Your search resulted in 323 documents. Displaying 25 entries per page.
Kiln drying of poles as a means of solving the problems of pre-treatment decay in poles
1985 - IRG/WP 1263
The concept that pre-treatment decay can cause wide variation in the treatability of wood and especially wood poles has caused much discussion and debate in wood preservation circles. Yet it seem only logical that if decay has effected the strength characteristics of the wood and caused a differential moisture content in the wood the treatment of the end product will be highly variable and the lon...
J A Taylor
Studies on the permeability of Norway spruce (Picea abies)
1987 - IRG/WP 2295
It is well known that the bordered pits play a dominating role for liquid transport in softwoods. The mechanism behind pit aspiration during drying or heartwood formation seems to be well understood. The reason why the fixation of the membrane (torus) to the pit opening remains almost irreversible is, however, still unclear. A technique has been developed combining so-called "solvent exchange dryi...
I Johansson, K Nordman-Edberg
The effect of preservative distribution in small blocks of Pinus sylvestris on the toxicity of tributyltin oxide to Reticulitermes santonensis Feytaud
1971 - IRG/WP 206
Small blocks of Pinus sylvestris (50x25x15 mm³) were treated by a full-cell method with various concentrations of tributyltin oxide in benzene. Replicate blocks were then freeze dried, rapidly air dried or slowly air dried and exposed to surface attack by the subterranean moistwood termite Reticulitermes santonensis Feytaud. At all concentrations it was found that the freeze-dried blocks were mor...
M P Levi, D N R Smith
The biological effectiveness of wood modified with heptadecenylsuccinic anhydride against two brown rot fungi: Coniophora puteana and Gloeophyllum trabeum
1992 - IRG/WP 92-3705
A modified soil block test was carried out using wood samples reacted with heptadecenylsuccinic anhydride (ASA). This modification gave good resistance to decay brought about by the brown rot fungi Coniophora puteana and Gloeophyllum trabeum during the twelve week exposure period. Results indicated that there was a good correlation between increased loading of modifying reagent and an increase in ...
C Codd, W B Banks, J A Cornfield, G R Williams
Heat transfer and wood moisture effects in moderate temperature fixation of CCA treated wood
1994 - IRG/WP 94-40022
Practical aspects of heat transfer and fixation of wood exposed to drying conditions after CCA treatment are considered. The rates of heat transfer and CCA fixation are substantially influenced by the cooling effect of water evaporating from the wood surface when drying occurs during fixation. At least in the early stages of fixation, the wood temperature approaches the wet bulb temperature, rathe...
J Chen, M Kaldas, Y T Ung, P A Cooper
Computer-assisted ranking of potential biocontrol fungi based on data from laboratory screening trials
1993 - IRG/WP 93-10023
Forty two fungal isolates were screened for antibiotic activity. In these sceering tests inhibition of target wood decay fungi was expressed as a series of numerical scores for each isolate. These scores, along with values for 5 other charactetistics, were used to assess the isolates. Using selection indices, isolates were judged on the basis of all the characteristics combined and, ranked in orde...
M W Schoeman, D J Dickinson
Laboratory studies on control of sapstain and mold on unseasoned wood by bacteria
1991 - IRG/WP 1493
A malt-agar and nonagar laboratory test was used to evaluate the efficacy of bacterial preparations as biological control agents against several sapwood-inhabiting fungi. Both nonsterilized and filter sterilized bacteria preparations prevented attack by the sapwood-inhabiting fungi. Streptomyces rimosus was the most effective bacteria, giving good protection, with a 1-hr soak in a filter-sterilize...
T L Highley, R Benko, S C Croan
Siderophore production by Trichoderma spp. and its importance in the biological control of wood decay fungi
1994 - IRG/WP 94-10070
Competition for iron as well as other micro-nutrients is an essential component of the microbial ecology of many ecosystems. A wide range of micro-organisms including fungi and bacteria have been shown to increase their ability to efficiently capture iron through the production of specialised iron chelating compounds called siderophores. Since iron is in low supply in wood and has been implicated ...
U Srinivasan, A Bruce, T L Highley
Biological control of decay
1975 - IRG/WP 135
One approach to the biological control of decay in standing poles, live trees or seedlings is with microbial immunising commensals or IC.·These are microorganisms able to grow in the wood without damaging it and as a result of such growth to protect against certain types of decay. Scytalidium and Trichoderma spp have been tested in the field. The latter species have shown an establishment rate in...
J Ricard
Alternatives to preliminary oven-drying prior to spot-testing treated timber for borate or TBTN preservative penetration
1995 - IRG/WP 95-20067
Commonly-used penetration test procedures for timber treated with borate or organotin wood preservatives demand preliminary oven-drying before application of the spot-testing reagent(s), in order to achieve reliable results. The delay of 12 hours or more during oven drying is often a nuisance. Modifications to the spot-testing procedures, involving alternative solvents and acidification conditions...
M J Kennedy, A Zosars, J Norton
Effect of Volatiles from Trichoderma species on the regulation of protein synthesis in Serpula lacrymans isolates
2002 - IRG/WP 02-10440
The growth of wood decay fungi has previously been shown to be inhibited by volatile organic compounds (VOCs) from selected Trichoderma isolates. No mechanism of action has however been established for such inhibition. This paper reports the effects of VOCs produced by Trichoderma pseudokoningii, T. viride and T. aureoviride on the growth of four dry rot isolates and corresponding protein synthesi...
S Humphris, R Wheatley, E Buultjens, A Bruce
Resistance of acetylated wood to biological degradation. Evaluation of field test
1997 - IRG/WP 97-30139
Acetylated wood samples were tested in ground contact (stake test) at two test fields, one in Simlångsdalen, Sweden, and one in Viikki, Finland, according to European standard EN 252. The test samples were inspected annually and their condition was compared with that of untreated controls and of samples treated with two reference CCA preservatives. The use of untreated controls and preservative t...
P Larsson Brelid, R Simonson, Ö Bergman
Effect of nutrient regimes, temperature, pH, and wood sterilization method on performance of selected bioprotectants against wood staining fungi
1992 - IRG/WP 92-1551
The effect of nutrient regimes, incubation temperature, media pH, and wood sterilization method on performance of four potential bioprotectants (Pseudomonas putida, Pseudomonas cepacia, Bacillus subtilis, and Trichoderma harzianum) against wood staining fungi were evaluated using small ponderosa pine samples over a four week period. Incubation at 32°C resulted in slight increases in the degree of...
J J Morrell, C M Secton
Wood kiln drying. Simple process of material treament or soft method of preservation? (Le séchage arificiel du bois. Simple opération de traitement du metériau ou méthode douce de préservation?)
1993 - IRG/WP 93-50001-14
Among the processes enabling to extend wood durability, kiln drying can be considered as a treatment and soft preservation method. Dry woods are naturally durable provided they are not subject to important retaking of the moisture. Drying thanks to the application of temperatures from 50 to120°C enable to execute a thermic treatment which kills grubs and mushrooms to ensure a sterilization that c...
F More-Chevalier
Adequate preservative treatment of kiln dried Eucalyptus camaldulensis and Acacia mangium for tropical and subtropical wood poles
1996 - IRG/WP 96-40075
The Eucalyptus camaldulensis and Acacia mangium round timbers kiln-dried at EMC and full cell pressure treated with CCA-C ensured requisite penetration and adequate dry retention (30 kg/m³ or 4% w/w). The sufficient inherent strength, seasoning property, treatability of sapwood and heartwood equivalent to 44% of radius, natural durability of heartwood, and field investigation on service performan...
A K Lahiry
Preliminary evaluations of a small wafer assay for screening potential biological control agents
1989 - IRG/WP 2332
Screening potential biological agents for controlling wood decay fungi poses a dilemma. The ideal test would eliminate as many variables as possible. Most tests utilize pure cultures of the test organism on an artificial media which in no way resembles wood. The use of sawdust improves this approach, but the sawdust increases fungal access to the lignocellulose matrix, potentially inflating the im...
C M Freitag, J J Morrell
An observation of seasoning, preservative treatment and storing of CCA treated 30 bangladeshi hardwood species for crossarms
1995 - IRG/WP 95-40058
Observed kiln seasoning, preservative pressure treatment and storing of CCA treated 30 Bangladeshi hardwood species for crossarms. It revealed that it was very difficult to kiln season and preservative pressure treatment of thirty species together in a single charge and found that when species of different specific gravity kiln season together there occur some objectionable seasoning degrades, and...
G N M Ilias, M D Rokib-ul-Hafiz
The Effect on Biological and Moisture Resistance of Epichlorohydrin Chemically Modified Wood
2002 - IRG/WP 02-40224
Southern pine solid wood and fiber were chemically modified with epichlorohydrin to help in understanding the role of moisture in the mechanism of biological effectiveness of chemically modified wood. The solid wood had weight gains from 11% to 34%, while the fiber had weight gains from 9% to 75%. After modification, part of the specimens were water leached
for 2 weeks or extracted for 2 hours ...
R E Ibach, B-G Lee
Improved preservative penetration of spruce after pre-treatment with selected fungi. II. Creosote treatment, analysis and strength testing
1998 - IRG/WP 98-40106
This paper describes the creosote treatment and analysis of logs pre-treated with selected fungal agents as a method of increasing the porosity of the wood prior to preservative treatment. The paper also reports the subsequent strength testing of the timber to evaluate the effects of the fungal pre-treatment on the structural integrity of the wood.
European spruce logs were pre-treated with eithe...
E J Tucker, A Bruce, H J Staines, B Rosner, K Messner
The influence of drying and chemical stress on the lignin degradation in aspen by Phanerochaete chrysosporium
1992 - IRG/WP 92-1573
Wood wafers of Populus tremuloides sapwood were incubated on common media with the white rot fungus Phanaerochaete chrysosporium (wild isolate) and subjected to cyclic drying or chemical agents (low levels of borate or trifluoperazine [a calmodulin antagonist]). After a mass loss of approximately 5.5%, wafers were dried and analyzed for acid-insoluble lignin. Those wafers containing chemical agent...
E L Schmidt, Y-L Lin
Biological control of wood decay
1992 - IRG/WP 92-1531
This paper provides a general discussion of the principles underlying the concept of using biological control agents for the protection of wooden materials from decay. The rationale for the current upsurge in interest in biological control is discussed and a critical appraisal of the technology compared with the use of chemical wood preservatives is included. The advantages and limitations associa...
A Bruce
Biological Safety Evaluation of Animal Contact of Preservative-Treated Wood
2003 - IRG/WP 03-50196
Biological safety of preservative-treated woods that could be contacted to human and animal was evaluated for rat and rabbit exposed to CCA-, ACQ- and CCFZ-treated woods. The accumulation of preservatives ingredient in the rat’s plasma and viscera, and the transforming function of replacing preservatives were examined in this study. The result indicated that preservative-treated wood did not bri...
Dong-heub Lee, Dong-won Son, Myung Jae Lee, Chang Ho Kang, Cheon Ho Kim, Eui-Bai Jeung
Improved preservative penetration of spruce after pre-treatment with selected fungi. I. Fungal pre-treatment of pole sections
1998 - IRG/WP 98-40117
European spruce logs were pre-treated with either Phanaerochete chrysosporium, Dichomitus squalens, Trichoderma viride and Trichoderma aureoviride for incubation periods of between 1-4 weeks prior to pressure treatment with creosote in a commercial treatment plant and analysed for strength and creosote uptake (see part II Tucker et al.). A method to pre-treat logs was optimised. The pole sections ...
B Rosner, K Messner, E J B Tucker, A Bruce
Investigation of extracellular mucilaginous material in some wood decay fungi
1996 - IRG/WP 96-10188
The external morphology of the extracellular mucilagenous material (ECM) produced by Coriolus versicolor and Coniophora puteana during colonization of Scots pine and beech was studies using SEM. Specimens were examined in the frozen hydrated, freeze-dried and critical point dried state. All technics produced artefacts but the ECM was best preserved when examined the frozen hydated state. Critical ...
A R Abu, D J Dickinson, R J Murphy
Antagonistic effect of Trichoderma spp. against basidiospores
1993 - IRG/WP 93-10027
All screening of potential biocontrol agents of wood decay fungi have previously been used against basidiomycete mycelium. Similarly, experiments designed to evaluate the mechanisms involved in antagonism (soluble metabolites and volatile antibiotics) between biological control agents and target fungi have always been carried out on mycelial inoculum. Basidiospores are a primary source of infectio...
U Srinivasan, T L Highley, S C Croan, A Bruce