil. In this context, a consortium of farmers from French Guiana and scientists and from Centre de cooperation Internationale en Recherches Agronomiques pour le Développement (CIRAD) are developing the Aquil@Guyane project. This project aims at cultivating Aquilaria trees in French Guiana to produce agarwood of controlled chemical composition, respecting the biology and ecology of trees. In this frame we have tested the inoculation of trees with cubic and fibrous rot fungi to induce agarwood development in tree. Fungal strains used in this experiment have been isolated in the vicinity of Guianese Aquilaria plantations. Selected strains have been cultivated on wood test-sticks; infected sticks were then place in holes made with a drill in the trunks of Aquilaria. The yield of agarwood and chemical compositions of essential oils extracted from the so obtain blackened wood have been analyzed enabling to compare the different treatments. First, we evidence that the controlled inoculation of Aquilaria tree with selected fungal strains results in the production of agarwood and thus essential oils. The quality, in terms of composition of essential oils obtained among treatments was distributed between reference white wood and agarwood. The fibrous rot fungi were the most effective in terms of agarwood development and quality and yield of essential oils.
C Zaremski, M Ducousso, C Andary, G Michaloud, C Menut, A Zaremski, N Amusant
Assessing the Performance of Wood-based Materials Exposed to Termite Risk – A New Experimental Approach
2022 - IRG/WP 22-10989
Termites are able to degrade a large number of building materials including wood, wood-based panels, biobased insulation, and polymers. The risk for a material of being degraded by termites depends on its composition, on its accessibility, and also on the behavior and the biology of the termite species considered. Within the EU project Click Design, we investigated the durability, under laboratory conditions, of different wood species and building materials commonly used in construction in Europe (oak, chestnut, wood-based panels, CLT, modified wood) or currently under development (new modification process, bio-based materials) when exposed to attacks by the European subterranean Reticulitermes termite. We also assessed their performance by adapting standardised test protocols and using experimental approaches specifically developed for this study (pairwise and multiple-choice test, doubled-time exposure). The results demonstrated that the materials classified as “moderately durable” against different species of termites (R. flavipes, R. grassei and R. lucifugus) are not a suitable source of food for these insects if no other food is available simultaneously and cause high termite mortality in forced-feeding conditions. In conditions of choice-test where another source of food is available, these materials are first explored by termites but then quickly neglected. Durability and performance are distinct properties which should be evaluated together. The recommendations for end-uses of wood-based materials (indoor or outdoor use, proximity to the ground, etc.) should take into account both their class of durability and their expected performance in real-life situations. The objective of this approach is to better promote the use of moderately durable materials in situations where termite risk can be monitored and/or controlled.
Antifungal and antitermite activities of acetonic extractives from Cedrus Atlantica heartwood
2022 - IRG/WP 22-10990
Cedrus atlantica is a woody species present in France, which in a context of climate change can be privileged in the next years. In addition, this woody species presents great ecological and socio-economic interest as it is mainly recognized for its durable timbers and its essential oil presenting some interesting chemical properties. Therefore, the studies of its heartwood formation and properties of its extractives are interesting, spite of very few studies have been conducted till now. The radial repartition of water/acetone extractives within the tree (bark, sapwood, transition wood, outer heartwood and inner heartwood), at different tree height levels, were screened. HPLC analyses were performed, especially to characterized flavonoid compounds of these extractives fractions. The radial variation of the extractive composition obtained, highlighted the phenomenon of heartwood formation. Hypotheses on the metabolic pathways involved in the heartwood formation process of cedar wood were suggested, especially based on the occurrence and the radial evolution of catechin, taxifolin and flavan compounds. Then, the antifungal and anti-termite activities of the extracts were tested. The water/acetone extractives from Cedrus atlantica showed a strong repellent activity against termites and a moderate antifungal activity against crops and fruits pathogens. Thus, the results show a possible valorisation of the extractives of the Atlas cedar, as wood preservatives and/or as biocontrol products against pathogens of lignocellulosic agricultural crops.
R Dijoux, R Ducruet, E Kieny, D Aznar, C Cayzac, L Bidel, C J Allemand, K Candelier
The effect of sapwood and heartwood differences on durability of short rotation teak wood
2022 - IRG/WP 22-10991
Short rotation teak has been developed to overcome the limited supply of long rotation teak. The aim of this study was to investigate the effect of sapwood and heartwood differences on durability of short rotation teak. The following basic properties were studied: extractive content, dimensional stability (volumetric swelling and water uptake), decay resistance, and termite resistance. The results show that the extractive content of heartwood (7,41 %) was higher than sapwood (5,23 %). The main compounds in the extractive content of heartwood were lapachol and 9,10-anthracenedione; meanwhile the main compounds of sapwood were mostly single sugars and derivatives. The volumetric swelling and water uptake values of sapwood were higher than heartwood, indicating that sapwood had lower dimensional stability compared to heartwood. Weight losses of sapwood due to decay by Coriolus versicolor (CV), Pycnoporus sanguineus (PS), and Coniophora puteana (CP) were in the average of 25%, 15%, and 1.5%, respectively. However, weight losses of heartwood exposed to the same decaying agents were close to 0%, which categorized the heartwood durability to class 1 (very durable). The extractives present could determine the good durability of short rotation teak wood against fungi. The low weight loose of heartwood exposed in field test to subterranean termites indicated good durability of heartwood. Sapwood had lower quality especially in dimensional stability and durability restricting its utilization for both indoor and outdoor applications. Therefore, sapwood should require certain attention and treatment, especially for wood exposed to outdoor conditions.
R Martha, M Mubarok, F O Akong, B George, C Gérardin, S Dumarçay, I S Rahayu, I Batubara, W Darmawan, P Gérardin
Natural durability and moisture dynamics of commercially important European wood species after weathering
2022 - IRG/WP 22-10992
Wood is a frequently used material. Timbers’ mechanical properties, particularly its favourable strength-to-mass ratio, make them suitable for many uses. Current environmental awareness has led to its renewed importance as a building material. However, wood is susceptible to decay that severely affect its outdoor performance. This study investigated how weathering affects the natural durability and moisture dynamics of six commercially important European wood species. Defect-free specimens (1.5 cm × 2.5 cm × 5.0 cm) were exposed to natural weathering for 9, 18, and 27 months or artificial accelerated weathering. The exposure corresponded to the 3rd use class (above ground, uncovered, frequent wetting). The moisture performance of control and exposed samples was then determined according to the Meyer-Veltrup approach. The same samples were also exposed to the brown-rot fungus Gloeophyllum trabeum for 16 weeks. The respective wood species were classified into durability classes according to EN 350, and the relative resistance dose (Drd rel) was calculated. Weathering reflected in decreased relative resistance dose, which can be attributed to leaching of biologically active extractives, altered surface morphology, and increased permeability. The most significant decreases were observed in the heartwood of sweet chestnut, Scots pine, and European larch. Moreover, a good correlation can be observed between mass loss after weathering, and mass loss caused by G. trabeum, especially in the heartwood of sweet chestnut was determined.
E Keržič, M Humar