Your search resulted in 637 documents. Displaying 25 entries per page.
Soft Rot Decay of Cengal (Neobalanocarpus heimii) Heartwood in Ground Contact in Relation to Extractive Microdistribution
2003 - IRG/WP 03-10501
The heartwood of cengal (Neobalanocarpus heimii, fam. Dipterocarpaceae) is naturally durable. A square-sawn utility pole specimen of cengal heartwood, after 30 years in ground contact, showed 10-15 mm surface decay all around the ground line position, accompanied with isolated surface termite attack at the decayed region. Light and transmission electron microscopy (TEM) of the decayed regions prov...
A P Singh, A H H Wong, Yoon Soo Kim, Seung-Gon Wi, Kwang Ho Lee
Decay resistance of densified ammonia-plasticized stems of oil palm (Elaeis guineensis)
1991 - IRG/WP 3673
When wafers of oil palm stems (Elaeis guineensis) were plasticized with 28% aqueous ammonia and immediately compressed mechanically, the treated material, gained 73% in basic density (average basic density, 0.695 g/cm³), and was highly resistant to decay by wood rot basidiomycetes. Compared with the control specimens (density, 0.403 g/cm³), resistance to decay of the densified specimens by Corio...
A H H Wong, M P Koh
The dry rot fungus (Serpula lacrymans) in nature and its history of introduction into buildings
1999 - IRG/WP 99-10300
For many years the True dry rot fungus (Serpula lacrymans (Wulf.: Fr.)Schroet.) has exclusively been found in buildings. That is why it is called the True dry rot fungus. The origin of the fungus has always been a mystery, but a wild ancestor must have occured. In the literature there is some information about finds of Serpula lacrymans in nature, however it is difficult to distinguish it from the...
J Bech-Andersen, S A Elborne
Dimensional lumber model demonstrates the sensitivity of the particle capture immunoassay in early detection of brown-rot fungi
1995 - IRG/WP 95-20058
A dimensional lumber model was designed to test the sensitivity of the particle capture immunoassay (PCI) compared to traditional methods of culturing and microscopic examination for detection of brown-rot fungi. Southern yellow pine 2 x 4's (5.1x10.2 cm²), and 86.4 cm in length, were inoculated on one end with the brown-rot fungus, Postia placenta, and tested over the full length of the...
C A Clausen, L Ferge
Detection of brown-rot antigens in southern pine
1996 - IRG/WP 96-20090
Brown rot fungal antigens were detected by particle capture immunoassay (PCI) in southern pine 2 x 4's beyond visible or culturable hyphal growth. Further analysis of test samples revealed changes along the 2 x 4's that could be grouped into zones. Zone 1, the point of inoculation through 6 cm, showed low pH, measurable oxalic acid, high moisture, and high protein. Zone 2, throug...
C A Clausen
Hemicellulosic induction of oxalic acid in Postia placenta
1994 - IRG/WP 94-10060
Most studies suggest that enzymes produced by brown-rot fungi are too large to penetrate sound wood structures, even after decay begins. Thus, nonenzymatic agents have been proposed to initiate brown-rot decay. We have reported that the brown-rot fungus Postia placenta MAD-698 initiates a 2-fold decrease in wood pH within 7 days of colonization which is mediated by production of oxalic acid. Strai...
F Green III, M Larsen, T L Highley
Cellular and fractural failure after supercritical fluid impregnation of four wood species
2004 - IRG/WP 04-10503
Supercritical fluids (SCFs) have been investigated for delivering biocides into sawn wood. Pressure differentials during treatment may exceed the compressive or tensile strength perpendicular to grain, creating a potential for transverse deformations that exceed elastic strain limits. Wood treated by SCF processing with CO2, a potential biocide carrier, was inspected macroscopically and microscopi...
M E Anderson, R J Leichti, J J Morrell
Laboratory testing of wood natural durability - In soil-bed assays
1998 - IRG/WP 98-20141
Laboratory methods for assessing wood decay resistance are being investigated in the framework of an ongoing European research project. This paper summarizes the main results obtained for soil-bed tests based on the European prestandard ENV 807-Test 2. The data suggest that this testing methodology is suitable for evaluating the natural durability of timber species in soil-contact under conditions...
R Sierra-Alvarez, I Le Bayon, J K Carey, I Stephan, J Van Acker, M Grinda, G Kleist, H Militz, R-D Peek
A bibliography of the dry rot fungus, Serpula lacrymans
1988 - IRG/WP 1337
For many decades the occurrence of dry rot in buildings has been the cause of serious concern in temperate regions of the world. Consequently, much effort has concentrated on determining the morphology of dry rot and on finding means of prevention and control. During early studies, observers tried to understand the phenomenon of dry rot as a whole, and in the course of the 19th century aspects cha...
G Seehann, B M Hegarty
Trials of new treatments for prevention of kiln brownstain of white pine (Pinus strobus)
1995 - IRG/WP 95-30068
White pine (Pinus strobus) often develops a surface brown oxidative stain when kiln dried. Such stain downgrades high quality lumber and is most likely to occur when fresh, unseasoned lumber is stacked during warm weather prior to kiln drying. Use of reducing agents or pH alteration has been successful, but may have some practical limitations for general use. This study attempted to prevent browns...
E L Schmidt, E Christopherson, T L Highley, M H Freeman
The long road to understanding brown-rot decay. A view from the ditch
1995 - IRG/WP 95-10101
Interest in understanding how brown-rot fungi decay wood has received increasing interest in recent years because of a need to identify novel targets that can be inhibited for the next generation of antifungal wood preservatives. Brown-rot fungi are unique in that they can degrade holocellulose (cellulose and hemicellulose) in wood without first removing the lignin. Furthermore, they degrade holoc...
F Green III, T L Highley
Is laboratory testing of decay resistance questionable as a single criterion for natural durability?
1996 - IRG/WP 96-20096
In a laboratory test set up over 20 hardwood species were evaluated according to the European Standard EN 350-1 including Basidiomycete and soft rot testing. Half of the species used were of a known natural durability. The Basidiomycete testing was carried out using Coriolus versicolor, Gloeophyllum trabeum and Coniophora puteana in a malt agar test similar to EN 113. From this test it was not pos...
J Van Acker, M Stevens, T Van Cauwenberghe, T Seynaeve
Addendum to paper for discussion in Working II
1970 - IRG/WP II 5B
In view of the limited time that will be available for discussions in Nancy, this addendum has been prepared. Arising from the previous collaborative work and Mr Bravery’s visit to most of the co-operating Institutes, a scheme of work entailing tests carried out 1) by a technique chosen by individual Institutes; 2) by an agreed standardised technique would appear to be the best approach. A compl...
J G Savory, A F Bravery
Immuno-electron microscopic localization of extracellular metabolites in spruce wood decayed by brown-rot fungus Postia placenta
1990 - IRG/WP 1441
Degradation by Postia placenta in spruce and birch wood was shown to occur not only in the wood cell wall but also in the middle lamellae region. Middle lamellae was often found to be degraded along the centerline so that cells could separate along this line. Extracellular membrane structures were found surrounding the hyphae and this matrix labelled positively with antisera produced to Postia pla...
Y S Kim, B Goodell, J Jellison
Respiration measurement of dry-rot
1995 - IRG/WP 95-10095
Methods for measuring the production of carbondioxide from wood infected with the dry-rot fungus were evaluated. By enclosing whole wood blocks and measuring the concentration of gas in the headspace by gas chromatography, an exponential increase in the concentration of CO2 was observed for at least 2 months. This technique could therefore present a method for evaluating various treatments of dry-...
L Toft
Susceptibility of CCA treated North American hardwoods to Chaetomium globosum decay
1998 - IRG/WP 98-10278
Seven species of hardwood, Beech (Fagus grandifolia), Basswood (Tilia americana), Maple (Acer rubrum), Oak (Quercus rubra), Trembling Aspen (Populus tremuloides), White birch (Betula papyrifera) and Yellow poplar (Liriodendron tulipifera) were vacuum or pressure impregnated with CCA, at four retention levels. The CCA was allowed to fix in the wood at 35°C. Red pine (Pinus resinosa) was also inclu...
U Srinivasan, Y T Ung, P A Cooper
On the biotope of dry rot (Serpula lacrymans) in the wild
1995 - IRG/WP 95-10123
The True Dry rot fungus was found in the Himalayas several times in this century. The finds were able to cross breed with Serpula lacrymans from Denmark and therefore all belong to this species (Harmsen 1960). In order to understand its successful colonisation in buildings we were interested in studying the natural biotope, i.e. the moisture, temperature and soil relationships. All together 15 fru...
J Bech-Andersen, S A Elborne, K Bech-Andersen
Supercritical fluid treatment: Effects on bending strength of white spruce heartwood
1993 - IRG/WP 93-20008
The effects of supercritical carbon dioxide on wood strength were evaluated using white spruce heartwood, a species known to be especially susceptible to collapse during exposure to higher pressures. The effects of pressures of 2000 or 3600 psig and temperatures of 40 or 80°C were evaluated using 30 or 60 minute exposure periods. No significant differences were noted in modulus of rupture or modu...
S M Smith, J J Morrell, E Sahle-Demessie, K L Levien
Factors affecting decay rates in a fungus cellar II
1986 - IRG/WP 2259
Tests were initiated to investigate the influence of various factors on the decay rate in a "Fungus Cellar". Birch and pine stakes treated with chromated copper arsenate and didecyldimethyl ammronium chloride, as well as untreated control stakes, were incubated in two soils in a Fungus Cellar test and installed at two field sites for comparative purposes. The visual rating vs actual stake weight l...
P A McKaig
Natural durability transfer from sawmill residues of white cypress (Callitris glaucophylla). - Part 1: Optimisation of the extraction conditions
2000 - IRG/WP 00-30238
As the first phase of a large project aimed at recovering 'waste' durability components from sawmill residues of Callitris glaucophylla, several solvents and extraction methods were evaluated, initially in the laboratory and then at pilot industrial scale. Extracts were compared by crude total dissolved solids content, by chemical analysis using GC-MS and LC-MS, and by laboratory...
M J Kennedy, Hui Jiang, L M Stephens
Natural durability transfer from sawmill residues of white cypress (Callitris glaucophylla). - Part 4: Analysis of extracts and treated wood for active components
2000 - IRG/WP 00-20215
In order to facilitate the commercial implementation of a large project aimed at recovering 'waste' durability components from sawmill residues of Callitris glaucophylla, it has been essential to develop analytical methodology for the important bioactive components of the heartwood extract. This methodology will be used 1) to standardise the activity of successive production batc...
Hui Jiang, M J Kennedy, L M Stephens
Targeted inhibition of wood decay (Using everything but the kitchen sink)
1997 - IRG/WP 97-10203
Low molecular weight oxidative decay agents have been implicated in the degradation of wood by brown-rot decay as evidenced by chemical analysis of brown-rotted wood and detection of oxalic acid and hydroxy radicals. Fenton chemistry (H2O2 / Fe++) is often proposed as the mechanism for generating hydroxy radicals. Previous authors have shown iron to enhance the brown-rot hydrolysis of wood, while ...
F Green III, T A Kuster, T L Highley
Fungal colonisation of the keelson and associated structures of a nineteenth century wooden frigate: Concepts of community structure and development
1994 - IRG/WP 94-10072
The early stages of microbial colonization and succession of wooden surfaces exposed to the sea have been extensively studied as have the community structures of archaeological timbers subjected to submergence and then retrieval from the sea. The frigate UNICORN, a largely intact 19th century wooden ship based in Dundee, Scotland, provides the microbial ecologist with a unique opportunity to study...
N A White, J W Palfreyman, G M Smith
Effect of soil type and moisture content on soft rot testin
1986 - IRG/WP 2270
Several soils of different types were tested at a range of moisture contents for their suitability for use in a soil burial soft rot test. Their effectiveness was assessed by weight loss in CCA treated and untreated beech and birch outerwood. A horticultural loam (John Innes No. 2) was the most appropriare soil in terms of amount of weight loss caused, tolerance to changes in soil moisture content...
S M Gray
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