IRG Documents Database and Compendium


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Studies on the biological improvement of permeability in New Zealand grown Douglas fir
1983 - IRG/WP 3231
This report outlines progress towards optimizing conditions for water storage of New Zealand grown Douglas fir with the aim of improving permeability to water-borne preservatives, in particular CCA. Small scale laboratory tests are in progress but the need to scale up to potential commercial applications is being considered. Mixed populations of bacteria isolated from 10 week water sprinkled Dougl...
K J Archer


Successive collections of Basidiospores from wood decay fungi (in vitro) show variation in germination levels on common media
1978 - IRG/WP 191
In the course of various preliminary experiments in which spore germination levels of 6 decay fungi on malt and water agar were recorded as controls, it was noted that one could not reliably obtain an expected level of spore germination for any particular fungus. Inconsistent 'control' spore germination levels of a fungus greatly complicates large scale experiments in which compa...
E L Schmidt, D W French


Microscopical analysis of formaldehyde-acid modified wood
1981 - IRG/WP 3182
Cross-linking of wood with gaseous formaldehyde improves its hygroscopic and dimensional behaviour, and its resistance against micro-organisms. However, formaldehyde cross-linking reactions take place only in the presence of an acid catalyst, which results in losses in mechanical By optimization of a formaldehyde-sulfur dioxide vapour phase process the reaction conditions were established to limit...
M Stevens, N Parameswaran


Fungal Stain Development in Canadian Hardwood Logs
2004 - IRG/WP 04-10505
In most sawmills around the world, trees are harvested into logs and stored in the forest or in a log yard for a period of time before being sawn into lumber. These logs may be attacked by various pigmented fungi, which results in staining of the wood. Since hardwood species are used to a great extent in furniture manufacturing and in the making of other valuable wood products, the reduction of wo...
Dian-Qing Yang, M-C Bisson


Ability of chitosans to limit wood decay under laboratory conditions.
2004 - IRG/WP 04-30339
Chitosans have recently been explored for controlling a number of plant pathogenic fungi and have shown some promise for controlling stain fungi on wood. The potential for using chitosans either alone or in combination with copper sulfate to protect wood from fungal decay was explored using maple veneers. Chitosan treatment reduce weight losses caused by two brown rot and one white rot fungi, howe...
M Maoz, J J Morrell


Risk of pulmonary damage as a result of an evaporation of ca. 50 ppb = 42 mg HF, evaporated from wood treated by difluorides
1987 - IRG/WP 3401
In this review of the literature the effects of fluorides and fluorine on man are described, especially the low level effects of inhaled HF on human beings. The term "fluoride" is used as a general term everywhere, where exact differentiation between ionic and moluecular forms or between gaseous and particulate forms is uncertain or unnecessary. The term covers all combined forms of the element, r...
H F M Nijman


Association of contents of nitrogen and sugars in rubberwood (Hevea brasiliensis) clones with susceptibility to sapstain by Botryodiplodia theobromae, Aureobasidium pullulans and Aspergillus niger
1999 - IRG/WP 99-10307
The purpose of this study was to determine if nitrogen and sugar contents in rubberwood from three selected varieties (clones) rubber trees would affect the rate of colonisation by Botryodiplodia theobromae (a tropical sapstain fungus), Aureobasidium pullulans (a temperate sapstain fungus) and Aspergillus niger (a common mould fungus). Sapstain growth was rated daily until at least 50% mycelial co...
A J Ashari, J W Palfreyman, A H H Wong


Do CCA treated support stakes cause increased arsenic level in crops?
2003 - IRG/WP 03-50204
Trial of using CCA-C treated eucalypts stakes for supporting banana plants in Guangdong Province, China, began in 1998 and later it was expanded as a demonstration program of a joint International Tropical Timber Organization–Chinese Government timber preservation project in 2000. The greatest concern was whether the crop would be contaminated by the preservatives, arsenic in particular. Data fr...
Li Zhaobang, Su Haitao, Liang Linqing


Analysis of volatile organic compounds (VOC's) from Trichoderma spp.: effect of media composition on VOC production and level of inhibition of wood decay fungi
1997 - IRG/WP 97-10207
Production of volatile organic compounds (VOC's) by two Trichoderma isolates grown on either malt extract or minimal media was examined and statistically assessed to identify which VOC's were predominantly produced on each of the two media types. The VOC's were captured onto chromatographic absorbent from above the cultures of the fungi before being analysed by integrate...
A Bruce, R E Wheatley, C Hackett, A Kundzewicz


The effect of added nutrients on growth rate and decay capacity of Serpula lacrymans
1990 - IRG/WP 1427
At the previous meeting a new technique was presented that enables both fungal growth rate and wood decay rate to be measured using the same timber specimen. The technique (IRG/WP/1384) has previously been carried out with 1% malt as the sole nutrient within the small jar that provides the inoculum for this method. Results presented here relate to an additional level of 5% malt, with or without a ...
J D Thornton, A McConalogue


A case for ecosystem-level experimentation - A discussion paper
1986 - IRG/WP 1296
Although laboratory bioassays provide a first step in testing for potential termiticides and assist in formulating recommendations of these chemicals for regulatory agencies and users, they are not designed for predicting effects on natural populations (including humans) and on ecosystem-level features. To overcome this we need microcosm studies, carefully controlled experimental manipulations of ...
J R J French


Fungal decay resistance of Rubber wood treated with heartwood extract of Rosewood
2005 - IRG/WP 05-30367
Alcoholic extract of Dalbergia latifolia heartwood was studied for its toxicity towards wood decaying fungi. Rubber wood blocks were treated with this extract to three different retention levels (0.1%, 0.2% & 0.5%) and the treated wood blocks were assessed for their resistance towards two white rot and two brown rot fungi. Treated blocks showed improved resistance over the control blocks. At 0...
A K Sethy, H C Nagaveni, S Mohan, K T Chandrashekar


After 18 years, preservative dipping and brush treating continue to provide protection to shingles of western wood species
1997 - IRG/WP 97-30156
The presence of residual preservation in dip-treated and brush-treated shingles of various species from the western United States was assessed 18 years after installation using Aspergillus bioassays. The performance of western redcedar (Thuja plicata) was compared to western hemlock (Tsuga heterophylla), sugar pine (Pinus lambertiana) and western larch (Larix occidentalis). Untreated shingles of a...
T C Scheffer, D J Miller, J J Morrell


The influence of fungal species and the level of decay on the mortality and feeding activity of adult Euophryum confine (Broun)
2002 - IRG/WP 02-10448
The mortality and feeding activity of adult Euophryum confine (Broun) (Coleoptera: Curculionidae) are used to establish the substrate conditions most suitable for their rearing. Weevils were allowed to feed on Pinus nigra (Arnold) sapwood blocks, either undecayed or decayed to 10% weight loss ±5% by two brown rots Coniophora puteana (Schum.:Fr.) Karst. and Serpula lacrymans (Wulf.:Fr.) Schroeter...
M Green, A J Pitman


A determination of the toxic level of ACQ2100 wood preservative for the powder post borer Lyctus brunneus (Stephens)
1994 - IRG/WP 94-20029
The sapwood of two Lyctus susceptible Australian hardwoods, messmate (Eucalyptus obliqua L'Herit.) and black bean (Castanospermum australe A. Cunn. et Fraser ex Hook) were pressure impregnated with ACQ2100, a wood preservative, to produce replicates of a range of retentions. Preservative retentions were determined by solution weight uptake at treatment and chemical analyses of selected sa...
A R Moffat


Inducing and Stimulating Spalting in Sugar Maple
2008 - IRG/WP 08-10652
Spalted wood has gained popularity in recent years as consumer preference has shifted towards unique and custom products. The process by which spalting is induced in clear lumber has evolved over time, and now involves much more than beer drinking and outdoor burial. Our work on the process of reliably producing spalted wood began in 2004 and involved testing a wide variety of white rot fungi on...
S C Robinson, D L Richter, P E Laks


The effects of acetylation level on the growth of Postia placenta
2011 - IRG/WP 11-10751
To understand the defence mechanisms utilized by decay fungi when exposed to different wood protection systems the study of gene expression can give us some answers. When the DNA sequences are known, primers can be designed to detect transcripts of genes with gene products related to basic cellular processes and hyphal growth. The characteristic gene products induced in different fungi by differen...
A Pilgård, G Alfredsen, C G Fossdal, C J Long II


Design, synthesis, characterisation and effectiveness of ‘Locked-in-Boron’ chemicals for H3.2 level of wood protection
2011 - IRG/WP 11-30577
Boratrane molecules with five-membered and six-membered molecular ring systems, and with various ring substituents were synthesised, characterised and formulated for wood treatment for accelerated laboratory bioassays using wood decay fungi as test organisms. Six-membered ring boratranes showed lower efficacy in laboratory assays than five-membered ring boratranes. One alkyl-substituted boratran...
R Franich, H Kroese, S Gallagher, S Hill, B Kelly, G Billett, R Meder, W Rae


The effects of acetylation level on the growth of Postia placenta over 36 weeks
2012 - IRG/WP 12-40589
Genomic sequencing gives us a tool to systematically and rapidly discover novel genes, how their products function in the cell, and explore their interactions. When the DNA sequences are known, primers can be designed to detect transcripts of genes with gene products related to basic cellular processes and hyphal growth. The characteristic gene products induced in different fungi by different wood...
A Pilgård, G Alfredsen, C G Fossdal, C J Long II


Method for determining the critical moisture level for mould growth on building materials
2013 - IRG/WP 13-20530
The natural conditions of relative humidity (RH) and temperature (T) in different parts of a building is rarely constant over time. Instead, RH and T often vary cyclically and may pose a risk of mould growth as these conditions are the two key environmental parameters that controls mould growth. Consideration to both humidity and temperature conditions and the susceptibility to mould in a material...
A Ekstrand-Tobin, P Johansson, G Bok


Critical moisture levels and mould resistance of five different wood treatments
2013 - IRG/WP 13-30632
Mould resistance of five different treatments were tested using two methods, a recently developed method for the determination of critical moisture levels of building materials (RHcrit), and ASTM D3273-94. The critical moisture level method exposed samples at 22 °C and 98, 92, 86 and 82% relative humidity (RH) for 12 weeks. ASTM D3273-94 was performed at 29 °C and about 95% RH. Treatments c...
G Bok, P Johansson, A Ekstrand Tobin, S Bardage


The impact of pre-drying on treatment level variations of esterified solid wood analysed by X-ray densitometry
2023 - IRG/WP 23-40977
Wood modification requires homogenous treatment levels within the wood matrix to prevent insufficiently treated areas being subject to biodeterioration. Esterification of wood by citric acid and sorbitol can show differences in density caused by uneven chemical distribution during the curing phase and can be detected by x-ray densitometry. This study used density profiling to investigate the influ...
A Treu, S O Amiandamhem, E Larnoy