Your search resulted in 1437 documents. Displaying 25 entries per page.
Analysis of volatile emissions as an aid in the diagnosis of dry rot
1992 - IRG/WP 92-2393
The dry rot fungus, Serpula lacrymans was grown in pure culture on malt extract and on sapwood of pine. The volatile compounds emitted from the cultures were determined by diffusion sampling on tubes filled with Tenax TA, thermal desorption and gas-chromatography-mass-spectrometry in order to find markers for attack of the fungus....
J Bjurman, J Kristensson
Towards a colour assay of wood degradation
1982 - IRG/WP 2180
A colour assay for the enzyme catalase is described. Since the activity of this enzyme has previously been shown to be correlated with degree of wood degradation as determined by other methods, this assay may provide a rapid quantitative indicator of superficial and internal wood decay....
M A Line
Natural durability of eight tropical hardwoods species from Africa
2005 - IRG/WP 05-10563
Current forest inventory results reveal that there are more than 700 hundred-hardwood species in tropical forests, of which less than 10 percent are harvested and used for commercial purposes. The increased use of lesser-known species can decrease the pressure on current commercial species, increase the value of the forest and lead to better management practices. However basic information on physi...
P Nzokou, K Wehner, D P Kamdem
The preliminary characterization of ß-1,4-xylanase of the brown-rot fungus Gloeophyllum trabeum
1990 - IRG/WP 1447
The extracellular ß-1,4-xylanase of the brown-rot fungus, Gloeophyllum trabeum, was isolated from crude extract by chromatofocusing method (PBE 94 column chromatography). The isoelectric point was estimated to 4.2-4.8 by cromatofocusing and 4.5 by isoelectric focusing (IEF). The molecular weight of the enzyme was estimated to 37,000 dalton by SDS-PAGE. The optimal temperature for the crude extrac...
A-C Ritschkoff, M Rättö, L Viikari
Computer-assisted numerical clustering analysis of various strains of Serpula lacrymans (Wulfen:Fr.) Schroeter apud Cohn
1992 - IRG/WP 92-2396
Eight strains of Serpula lacrymans were compared in relation to their previously determined factors (5 physiological and 10 toxicometrical). A numerical clustering analysis was used along with, as coefficient of similarity, "cos Q" after standardization of all results. Results with respect to the combined factors showed a mutual similarity within four groups of strains. The first of these groups c...
J Wazny, J D Thornton, P Stenzel
Collaborative soft rot experiments 1974. Preliminary analysis of results
1975 - IRG/WP 251
J K Carey, J G Savory
Flow charts for termite and decay tests to determine the natural durability of Japanese cedar (Cryptomeria japonica D. Don)
2008 - IRG/WP 08-20385
This paper deals with the experimental flow charts that were used for determination the effects of fungal decay and termite attack on Sugi heartwood during the course of the study of “Comparative studies of natural durability of Japanese cedar (Cryptomeria japonica D. Don) among the geographic cultivate”, which was carried out by Usta et al (2006)....
I Usta, S Doi
Natural Durability Classification Systems Used Around the World
2009 - IRG/WP 09-10694
Around the world natural durability is classified in different ways. The nature and rigor of the tests used to measure durability, the method of classification based on these data, and use of these classifications to specify end uses or predict service life all vary. This can lead to confusion among people not familiar with the various systems used. This review describes the methods used to classi...
R Stirling
Performance of treated and untreated sawn fence posts of Scots pine and Norway spruce
2000 - IRG/WP 00-30247
Sawn fence posts are a rather important product and the objective of this trial was to assess their durability. In 1985 a field trial with treated and untreated fence posts of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) was set out at the test field in Ultuna, Uppsala, Sweden. The posts had a dimension of 75 x 100 x 1400 mm3. The preservatives applied were a CCA, a...
Ö Bergman
Patterns of bacterial attack in preservative treated eucalypt power transmission poles
1984 - IRG/WP 1223
Patterns of bacterial decay have been examined using light and scanning electron microscopy. Two morphologically distinct patterns have been recognised in preservative treated eucalypt power transmission poles. Bacterial Decay I (BDI) involves the removal of the secondary wall layers initiating with erosion of the S3 layer from the cell lumen. As decay progresses the S2 layer and S1 layer are degr...
G A Willoughby, L E Leightley
The effect of treatment temperature on the biological performance of CCA treated wood
1990 - IRG/WP 3624
Birch and Scots pine sapwood blocks were treated with several concentrations of CCA at three different temperatures: 5, 20 and 35°C. The treated wood was maintained at the appropriate temperature for the fixation period. Leached and unleached samples were then exposed in a soft rot monoculture test using Chaetomium globosum and a brown rot monoculture test using Coniophora puteana. The treatment ...
S M Gray
Water sprinkled pine wood: A microscope study on boards showing streaking
1993 - IRG/WP 93-10033
Boards sawn from the outer sapwood of pine lumber previously water sprinkled for periods of 10-18 weeks and kiln dried, showed streaking after staining. Two types of enhanced stain uptake were noted: 1) a more concentrated and localized form after 10 weeks and 2) a more diffuse type which developed in later stages of water sprinkling. Areas showing enhanced stain uptake were examined using light a...
G F Daniel, T Elowson, T Nilsson, A P Singh, K Liukko
The resistance of wood coated with different solvent-borne paints against colonisation by decay fungi
2009 - IRG/WP 09-40468
This paper examines different solvent-borne paints characteristics and their decay resistance when applied on pine wood surface. It was determined by the standard ENV 839 procedure. The part of samples were subjected to accelerated ageing according to the EN 84 standard. The discussed commercial paint systems were typical stains or penetrating oil-based products, with or without biocides....
B Mazela, P Hochmańska
On the Influence of Wood Destroying Fungi on the Feeding Intensity of Termites
2017 - IRG/WP 17-10893
The baiting and feeding stimulating effect of wood attacked by fungal isolates of the species Coniophora, Lentinus, Poria and Gloeophyllum on termites Reticulitermes santonensis is examined. There are significant relationships between the activity of fungal isolates and the feeding behaviour of termites. The most active isolates can be used for increase the attractiveness of wood to wood-destroyin...
W Unger, T L Woods
Importance of bacteria in the deterioration of archaeological woods
1995 - IRG/WP 95-10122
An electron microscopic study of archaeological woods from different sites and of different ages revealed that the woods had been attacked by erosion bacteria, tunnelling bacteria and soft rot fungi. Bacterial erosion appeared to be most widespread, and was present independently as well as together with tunnelling and soft rot attacks. Thus, in many instances bacterial erosion was the only type of...
Yoon Soo Kim, A P Singh, T Nilsson
Performance if internal remedial treatments to arrest fungal attack in poles and large timbers
2018 - IRG/WP 18-40834
Internal remedial treatments have been used to arrest internal fungal attack in utility poles and other large timbers. Water diffusible systems and volatile fumigants have both been used for this purpose. While both work, it is important to understand the performance attributes of each system. This paper reviews the literature on both systems and makes recommendations for future research....
J J Morrell
Ekki heartwood - is “Durable”
2002 - IRG/WP 02-10444
Severe decay damages of bridges made of ekki (Lophira alata Banks) wood which is classified as a durable species in the EN 350:2 as already reported at the 31 IRG annual meeting. This paper deals with results of long-term decay tests of ekki heartwood specimens using 3 isolates (Loweporus tephroporus 2 strains and a fungus of other sp. from damaged ekki bridges) and Trametes versicolor as a refere...
S Doi, R Itoh, S Horisawa
Ultrastructural aspects of bacterial attacks on an archaeological wood
1993 - IRG/WP 93-10007
Transmission electron microscopy of wood from a Chinese ship submerged in the mud for over 900 years showed bacteria to be the main factor for its deterioration. The micromorphology of degraded wood cell walls was similar to that observed during the attacks of wood by erosion bacteria. Other bacterial forms, previously considered lo be scavenging bacteria, were also abundant in degraded areas of t...
Yoon Soo Kim, A P Singh
Suppression of aerial hypha formation by spent culture filtrate of a non-degradative strain of Postia placenta
1991 - IRG/WP 1498
ME20, a wild-type monokaryotic strain of the brown-rot fungus Postia placenta, does not cause significant weight losses in standard soil-wood block decay tests and fails to form aerial hyphae in liquid and agar culture. This abnormal morphological feature may be caused by the same aberrant physiology that prevents the strain from degrading wood efficiently. ME20 releases elevated levels of the aut...
J A Micales
Effect of permeability and extractives on the decay rate of southern pine sapwood in above grund exposure
2005 - IRG/WP 05-20310
The effects of wood permeability and hydrophilic and hydrophobic extractives on the decay rate of southern pine sapwood in above ground exposure were investigated. Permeability was determined by water sorption measurements, and the effect of extractives was studied by pre-extracting the test samples prior to outdoor exposure using water to extract hydrophilic extractives or sequential methanol/cy...
D D Nicholas, T Schultz, L Sites, D Buckner
Isolation and identification of bacteria from degraded wood - A progress report
1986 - IRG/WP 192
During attempts to isolate tunnelling bacteria in pure culture, physical separation from other bacteria was successfully achieved by the use of cellophane. Cellophane was used in liquid cultures as a substrate for tunnelling bacteria that were present in a mixture with other bacteria. By tunnelling into cellophane, TB were physically removed from contaminating bacteria which could then be removed ...
J A Drysdale, P J Ruland, J A Butcher
Wood degradation mechanisms by the brown rot fungus Gloeophyllum trabeum
1997 - IRG/WP 97-10229
A mechanism for the degradation of wood by the brown rot fungus Gloeophyllum trabeum is outlined. The mechanism includes the function of redox-cycling, low molecular weight phenolic derivatives which sequester and reduce iron in acidic environments. The role of oxalate for the sequestration of iron (hydr)oxides and the pH dependent transfer of iron to the G. trabeum phenolic chelators, as well as ...
B Goodell, J Jellison
Preliminary screening of diffusion formulations for the control of soft rot
1978 - IRG/WP 2104
We have an urgent need in Australia to develop in situ remedial treatments for the present population of in-service transmission poles. For various reasons we have opted for formulations which can be applied as bandage treatments and thus we are primarily concerned with assaying diffusable toxicants. Two basic approaches have been made: an assay of the formulation's toxicity; and a combin...
H Greaves
Natural durability of wood in ground contact - A correlation between field and laboratory tests
1985 - IRG/WP 2182
A field test is being carried out to evaluate the natural durability of 20 hardwoods. The resistance to decay and termite attack was evaluated in accelerated laboratory tests. The results of the field test after 6 years and 8 months indicate that there is not necessarily agreement between results from laboratory and field tests. It is pointed out that apart from the artificiality of the laboratory...
M S Cavalcante, G A C Lopez, R G Montagna, M E S Fosco Mucci
Analysis of degradation observed on ancient wooden objects buried underground
2001 - IRG/WP 01-10403
Ancient wooden objects were sometimes excavated from the moat of mounded tombs in Japan. Such wooden objects were in the shape of a sunshade, bird, shield, pole, yugi(a bag that holds arrows) among others. Archaeologists discussed the usage of such shaped objects, but no one could clearly explain their use. Some objects were observed using an ordinary microscope. Deterioration by bacteria was foun...
H Sakai