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Fungi causing sap stain in wood
1980 - IRG/WP 199
The present paper is a revised edition of former Document No: IRG/WP/125. It contains some additions and an explanation of terminology, as was suggested at a previous meeting of the Group. The paper is a compilation based mainly on available literature. Some of my own unpublished results have been added together with other unpublished data which have been received from the Bundesanstalt für Materialprüfung in Berlin and from colleagues at the Department of Forest Products, Swedish University of Agricultural Sciences, which are acknowledged with thanks. Fungi, described in the text, have been selected according to the following principles: a) the most common and important blue stain fungi, b) less common fungi which have been found in several countries or on several host trees, c) fungi which seem to be of minor interest as blue stain fungi, but which have been used recently in experimental work considering their physiological characters, susceptibility for toxic substances etc. The author regrets that this paper does not cover the tropical fungi, as there have been only a few notes about these in reviews and as the original papers have not been available to our library.
A Käärik

Monographic cards for wood-destroying fungi. [Fiches monographiques pour les champignons lignivores]
1970 - IRG/WP I 5B
C Jacquiot

Modélisation sur maquette du rejet accidentel d'un gaz toxique et inflammable dans l'atmosphere - Emission de type "bouffée d'oxyde d'éthyléne [Water model simulation of toxic and flammable gases in the environment on industrial sites - Puff of ethylen oxide]
1990 - IRG/WP 3576
M Milhe

The dry rot fungus and other fungi in houses. Part 2
1993 - IRG/WP 93-10001
J Bech-Andersen

Scientific development for prolonging the service life of timbers by impregnating with creosote or organic solvent type preservatives in which additive has been incorporated
1977 - IRG/WP 382
Chemically impregnated wood has played a prominent part in the Telephone and Electricity Distribution Industry during the past century and there is no doubt that it will play an equally prominent part in the future. The reasons why wood poles and wooden, structures predominate, are that when adequately chemically impregnated with a recognised timber preservative to ensure the expected service life for the purpose envisaged, the timber is then fully protected against the ravages of wood destructive organisms. Furthermore, wood is endowed with many natural characteristics that make it a favourite pole and structural material. Its high strength, light weight, ability to absorb impact or shock from loads suddenly applied and ability to resist overloading for brief periods plus its well-known insulating qualities - all are important basic reasons for its predominance in pole line structure. The use of chemically impregnated timber often makes it possible to carry out a given construction programme at less cost, or to erect more structures for a given sum of money, than when more expensive construction materials are employed.
P R B D De Bruin

Long-term performance of a "wax" type additive for use with water-borne pressure preservative treatments
2000 - IRG/WP 00-40159
Field performance results are updated for matched CCA treated decking boards with and without an emulsion water repellent additive incorporated with the initial pressure treatment. Decks have been exposured for over 9 years in Harrisburg, NC. Boards were evaluated for in-service and laboratory performance for water repellent efficacy, as well as additive loadings in the boards after this exposure. All results support that these additives can provide long-term protection against many of the physical defects that develop in pressure treated wood during exposure.
A R Zahora

Biocides - Efficacy assessment and doses for wood preservatives (product type 8). Local/geographical aspects. Termite control as case study
1999 - IRG/WP 99-20181
Currently, the efficacy of a wood preservative, as biocidal product type 8, is assessed as a ‚critical value' (CV), an efficient dose (retention in wood at a given depth of penetration). CVs are planned to be adapted for exposure to basic target organisms (5 hazard classes) and additional requirements concerning the occurrence of local target organisms in relation with climate, building design and relevant economical impact. Among them, the termite case study is illustrative. The vote of a french law, on 26 may 1999, aiming to protect consumers and to organize termite control puts termites, a "local target at the euro scale and a universal one in some euro territories", in the spotlights of actuality and helps to point out some of the remaining questions raised by the implementation of Dir 98/8 on Biocides. Based on CEN/TC/38 simulated use tests, which doses have to be used for conditions of exposure and climate, ranging from polar to tropical? Practical proposals are made to take into accound local prescription based on actual target organisms, and move on to standard biocide profiles.
G Ozanne

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
T Nilsson

Proposals for collaborative work on laboratory soft rot testing
1986 - IRG/WP 2265
Proposals for collaborative experiments based on soil burial are presented. It is intended to study the use of defined horticultural loams with a view to obtaining more reproducability in laboratory soft rot tests.
D J Dickinson, S M Gray

Weather testing of timber - discoloration
2001 - IRG/WP 01-20221
The brightness and color saturation of the timber were reduced over time. The perception of an increasingly dark color in the timber over time is due to the gradual reduction in brightness. The period from May to September was characterized by the greatest discoloration of all three periods of the year. Because this period has the largest number of sunlight hours, and the timber is subjected to a greater amount of sunlight. Furthermore, the period from May to September coincides with the rainy season in Japan, which adds to the discoloration.
T Toyoda, M Azuma, Y Hikita

Literature survey on the permanence and distribution of salt-type wood preservatives
1969 - IRG/WP III 1B
The objective of this survey is generally to review some of the more important published work dealing with the distribution and permanence of salt-type waterborne wood preservatives in treated timber. The survey is limited to the major chrome-containing formulations and the classification system proposed by Becker (1964) has been adopted throughout. CK - chromium, copper (copper, chrome); CKA - chromium, copper, arsenic (copper, chrome, arsenate); CKB - chromium, copper, boron (copper, chrome, boron); CFK - chromium, fluorine, copper (copper, chrome, fluorine); CFA - chromium, fluorine, arsenic (fluor, chrome, arsenate); CF - chromium, fluorine (fluor, chrome). The literature compilation covers the performance of these preservatives assessed from laboratory tests, field tests and practical experience; their application and distribution in the treated wood; and their influence on materials such as glues, paints or metals and the wood itself. It is not the purpose of this survey to draw conclusions regarding the relative merits of the various formulations, the choice of a formulation in a given situation depending upon many factors outside the terms of reference of this review, and not all of a technical nature. In general, there is insufficient directly comparable data for a definitive assessment and in the few comparisons available special factors frequently apply.

Thermotolerant mould growth in dehumidifier kilns in New Zealand
1996 - IRG/WP 96-10169
Growth of Aspergillus fumigatus and Paecilomyces variottii is common on wood dried in dehumidifier kilns that operate within a temperature range of 35-55°C. Aspergillus fumigatus causes an unacceptable blue / grey discolouration of the woods surface and prolonged exposure to spores during handling of mouldy wood can cause health problems amongst timber workers. A survey of dehumidifier kiln operators in New Zealand was carried out to ascertain the extent of the problem and investigate control options. Significant growth only occurred if initial wood moisture content was above 80%. Results suggested that this was because high relative humidity (98-100%), for periods in excess of 5 days, was a requirement for extensive and profuse growth to occur. Only 3 of the 26 antisapstain treatments tested using a 3 week laboratory trial gave control of Aspergillus fumigatus at 40°C. Fumigation with 4 ppm (mg/litre of air) of formaldehyde gas controlled growth of Aspergillus fumigatus for periods up to 5 days and a second fumigation was often needed for long drying cycles (> 12 days). It seems likely that growth of thermotolerant moulds became a problem when use of pentachlorophenate as an antisapstain treatment was phased out (1988-89). Laboratory trials showed that this was one of the few fungicides that controlled Aspergillus fumigatus.
R N Wakeling, J G Van der Waals

Comparison of the effect of different soil sources on the type and rate of decay of CCA-treated pine exposed in a soil-bed
1984 - IRG/WP 2213
The types of decay observed in CCA-treated pine posts in horticultural situations in New Zealand can be reproduced using a soil-bed exposure. Radiata pine stakelets, untreated or treated to 1.4, 2.7, or 5.4 kg/m³ with Tanalith NCA, were exposed to six different soil sources. The local nursery soil used for all standard laboratory tests was found to represent the greatest decay hazard to untreated pine. Poverty Bay horticultural soils were more hazardous than the local field test site soil to CCA-treated pine. Soil collected from adjacent to a 'decaying' post could decay treated wood faster than soil collected from around a 'sound' post. Brownrot, softrot, and bacterial degrade was observed. All failures of untreated pine and early failures of CCA-treated pine were caused by brownrot.
J A Drysdale

Resin bleed after light organic solvent preservative treatment - the effect of drying method and process type
1986 - IRG/WP 3378
The effects of drying method and treatment process type on resin bleed were investigated. High-temperature drying of resinous radiata pine (Pinus radiata D. Don) heartwood resulted in improved wood permeability, higher preservative uptake, and greater resin bleed when treated by the Rueping process. Resin bleed was reduced substantially when timber was treated by the Lowry process, and totally eliminated when Bethell-treated. The incorporation of 2% wax into the preservative formulation may control resin bleed after Rueping treatment.
P Vinden

Interaction mechanisms of F/Cr/As/B type preservative and wood
1981 - IRG/WP 3183
The paper reports results of investigations on the fixation of the components of a F/Cr/As/B preservative in wood and its lignin and cellulosic components.
N Ermush, I Andersone

Bacterial staining of samba (Triplochiton scleroxylon)
1988 - IRG/WP 1362
Red- and green-stained areas on Samba wood have been tested by IR, X-ray and Neutron Activation Multielement Analysis. No difference could be seen between stained and unstained areas. The red- and green-staining seem to be related to the bacteria Pseudomonas aeruginosa which were isolated from both red- and green-stained areas on the wood surfaces.
K Hansen

Chapter 2 - Introduction to world bamboo
2007 - IRG 07-10635-02
In this chapter the bamboo species of the whole world along with local name, bamboo type, flowering type, locality and uses have been presented in 20 different Tables.
A K Lahiry

Copper-resistant fungi on pressure impregnated wood in Denmark
1994 - IRG/WP 94-10078
The occurence of Amorphotheca resinae Parbery and its asexual stage Cladosporium resinae (Lindau) de Vries on CCA and CCB treated wood has previously been shown. In the autumn 1993 some other blue stain fungi were found on CCP and CCB treated pine timber, such as Ophiostoma minus (Hedgc.) H. and P. Sydow, Ophiostoma pilifera (Fr.) H. and P. Sydow and Ophiostona piceae (Munch) H. and P. Sydow. The absense of arsenic from newly impregnated wood may create improved growth potential for species not previously found on pressure impregnated timber, such as the above-mentioned.
J Bech-Andersen, S A Elborne

Soft rot decay of Eucalyptus maculata Hook. in different soils from Queensland, Australia
1980 - IRG/WP 1113
In the present work, different Queensland soils were chosen and their gross effects on the decay of treated and untreated Eucalyptus maculata examined. The soils were also amended with various levels of phosphate to study the response of the wood decay mycota to an increasing supply of this nutrient. Phosphate amendment was chosen because of the wide-scale use of superphosphate on Queensland soils and the importance of inorganic phosphate in the carbohydrate metabolism of microorganisms.
L E Leightley, I W Russell

Photo-discoloration and Degradation of Wood and its Stabilisation by Modification with Benzoyl Chloride
2004 - IRG/WP 04-40274
Photo degradation of Pinus roxburghii (chir pine) and Hevea brasiliensis (rubber wood) was studied under artificial accelerated weathering conditions in a Xenon test chamber. The irradiated samples were analyzed for color changes and chemical changes. Analysis of colour changes in wood surfaces by UV-Vis. irradiation was carried out using a colour measuring (CIELAB) system and chemical changes were monitored using FTIR and fluorescence spectroscopy. Irradiation modified physical and chemical characteristics of wood surfaces and resulted in rapid colour changes, reduction in lignin content and increased concentration of chromophoric groups on the wood surfaces. Colour changes were correlated with formation of carbonyl groups and lignin decay rate determined by FTIR measurements. Fluorescence emission spectra measured from un-weathered wood shows excitation wavelength dependence. Photo irradiation leads to a rapid reduction in the emission intensity, broadening of spectra and a significant red shift in the emission maximum. Photo stability of wood surfaces esterified with benzoyl chloride was also assessed. The modification was characterized and analyzed by fluorescence and FTIR spectroscopy and photo-stability of modified wood was assessed. Esterification of wood by benzoyl chloride suppressed the colour changes (photo-discoloration) and also reduced the lignin degradation and generation of carbonyl groups on irradiated wood surfaces. Results show esterification of wood with benzoyl chloride was effective at inhibiting photo-degradation of wood polymers.
K K Pandey

A comparative study of CCA type C and B treated poles in service
1993 - IRG/WP 93-50001-05
CCA K33 type B and C treated utility poles, 9 pieces of each treatment type, were analyzed for preservative retention after 11 years in use. Borings were taking 1 m above and 0.3 m below the ground line. Also total amount of copper, chromium and arsenic was determined in soil surrounding the poles. The solubility of these active components in soil was monitored by using different leaching procedures. Remarkable losses of Cu, Cr and As were found in both type of poles, particulary As from type B poles. Exact figures could not be given because of missing original preservation data. In comparison to the natural background high As and Cu contents were found in soil. CCA type B poles emitted As up to 760 mg/kg (oven dried soil) which is least 760 times higher than the natural background (0.4-1.0 mg/kg). The average value of As emitted by C type poles was 92 mg/kg. The amount of copper varied from 10 to 50 fold to the background but no essential differenceswere noticed among the two groups. Type C poles emitted more Cr but the average figures were lower than that with As and Cu. The solubility of As, Cu and Cr, as a very important factor, was investigated by preparing series of leaching tests. Only slight differences were found between EPA (US Environmental Protection Agency) and water leaching tests. In both leaching tests As was the most soluble element and 1.2-1.1 mg/l of As in the soil connected to B type poles was in soluble form. The figures were much lower with the case of C type poles and were 0.16-0.26 g/l respectively. Additional tests also proved that lower pH values decreased the solubilily of As. The effect was even stronger with adding ferrous sulphate. On the contrary increases pH resulted higher solubility.
A J Nurmi

The possible significance of the lignin content and lignin type on the performance of CCA-treated timber in ground contact
1988 - IRG/WP 1357
The lignin in wood samples of Alstonia scholaris, Octomeles sumatrana and a Simaruba species have been analysed. These timbers are characterised by a high lignin content and low syringyl:guaiacyl ratios. Decay tests with two soft rot fungi showed that the timbers were less susceptible than timbers with a low lignin content and higher syringyl:guaiacyl ratios. Numerous data for field performance of Alstonia and limited information on treated Octomeles and Simaruba suggest that timbers with a high lignin content and low syringyl:guaiacyl ratios will perform well in ground contact when treated with CCA.
T Nilsson, J R Obst, G F Daniel

A study of decay type variability in variously treated Fagus sylvatica and Pinus radiata field test stakes exposed at a vineyard for 30 - 45 months
1998 - IRG/WP 98-10271
Pinus radiata test stakes were treated with 10 kg/m3 of CCA plus 4 lower retentions in a geometric series of 1.5. Fagus sylvatica was treated with 15 kg/m3 and 2 lower retentions. Both timber species were also treated with equivalent retentions of various new generation preservatives (P. radiata was also treated with creosote). Whilst these stakes were exposed at 11 sites in New Zealand (NZ) and 2 in Queensland Australia, this paper reports only data from a single NZ site where preservative and timber species effects on decay type were particularly pronounced. Of particular interest was the finding that copper-azole and copper-quat. treated pine was less susceptible to soft rot attack but more susceptible to attack from tunnelling bacteria, compared to CCA treated wood. Beech was not attacked by tunnelling bacteria but was attacked by an unusual type of fungal cavitation/erosion. These, and other preservative and timber species effects on decay type are discussed.
R N Wakeling, A P Singh

A study of the decay type potential of seven soils
1992 - IRG/WP 92-1539
The aim of this experiment was to determine the significance of the fungal inoculum potential and physico-chemical properties of five field trial test site soils, a garden compost known to cause white rot in copper treated fence palings, and soil from a zone between 2 and 15 centimetres from a CCA treated post with brown rot, in causing differential decay type in Pinus radiata and Poplus deltoides sapwood blocks. Two blocks of each species were buried in non-sterile soil in jars with the upper transverse face level with the soil surface. A block of the same species was placed, with the transverse face upwards, on the top of each buried block. Six replicate jars per soil type were used. A second set of jars containing 90% sterile potting compost and 10% non-sterile soil, for each of the seven types, was set up as described above. Soil moisture content was adjusted to, and maintained at, 30% of the dry weight. Decay type and weight loss was determined for each block after twenty weeks incubation at 25°C. Considerable differences of decay type and weight loss edited between the 100% and 10% soil regimes, soil type, and timber species. These differences and their significance are discussed.
R N Wakeling

Soluble nutrient content in wood and its susceptibility to fungal discoloration and decay in above ground and ground tests
2000 - IRG/WP 00-10336
The objective of this comprehensive study was to reveal the impact of soluble nutrients in wood on its susceptibility to fungal discoloration and decay in various tests, which is important for the test methodology and standardisation. Seven tests were carried out including pure culture above and ground contact tests, above ground field test and laboratory ground contact tests. The samples containing soluble sugars and nitrogen were more susceptible to mould discoloration than those poor in nutrients. A laboratory test with the fungus Penicillium brevicompactum predicted well the moulding tendency of the samples in the consequent field test. The samples rich in nutrients showed an average of 16% of mass loss whereas samples poorer in nutrients were significantly less affected (8-9%) after 120 days of exposure in a soil rich in soft rot fungi. A pure culture test with the soft rot fungus Phialophora mutabilis confirmed the above -mentioned observation. Garden compost, rich in both soft rot fungi and bacteria, caused severe mass loss (40-48%) of the samples after 120 days of exposure, but no difference in the mass losses between the samples rich and those poor in nutrients was measured. The content of nutrients was neither related to the mass loss of samples in a soil rich in brown rot fungi, nor in a pure culture test with the brown rot fungus Postia placenta. The nutrient status of samples as well as the choice of test soil can lead to completely different results and, consequently, conclusions. The results are in favour of taking samples with approximately equal content of soluble nutrients to decrease the variability of test results, e.g., mass losses.
O M Caballero, N Terziev

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