Your search resulted in 47 documents. Displaying 25 entries per page.
Co-operative research project on L-joint testing. Sampling after 8 months exposure
1983 - IRG/WP 2208
It was anticipated in Document No IRG/WP/2192 that exposure of L-joints by the European co-operators would take place on 1 April 1983. Where L-joints were exposed at this time, sampling after 8 months exposure is due on 1 December 1983. The present document draws attention to relevant previous documents which describe the sampling methods to be adopted. It also provides Tables for recording the results.
J K Carey, A F Bravery
Co-operative research project on L-joint testing. Progress report to March 1988
1988 - IRG/WP 2315
Further sets of data received from CTFT (France), BAM (Germany) and PRL (UK) after 46-48 months exposure and STU (Sweden) after 22 months exposure are presented and discussed in conjunction with data reported previously. Colonisation and attack of the L-joints has progressed with increasing exposure period. The new data are generally in agreement with those presented previously and the major difference between Institutes continues to be one of rate of colonisation rather than any relative difference in performance of the treatments. Overall 0.5% TnBTO 1 min dip treatment is providing least protection followed by 1.0% TnBTO 1 min dip treatment. The double vacuum treatments continue to provide better protection than the dip treatments; there are now indications that 0.5% TnBTO double vacuum treatment is less effective than 1.0% TnBTO.
J K Carey, A F Bravery
Co-operative research project on L-joint testing. Progress report to March 1984
1984 - IRG/WP 2211
Each participant was intended to expose L-joints in the main trial on 1 April 1983 and the first sampling, after 8 months exposure, was to be undertaken on 1 December 1983. Some participants have had to vary this schedule. Results are presented from CTFT (France) and PRL (United Kingdom). These show a greater effectiveness by the double vacuum treatments compared with the 1 minute dip treatments. However, results from the two locations differ particularly in the incidence and type of Basidiomycetes isolated.
J K Carey, A F Bravery
Co-operative research project on L-joint testing. Sampling after 18 months exposure
1984 - IRG/WP 2233
In September 1983, Document No: IRG/WP/2208 was distributed giving guidance on sampling after 8 months exposure (due 1 December 1983 for those L-joints exposed on schedule on 1 April 1983), and including tables on which to record the test results. No major problems have been notified to Princes Risborough Laboratory concerning the sampling method. It is therefore proposed that the next sampling, after 18 months exposure for those L-joints exposed on 1 April 1983, should proceed using the same methodology, on 1 October 1984.
J K Carey, A F Bravery
Co-operative research project on L-joint testing. Progress report to March 1986
1986 - IRG/WP 2272
Further sets of data received from CTFT (France) after 18 months exposure, BAM (Germany) after 18 months exposure, STU (Sweden) after 9.5 months exposure and TI (Denmark) after 12 and 17.5 months exposure are presented and discussed in conjunction with data previously reported. The new data are generally in agreement with those presented previously and indicate the major difference between the co-operating Institutes is one of the rate of colonisation rather than any relative difference in performance of the treatments. Overall 0.5% TnBTO 1 min dip treatment is providing least protection followed by 1.0% TnBTO 1 min dip. Both double vacuum treatments are providing better protection with little difference between 0.5% and 1.0% TnBTO.
J K Carey, A F Bravery
Co-operative research project on L-joint testing. Progress report to March 1985
1985 - IRG/WP 2236
It was originally intended that each participant would expose L-joints in the main trial on 1 April 1983 with the first sampling at 8 months (1 December 1983) and the second sampling at 18 months (1 October 1984). In the event, some participants have had to vary this schedule. Results after the first sampling have been received from CTFT (8 months), BAM (12 months) and Sipad-IRC (8 months) and after the second sampling from PRL (18 months) and Sipad-IRC (17 months). These, together with data presented previously, show a good correlation between gradual increases in permeability and the increasing incidence of Basidiomycetes. Both double vacuum treatments are proving more effective than the dip treatments; at the present stage 1.0% TnBTO appears to be no more effective than 0.5% TnBTO. The major difference between Institutes appears to be the rate at which colonisation and attack occurs rather than in the patterns of colonisation.
J K Carey, A F Bravery
Co-operative research project on L-joint testing. Sampling after 4 years exposure
1987 - IRG/WP 2274
In September 1983, Document No: IRG/WP/2208 was distributed giving guidance on sampling after 8 months exposure and including tables on which to record the test results. Similarly in September 1984, Document No: IRG/WP/2233 was distributed concerning sampling after 18 months exposure. No major problems have been notified to Princes Risborough Laboratory concerning the sampling method. It is therefore proposed that the last sampling, after 4 years exposure for all those L-joints exposed in 1983, should proceed using the same methodology, during April or May 1987 as agreed at IRG-17 in Avignon.
J K Carey, A F Bravery
Update on lab and field test results for polymeric alkylphenol polysulfide treated wood
2002 - IRG/WP 02-40240
The possibility of using Polymeric Alkylphenol Polysulfide (PXTS) as a wood preservative has been undergoing evaluation in our laboratories for the past four years. Various formulations prepared from this compound have been tested and found to be effective against wood decay fungi and insects in field stakes after 42 months exposure. In accelerated soil bed tests, PXTS has been shown to be considerably more effective than creosote against both soft-rot and basidiomycete decay fungi. PXTS has also been shown to be effective against marine organisms and after 18 months exposure appears to have about the same efficacy as creosote. Preliminary treatment trials indicate that southern pine can be readily treated by the empty cell process
J Goswami, A Abramson, R Buff, D D Nicholas, T Schultz
Short term preconditioning of preservative-treated wood in soil contact in relation to performance in field trials
2000 - IRG/WP 00-20185
The effect of pre-exposure to primary colonising micro-organisms on preservative-treated wood, prior to a basidiomycete decay test, was determined by preconditioning in two soil types. Scots pine EN 113 blocks treated with 3 model systems (a triazole, a copper quaternary compound and a copper boron triazole) were leached according to EN 84 and subjected to 6 weeks and 8 weeks burial in either John Innes no. 2 (a loam-based horticultural compost) or soil from the Simlångsdalen field site in Sweden. The samples were then tested according to the method described in EN 113. Selective isolations were also performed after soil exposure and compared with those from a longer term field trial. Preconditioning lowered the effectiveness of the 2 copper containing preservatives. Some effect of soil pre-exposure could be noted with the triazole but this was limited. The fungal isolations from preconditioned EN 113 blocks and field exposed stakes were a similar mixture of soft rot and mould fungi. Bacteria were commonly isolated from the preconditioned wood. The role of these micro-organisms in the modification of the preservatives is currently being investigated.
S Molnar, D J Dickinson
Natural durability and basic physical and mechanical properties of secondary commercially less accepted wood species from Brazil
2002 - IRG/WP 02-10451
The natural durability towards basidiomycete fungi and termites of several secondary timber from Brazil (Vatairea sp., Hymenolobium sp., Inga sp., Manilkara sp., Caryocar sp., Terminalia sp., Apuleia sp.) has been evaluated according to the EN 350-1. Some basic physical and mechanical properties (density, shrinkage, hardness, colour, static strength in flexion and compression) were also measured according to the appropriate standards. The results given in this paper could help in promoting the utilization of these timbers for certain end-uses.
M-F Thévenon, A Thibaut
Questionnaire for Volume 2 of the basidiomycete monographs
1985 - IRG/WP 1254
12 monographs of wood destroying basidiomycetes were published in volume 1. Volume 2 includes the following 17 basidiomycetes: Antrodia serialis, Chondrostereum purpureum, Climacocystic borealis, Fomitopsis pinicola, Hyphoderma tenue, Lentinus degener, Lentinus squarrulosus, Paxillus panuoides, Phellinus contiguus, Poria xantha, Pycnoporus sanguineus, Rigidoporus vitreus, Serpula himantoides, Sistotrema brinkmannii, Stereum sanguinolentum, Trametes corrugata
Report on the status of collaborative experiments within the Sub-group on Basidiomycete tests
1983 - IRG/WP 2194
This report summarises the results of co-operative work carried out within the Sub-Group on Basidiomycete tests up to December 1982. The principle findings are recorded in the Conclusions Section. Work intended between IRG-13 in Turkey and IRG-14 in Australia is cited under Future Programme. An Annex provides a response sheet for existing and new participants to notify their contributions.
A F Bravery
Sub-group on Basidiomycete tests: Responses to proposals for programme of work
1980 - IRG/WP 2137
A F Bravery
The effect of storage or simulated internal use on the durability of wood based panels to decay fungi
1997 - IRG/WP 97-20106
Wood based panels such as particleboard and medium density fibreboard are experiencing a steady increase in use, in areas from structural to decorative applications. Understanding the "natural" durability of these panel products against basidiomycete fungal decay is therefore of great importance. Various methods have been proposed or are under development to test the durability/susceptibility of various panel products to decay. Our research has shown that if the fungal exposure methods detailed in the current European pre-standard (DD-ENV 12038:1996) are used to test boards fresh from manufacture, the susceptibility ratings observed are significantly lowered by the buildup of inhibitory substances in the test vessels. The effects of storing the boards before testing, in order to remove this effect have been studied with repeat biological tests carried out at intervals of 6 months. Our results show that even after 6 months storage the effect is reduced but not totally removed. The time after manufacture and the storage conditions are clearly significant variables affecting the "durability" of test specimens taken from the boards and therefore the incorporation of an appropriate preconditioning stage into the test is essential so that the effect is avoided.
S F Curling, R J Murphy, J K Carey
Sub-group on Basidiomycete tests: Proposals for Sub-group programme of work
1979 - IRG/WP 2127
During the IRG 10 Meetings in Peebles, Scotland in September 1978, it was resolved to establish within Working Group II a sub-group on testing wood preservatives against basidiomycete fungi. The terms of reference and scope of the sub-group's activities were to be determined by consensus among members who registered an interest. Dr A F Bravery (PRL, UK) was asked to act as co-ordinator. During the course of the Peebles Meeting the following members registered their intention to participate: Dr D Aston (UK), Dr C Coggins (UK), Mr G Fahlstrom (USA), Professor D French (USA), Professor C Jacquiot (France), Mr B Jensen (Denmark), Dr A Ofusu-Asiedu (Ghana), Miss J Taylor (UK). Since there was insufficient time to convene an inaugural meeting in Peebles the present paper has been prepared as a basis for discussions and to facilitate initiation of active collaboration. It is hoped that members will offer individual comment in order to define the desirable scope of the sub-group's work and to refine ideas for collaborative or co-ordinated experimental work.
A F Bravery
Practical testing of wood preservatives to prevent weathering damage and infection by micro-organisms on spruce and pine
1989 - IRG/WP 3530
Brush application, is generally used to prevent wooden window frames from decay caused by influence of weathering and fungi. Accordingly 10 boards of pine (Pinus sylvestris) and spruce (Picea abies) were treated with 10 commercially used wood preservatives. The efficiency of fungicides by using chiptest and blue stain test (EN 152), the effectiveness against weathering as well as the course of colonization of microfungi were measured on boards, that had been hurted by sawing. Results after one year's exposure showed that neither the normally required amount of 250 ml/m² nor the effective depth of penetration of the fungizidal equipment had been realized by using brush application. The smaller the permeability of the coating system, the more likely ideal conditions for the growth of fungi (e.g. basidiomycetes) are provided, answering hurtings of the coating and moisture contents of more than 30%. The variety of fungi (on pine 32 and on spruce 17 species) can be a result of anatomical differences and distinguished compounds of the wood species. After 24, respectively 36 weeks of exposure the frequent occurrance of basidiomycetous yeasts (Cryptococcus albidus, Rhodotorula mucilaginosa), blue stain fungi (Aureobasidium pullulans, Hormonema dematioides), Epicoccum nigrum, Alternaria alternata and Phoma species was noted.
R Gründlinger, O Janotta, H Melzer, K Messner
An experimental method to simulate incipient decay of wood by basidiomycete fungi
2000 - IRG/WP 00-20200
At very early stages of decay of wood by basidiomycete fungi, strength loss can be measured from wood before any measurable weight loss. Therefore, strength loss is a more efficient measure of incipient decay than weight loss. However, common standard decay tests (e.g. EN 113 or ASTM D2017) use weight loss as the measure of decay. A method was developed that allowed progressive removal of samples so that all stages of colonisation and decay could be monitored by strength testing, weight loss determination and chemical analysis. Our results indicated that substantial and rapid decay (90% strength loss and 40% weight loss after 12 weeks) of southern pine by brown rot fungi was possible using the method. Our results also demonstrate a direct relationship between strength loss and weight loss and suggest a quantitative relationship between strength loss and chemical composition (hemicellulose sugars) during incipient decay of southern pine by basidiomycete fungi.
S F Curling, J E Winandy, C A Clausen
Effect of light and ventilation condition on the rate of wood decay by the brown rot basidiomycete, Tyromyces palustris
1991 - IRG/WP 1517
Effect of light and the ventilation conditions of incubation jars on the wood decay by Tyromyces palustris (Berk. et Curt.) Murr. FFPRI 0507 was investigated. Under no irradiation of light, the ventilation conditions gave extensive effect on mass loss of the test pieces when the culturing was performed with culture medium designated in Japanese Industrial Standard (JIS) A 9302 (Medium A; glucose 4.0%, malt extract 1.5%, peptone 0.3%). On the other hand, no such kind of effect for ventilation conditions was recognized under light conditions, and the wood decay by the fungus accelerated by additional light irradiation of a considerably small intensity. Next, we investigated the relationship between light and the culture medium composition during the wood decay by the fungus. It was found that almost equivalent mass loss occurred after 60-90 days of cultures when the culturings were performed under light-shield conditions with medium A, the culture medium designated in Japan Wood Preserving Association (JWPA) standard No.1 (medium B; malt extract 2.0%, peptone 1.0%), and another culture medium diluted medium B by two times (medium C). Under the irradiation of light, the mass loss on the cultures in medium B and C was markedly less than that in the same media under no irradiation conditions. These results suggested that effect of light on the wood decay by Tyromyces palustris depended on the concentration of glucose in the culture medium. Further, we also investigated the activities of several extracellular and cell wall bound enzymes in wood meal medium contained medium A. From our experimental results, the activities of cellulase (b-1,4-glucan 4-glucanohydrolase, E.C. 184.108.40.206) and mannanase (b-1,4-mannan mannanohydrolase) depended on light irradiation during the wood decay and these enzyme activities may give extensive effect on the mass loss by Tyromyces palustris.
T Suzuki, M Higaki
Molecular analysis of the basidiomycete Coniophora puteana
1992 - IRG/WP 92-1534
Sodium dodecylsulphate polyacrylamide gel electrophoresis and Western Blotting, using a polyclonal antiserum produced against a whole cell extract of Coniophora puteana, were used to analyse the major proteins and antigens of the wet rot organism Coniophora puteana. The macromolecule profiles of this organism were different from other members of the Coniophora genus and from a set of unrelated organisms. However the profiles for Coniophora marmorata and Coniophora arida were more like that of Coniophora puteana than other organisms analysed. Analysis, by SDS-PAGE of exoproteins indicated differences between members of the Coniophora genus but, whilst there were some intra-species differences overall profiles were similar for all isolates of Coniophora puteana tested. Some cross reactivity of the Coniophora antiserum was noted, both in Western Blotting and in enzyme immunoassay and whilst the antiserum was produced against liquid culture grown organism it was able to detect Coniophora puteana when extracted from infected wood blocks. Furthermore, unlike some other basidiomycetes analysed serum components did not bind nonspecifically to Coniophora puteana.
H E McDowell, D Button, J W Palfreyman
Délavabilité de bois ronds traités avec un sel CCA dans des conditions réelles de stockage. Incidence pratique de la fixation accélérée par étuvage. Impact effectif sur l'environnement
1993 - IRG/WP 93-50001-23
Un essai de terrain a été organisé pour mesurer concrètement, dans des conditions aussi proches que possibles des conditions réelles de terrain, les pertes effectives en produit de traitement lorsque le bois traité est soumis à des intempéries. L'essai a été conduit sur des bois ronds (poteaux), traités en autoclave par procédé Bethell avec un sel CCA de type C, avec comme finalité l'évaluation de la nature et des quantités de composés délavés en pratique, pour évaluer ainsi leur impact réel sur l'environnement au niveau du site de traitement. Compte-tenu des propriétés fixantes de ce type de produit, il était interessant d'identifier ces pertes à différents stades de la fixation, ainsi qu'après fixation compléte. Utilisant également les divers travaux et constats disponibles à ce jour sur les possibilités d'accélérer la fixation par l'étuvage, nous avons voulu observer et quantifier cette amélioration dans les mêmes conditions de terrain. Cet essai a été organisé et exécuté conjointement par le CTBA et la société FRANE BOIS IMPREGNES. Il conduit à 3 constatations principales: - Les pertes pratiques sont quantitativement nettement moins importantes que celles obtenues à partir des méthodes et échantillons de bois utilisés en laboratoire. - A l'issue et surtout au cours de la fixation les divers métaux se comportent de façon très différente, et on peut penser que la nature de la formulation a une importance notable sur ce comportement, même si dans tous les cas les quantités concrètement délavées restent faibles. - L'éuvage en sortie de traitement et dans des conditions adaptées permet d'obtenir spontanément, un résultat analogue à celui obtenu par un cycle de fixation traditionnel.
M Rayzal, F Larroze
A survey of the incidence of decay in copper-chrome-arsenate treated trellis support posts used in horticulture in New Zealand
1984 - IRG/WP 1225
Copper-chrom-arsenate treated softwood posts used as trellis support structures in 5 major horticultural districts of New Zealand were systematically examined for presence of decay. Principal crops on properties examined were grapes and kiwifruit; a minority of properties grew hops, boysenberries, and dwarf apples. Occurrence and severity of decay were variable within specific age classes of posts on individual properties and also between properties in the same region which had posts of similar age. Incidence of decay was higher in posts set in soils which were highly moisture retentive than in posts in drier areas or set in freely draining soils. Cross-sectional size and age of posts showed little correlation with frequency of severe decay, although the percentage of posts free of decay increased with decreasing age.
M E Hedley, J A Drysdale
Incidence of soft rot in creosoted poles
1992 - IRG/WP 92-1554
A further population of creosote-treated poles has been assessed for the occurrence of soft rot, as a continuation of work reported in IRG Document No. IRG/WP/1368. The outer 1 cm of each core was assessed microscopically and graded for the presence of soft rot cavities in the wood cell walls; with further assessments taken at a consecutive 1cm interval for cores showing positive findings. Following this assessment each core was cultured on microbiological media in an attempt to isolate potential causative organisms and correlate their presence with the occurrence of soft rot cavities in the wood cell walls. The results indicate that a number of fungi may be important, either in causing soft rot decay or in creating the conditions necessary for such decay to occur. Of these, Hormoconis resinae seems to be particularly important. This fungus was found populating poles at a rate of 68% overall. Further work has also been undertaken, using gas chromatography and gas chromatography coupled with mass spectroscopy, to establish the amount of creosote present, its chemical composition in poles and to correlate this data with that for soft rot cavitation and microbiological assay.
D J Dickinson, P W McCormack, B Calver
Extracellular substance from the white rot basidiomycete Irpex lacteus involved in wood degradation
1992 - IRG/WP 92-1571
Cellulases, phenol oxidase, and a substance that both produced and reduced H2O2 were isolated from cultures containing wood or glucose on which the white-rot fungus Irpex lacteus was growing. The rate of wood degradation by the fungus with different amounts of glucose in the medium was measured. More of the substance that produced and reduced H2O2 was found extracellularly in cultures containing wood than in cultures containing glucose. The extent of one-electron oxidation activity of the extracellular substance was correlated with that of the wood-degrading activity, but the extent of phenol oxidase activity was not. The extracellular substance catalyzed the hydroxylation of phenol to hydroquinone and catechol in the presence of H2O2 or of NADH and O2. The substance seemed to be a glycopeptide containing Fe(II) and its molecular weight was very low.
H Tanaka, T Hirano, G Fuse, A Enoki
The high decay resistance in the sapwood of the naturally durable Malaysian hardwood Belian (Eusideroxylon zwageri)
2001 - IRG/WP 01-10410
It has long been assumed that the observed natural durability of the heartwood in certain timbers is perhaps associated with a relatively lower decay susceptibility also of the sapwood of these species. While the heartwood of Belian is reputedly highly decay resistant among the tropical hardwoods of Southeast Asia, laboratory decay tests reported in this paper have also confirmed the high decay resistance of the sapwood of this timber species. The sapwood of Belian is found to be resistant to decay by soft rot (Chaetomium globosum), white rot (Pycnoporus sanguineus & Coriolus versicolor) and brown rot (Poria sp. & Gloeophyllum trabeum) fungi after 12 weeks of decay testing, sustaining <2% mass loss, equivalent to that in its heartwood. The reference sapwood species Rubberwood (Hevea brasiliensis) and the heartwood of Kempas (Koompassia malaccensis) sustained significant mass losses from decay of up to 59% and 17%, respectively. Microscopic observations of Belian sapwood revealed extensive proliferation of extractives in the lumina of various cell types showing a pattern of extractive distribution similar extent to that in the heartwood tissues, although the extent of cell filling by extractives was not quite as high as for the heartwood. It is plausible that the inherent wood extractives deposited in the cells confer the same degree of anti-fungal properties to both the heartwood and sapwood of Belian.
A A H Wong, A P Singh
The effect of soil pre-exposure on the results of laboratory Basidiomycete testing
1991 - IRG/WP 2385
Scots pine sapwood blocks were treated with several concentrations of copper chrome arsenic (CCA), copper chrome boron (CCB) and a copper modified quaternary ammonium compound (CMAAC). Leached and unleached samples were exposed in a basidiomycete monoculture test using Coniophora puteana, a copper tolerant brown rot. Prior to testing half of the blocks were buried in unsterile soil for 4 weeks. The soil pre-exposure had little effect on the performance of the CCA and CCB treated samples against the brown rot but the performance of the CMAAC treated samples improved greatly
S M Gray