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Supply of wooden transmission and telephone poles in Tanzania: Problems and possible solutions
1987 - IRG/WP 3424
The eucalypts which have been used widely for utility poles for more than 30 years have dwindled remarkably from traditional supply areas. Consequently, pole-using authorities are considering importing poles from abroad. This alternative is considered unrealistic and costly. The aims of this paper are: - to dispel fears of pole scarcity and to show that an abundant resource of a variety of tree species, consisting of both hardwoods and softwoods, considered suitable for poles, is available; - to point out obstacles that hinder the full utilization of this natural and renewable wealth; - and to suggest workable solutions to the pole supply problems.
K K Murira, S A Diwani


Influence of different fixation and ageing procedures on the leaching behaviour of copper from selected wood preservatives in laboratory trials
2003 - IRG/WP 03-20264
The paper focuses on the role of different parameters, such as fixation, sample size, wood species, and leaching in internationally standardized ageing procedures for wood preservatives from Europe, Japan and the United States. The leaching protocols used were EN 84, JIS K 1571 and AWPA E11 protocols. The wood species were Scots pine, Sugi and Southern Yellow Pine respectively. Three types of commercially important copper-based wood preservatives were used as model formulations, namely copper/copper-HDO, ammoniacal copper/quat and CCA. The most important factors determining the extent of copper leaching in the different lab trials were the sample size (volume/surface ratio) and the fixation conditions prior to leaching. On the other hand, the wood species and the leaching protocol itself were found to have only minor influence on the copper leaching rate in the test methods included in this study.
J Habicht, D Häntzschel, J Wittenzellner


Phoracantha semipunctata Fab. dans le sud-ouest Espagnol: Lutte et dommages
1985 - IRG/WP 1250
L G Tirado


Trend in entomology of wood in use and in storage in Nigeria
1978 - IRG/WP 180
The current and potential impact of biotic agents of wood deterioration in Nigeria is reviewed, with emphasis on the insects and marine borers, their recognition and mode of damage. Some essential areas have no doubt been neglected and these are highlighted, while future lines of approach are outlined.
M O Akanbi


Field tests out of ground contact in France: Definition of the test procedure and preliminary results after 18 months
1981 - IRG/WP 2161
M Fougerousse


Studies on the infestation behaviour of the powder-post beetle Lyctus brunneus (Steph.) and its physical control in the wood yards of the Caspian forests of Iran
1985 - IRG/WP 1271
Lyctus brunneus (Steph.) is a pest which has not been previously thoroughly studied in Iran. It severely attacks Iranian hardwoods, especially those used in wooden houses and that have not been treated. Research work was necessary to determine the natural resistance of the most important timber species in Iran against this insect.
P Niloufari


Wood-destroying insects found in the Eastern Black Sea sub-region of Turkey
1982 - IRG/WP 1153
The Eastern Black Sea subregion has important forest resources. The settlement areas are scattered at the countryside. That's why a good deal of wood and timber is used in the construction of buildings without sufficient protective measures in the rural areas. In the forests and rural buildings 52 wood-destroying insect species have been specified 35 of which are new in this subregion and 14 are new in Turkey.
O A Sekendiz


Blue stain in timber in service. Results of co-operative tests to compare different artificial weathering systems 1981-82
1983 - IRG/WP 2193
The paper describes results of the third phase of co-operative laboratory experiments comparing the effects of different artificial weathering systems on chemicals to control blue-stain in service. Atlas, Xenotest and Marr equipments are shown to give essentially the same results for 5 of the 6 chemicals tested.
A F Bravery, D J Dickinson


Preventive action against fungal decay: A comparative experiment on the effects of natural and artificial infection of wood by Basidiomycetes
1981 - IRG/WP 2160
M Fougerousse


The true dry rot fungus (Serpula lacrymans) found in the wild in the forests of the Himalayas
1993 - IRG/WP 93-10002
J Bech-Andersen, S A Elborne, F Goldie, J Singh, B Walker


Testing wood in ground contact: An artificial soil
1977 - IRG/WP 280
This document is an interim report on the development of the artificial soil medium. It includes some information on the relationship between soil, wood and water which is of relevance in testing.
E F Baines, D J Dickinson, J F Levy


Influence of abiotic factors on the production of Basidiocarps by lignocellulolitic Hymenomycetes from native forest and plantations of Pinus elliottii Engelm in the Fontes do Ipiranga State Park, São Paulo, Brazil
1991 - IRG/WP 1469
A report on the influence of abiotic factors on the production of basidiocarps by lignocellulotic Hymenomycetes of native forest and Pinus elliottii. It was concluded that the climatic conditions (temperature, humidity, microhabitat) and the decay stage of the logs affected the production of basidiocarps by Hymenomycetes.
M Aparecida de Jesus


A comparison between methods for evaluating the water repellency of wood
1989 - IRG/WP 2328
Wood specimens treated with a number of water repellent formulations have been tested for their water repellency according to four laboratory test methods, based on weight increase, swelling and contact angle measurements, in order to assess the degree of agreement between the different methods. Treatments representing formulations with a wide range of water repellent efficiency were tested both initially and after simulated weathering. A ranking of the water repellent treatments shows deviations between the different test methods although the general agreement is relatively good. Contact angle measurements are less appropriate due to a poor repeatability. The development of new standard test methods where the long-term performance or water repellent treated wood is evaluated by a weathering procedure is of great importance.
R Nussbaum


Lignocellulotitic Hymenomycetes from native forest and Pinus elliottii Engelm in the Fontes do Ipiranga State Park, São Paulo, Brazil
1991 - IRG/WP 1468
Results show a distinct microflora for each forest type. A total of 9 families, 45 genera and 67 species were distributed among the two forest ecosystems were studied. Antrodiella, Auricularia, Grammothele, Steccherinum, Stereum and Trametes were found only in the native forest, where Antrodiella hydrophila (Berk. & Curt.) Ryv., Grammothele sp, Phellinus gilvus (Schw.) Pat., Rigidoporus microporus (Fr.) Overeem, Schizopora flavipora (Cke.) Ryv. and Trametes versicolor (Fr.) Pilat. were the most frequent species. Logs associated with Dentipellis dissita (Berk. & Cke.) Mass., Hydnochaete badia Bres., Lentinus calyx (Speg.) Pegler, Lentinus nigroosseus Pilat., Phellinus gilvus (Schw.) Pat., Rigidoporus lineatus (Pers.) Ryv., Steccherinum reniforme (Berk. & Curt.) Banker., Tomentella pallida (Rick) Penteado, Trametes versicolor (Fr.) Pilat., showed rapid decay during the sampling period. The Pinus elliottii plantation demonstrated specificity for Cladoderris dendritica Pers., Skvortzovia furfurella (Bres.) Bononi & Hjortst. The majority of the logs in this type of forest yielded Scytinostroma basidiocarps. Cladoderris and Scytinostroma formed basidiocarps over the entire log. Logs with Hypochnicium punctulatum (Cke.) Erikss., H. Sphaerosporum (Hohn. & Litsch.) Erikss., Scytinostroma aff. galactinum (Fr.) Donk, Scytinostroma sp1, Scytinostroma sp2, Skvortzovia furfurella (Bres.) Bononi & Hjortst., Trechispora cohaereuns (Schw.) Julich. & Stalp., and Trechispora sp had apparently a higher rate of decay than others. Antrodiella hydrophila (Berk. & Curt.) Ryv., Hypochnicium sphaerosporum (Hohn. & Litch.) Erikss., Hymenochaete aff. dura (Berk. & Curt.), Lentinus calyx (Speg.) Pegler, Pachykytospora alabamae (Berg. & Cke.) Ryv., Porodisculus pendulus (Schw.) Murr., Schizopora flavipora (Cke.) Ryv., Scytinostroma aff. galactinum (Fr.) Donk and Trechispora cohaereuns (Schw.) Julich & Stalp., are reported for the first time in Brazil.
M Aparecida de Jesus


Electronic noses for detection of rot in wood
1996 - IRG/WP 96-20098
In an ongoing project an electronic nose is being studied and developed for detection of volatile organic compounds (VOC) emitted from wood colonised and decayed by fungi. The electronic nose consists of an array of gas sensors with different selectivity patterns for different groups of volatile organic compounds (VOC). The use of pattern recognition routines implemented by artificial neural networks (ANN) is used to evaluate data from the sensor array. The responses from the sensor array have been correlated to weight loss of and contents of chitin in the decayed wood samples. The results obtained so far indicate that the electronic nose qualitatively can detect significant differences between sound and decayed sapwood of Scots pine (Pinus sylvestris). Preliminary results also indicate that the electronic nose can detect differences between decay types like brown rot (Lentinus lepideus) and soft rot (Phialophora A). Results from a study aiming at investigating the abilities of the electronic nose to quantitatively detect different stages of decay is now being analysed statistically. The influence on the responses from the sensor array due to variation in relative humidity, moisture content of the decayed wood samples and temperature have also been studied.
K Nilsson


Isolation of the dry rot fungus, Serpula lacrymans, from the forests of the Himalayan Foothills
1995 - IRG/WP 95-10129
Previous expeditions to the Himalayas (Singh 1993, 1994) have reported on the presence in this area of the dry rot fungus Serpula lacrymans. However, attempts to isolate the organism from material brought back from these expeditions were not successful. In this paper we report on the isolation of Serpula lacrymans from spores and cord material brought back from the Narkanda region of the Himalayas. Whilst morphological analysis suggested the nature of the material as being Serpula lacrymans confirmation of this has been via protein fingerprint studies using SDS-PAGE. In this paper the natural habitat of the dry rot fungus will be discussed and compared with the building environment in which the organism grows in Europe, Japan, etc. In addition information on a range of other assowiated fungal species, also isolated from the Himalayan forest, will be given.
N A White, J W Palfreyman, J Singh, S Singh


Artificial drying of impregnated wood
1987 - IRG/WP 3448
Sawn timber (Pinus Sylvestris) of dimension 50x150 mm was impregnated with CCA by a full-cell process. The timber was then dried in a conventional kiln or a special vacuum kiln where the timber was dried by circulating superheated steam. Drying time was 16 days and 2 days respectively. The aim of the investigation was to compare the physical appearence of the wood after drying by the two methods with particular reference to formation of checks. Moisture contents and checks were therefore recorded before and after drying. It was found that the number of checks formed was approximately the same by either drying system and no inner checks were found. The drying in superheated steam, however, caused bleeding of resin on the surface of the wood, which could be a disadvantage for some end uses.
M-L Edlund


Effects of artificial UV weathering and soft rot decay on heat treated wood
2005 - IRG/WP 05-40302
Oil and inert gas oven heat treated pine wood strips 100 µm thick were mildly heat treated (200°C, 30 mins linseed oil, 120 mins oven). Following treatment, specimens were exposed to UV weathering (300 hours) and decay by the soft rot fungus, Chaetomium globosum. The effects of each treatment were assessed by zero span tensile testing, microscopy and by FTIR. Tensile testing of heat treated strips showed greater strength losses in the oil treated samples (73%) than in the oven treated samples (26% loss). Heat treatment darkened the wood strips but this was photo-bleached on exposure to UV artificial weathering. The UV exposure caused some loss in tensile strength (35%) but the additional effects of UV on the tensile strength were less in heat treated wood (oil 15%, oven 18%). The combined effects of UV and fungi on the tensile strengths were less severe for treated wood than in untreated wood, (oil 4%, oven 18%) thus some protection was afforded by the heat tretaments. Exposure of untreated wood strips to the soft rot fungus caused some loss in tensile strength (32%), but heat treated wood showed small but not statistically significant gains in tensile strength after fungal exposure (oil, gain 30%, oven, gain 3%). Microscopic examination confirmed that a soft rot was minimal in heat treated samples, i.e. it was mainly confined to wood cell wall penetration. The combined effects of UV and fungi caused further losses of tensile strength in both oven and oil heat treated samples, but this loss was less severe than that which occurred in untreated controls. However, due to the severity of the initial losses caused by the oil heat treatment, the highest losses overall were in those oil heat treated samples exposed to UV (82%) and UV and decay (78%). Microscopic examination revealed that decay was more advanced in UV exposed samples. The FTIR spectra of oven heat treated samples did not show any change, while the oil heat treated samples increased absorbance at 1737cm-1 and 1450cm-1 relating to the presence of oil. Following fungal decay, no changes were observed, this corresponds with the cavity attack by soft rot fungi, which leave adjacent portions of cell wall material untouched. The ultra violet exposure affected the spectra of all specimens, increasing the absorbance at 1737cm-1. This relates to photo-degradation of the hemicelluloses, forming new carbonyl groups. In the UV exposed untreated wood there were also increases in absorbance at 1510 and 1160cm-1 relating to alterations in lignin structure.
M D C Hale, S C Ghosh, M J Spear


A summary of work carried out to compare natural and artificial weathering for preconditioning test specimens in testing anti-stain chemicals for wood in service
1976 - IRG/WP 266
Since 1972 work has been in progress within CEN to establish a European standard for the testing of wood preservatives designed to prevent blue-staining of wood in service. The method is based on the Butin test and involves pre-weathering of the samples prior to biological testing. The weathering regime employed is 6 months outside exposure from March to October. This imposes severe limitations on the number of tests that can be carried out each year and has prompted considerable interest in an artificial weathering procedure which can be used instead of natural weathering. Recently four European laboratories (EMPA, BAM, IC, PRL) have been involved in assessing artificial systems (Xenotest, Marr, Gardener wheel, weathering tunnel) and this report has been prepared at the request of CEN in order to assess the accumulated data and make recommendations back to the CEN. This document presents only a brief account of the work and fuller details can be obtained directly from the laboratories concerned.
D J Dickinson, A F Bravery


List of wood-destroying fungi in Iran
1976 - IRG/WP 138
This list gives information on the wood-destroying fungi collected in the Iranian forests and from felled logs and boards in sawmills until now. They are mainly from the region of the Caspian Forests and from the climatically dry region between Teheran and Azarbaidjan, North Iran. It is understood, that this document may help to give more knowledge outside the country about the specific problems of Iran, or concerned with the regions of the Middle East with great varieties of climate. The collection, which is far from complete, includes 76 species of fungi belonging to 46 different genera. Several of the species have been published already nationally, some internationally. Some species have just been recognised recently in Iran and are mentioned for the first time. These species are marked with (+). All samples of fungi collected are conserved and kept in the laboratories of the Department of Wood Science at the Faculty of Natural Resources, Karadj. Their identification was undertaken by the author and with help of the Centre Technique du Bois, Services des Recherches et Essais (Lab Mycologie du Bois), Paris, and of the Royal Botanic Gardens, Kew.
P Soleimani


Xenon simulation of natural weathering of external joinery preserving - Finishing systems
1992 - IRG/WP 92-2412
Semitransparent wood stains ('lazures') for external joinery have developed by means of product combination towards complete wood finishing systems that are easy to applicate, have a good weathering resistance and low maintenance cost. The search for enhanced formulations and the possibilities to standardize these products or treatment systems are always facing long periods of weathering tests. Extensive research was conducted to compare natural weathering with artificial ageing, using a scheme based on two cycle units commonly used for artificial weathering and intermediate low temperature exposures. Statistical analysis of test results showed good similarity between both natural weathering and Xenon ageing
J Van Acker, M Stevens, M Nys


Durability of plywood made from soft- and hardwoods assessed according to ENV 12038 after artificial and natural ageing
2000 - IRG/WP 00-20191
Plywood was prepared from Norway Spruce and pure heartwood of Douglas Fir, Scots Pine, European Oak, False Acacia and Macoré using a phenol-formaldehyde glue. The panels of 38 mm in thickness were pre-conditioned according to the following procedures: a) 12 weeks storage at 20°C/65% rh, b) 2 weeks artificial weathering (with rain and UV-radiation at changing temperatures), and c) a natural weathering according to ENV 12037 for 3 month, 6 month and for 9 month whereby the ENV 12038 specimens were cut from the lap-joints. In general for softwood panels the decay was lowest after a 12 weeks` storage and the artificial weathering increased the decay rate more than the natural weathering applied. For False Acacia the durability was gained as predicted by EN 350-2 but not for the other species. Especially for European Oak and Macoré the durability was much lower than expected. Further, it has to be mentioned that the specimens usually showed a more intensive attack close to the nutrient media than at the top of the specimens. This indicates that the laboratory results might be influenced by the thickness of the panel tested because thinner material would be more equally degraded and thus would show a lower grade of durability.
H Leithoff, R-D Peek


Resolution from IRG Working Group II Sub-group 4 'Stain in timber in service'
1984 - IRG/WP 2230
Sub-group 4 of IRG Working Group II has completed a series of studies of artificial weathering as an alternative to natural weathering in relation to testing the efficacy of chemicals in preventing blue stain in service. The Sub-group reports that within the limits of the equipments studied and described in its report Document No: IRG/WP/2215 the extent of blue stain varied little as a direct consequence of varying the artificial weathering system. The Sub-group considers that any or all of the methods based on the Atlas, Marr or Xenotest systems (as described in Table 4 of Document No: IRG/WP/2215) are suitable on technical grounds for inclusion in a specified methodology.
D J Dickinson


Effectiveness of copper/chromium salts as wood preservatives against Limnoria tripunctata Menzies in laboratory tests
1977 - IRG/WP 431
During the last joint meeting of IRG and COIPM a co-operative programme of tests with copper/chromium salts as wood preservatives against marine borers was discussed and agreed. In this connection the results of a laboratory test in the BAM with Limnoria tripunctata Menzies will be of interest. But as the respective paper is written in German (H. Kühne; G. Becker: Laboratoriumsversuche über die Wirkung kupferhaltiger Schutzsalzgemische auf die Holzbohrassel Limnoria tripunctata Menzies) (Material u. Organismen 5 (1970) No 4, 307-319) a comprehensive summary is given in English for IRG-COIPM members.
H Kühne


Laboratory tests on light organic solvent preservatives for use in Australia. - Part 6: Soft rot resistance of three fully formulated preservatives on different timber substrates
2000 - IRG/WP 00-30245
The above-ground soft rot resistance of substrates treated with three fully formulated light organic solvent preservatives (Cuprivac Green WR, Impresol WR 205 and Vacsol) was studied using a modified vermiculite burial method. The substrates were sapwood of Pinus elliottii and P. radiata and heartwood of Eucalyptus regnans, Pseudotsuga menziesii, Shorea sp. (a lower and a higher density source) and Thuja plicata. Following artificial weathering, replicate test blocks were exposed to either Chaetomium globosum or Lecythophora mutabilis. C. globosum caused 3% or more mass loss of the water and solvent (white spirit) impregnated controls of all three hardwoods and two of the four softwoods, whereas L. mutabilis caused similar attack in only E. regnans and P. radiata. The P. menziesii and T. plicata heartwoods were naturally durable to both soft rot fungi and, hence, no further conclusions can be drawn. None of the preservatives, at the highest retention tested, protected E. regnans from attack by C. globosum, whereas the highest retentions of both the Cuprivac Green WR and Impresol WR 205 protected all other timbers from this fungus. At the highest retention, the latter preservative was the only one to protect E. regnans from L. mutabilis.
G C Johnson, M A Tighe, J D Thornton


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