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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


Severe decay damages of bridges made of ekki (Lophira alata) wood known as a durable species
2000 - IRG/WP 00-10383
Bridges made of ekki (azobe, bongossi, Lophira alata Banks et Gaertn.) timbers were severely decayed only 10 years after the construction possibly caused from no maintenance for the periods. The reason of no maintenance is due to the misunderstandings on wood durability against wood-decaying fungi. Some civil-engineers and architectures understand "durable species" means "absolutely decay-durable ...
S Doi, T Sasaki, Y Iijima


Laboratory culturing and decay testing with Physisporinus vitreus and Donkioporia expansa orginating from identical cooling tower environments show major differences
1996 - IRG/WP 96-10184
Both Basidiomycete fungi Physisporinus vitreus (Pers.:Fr.) P. Karst. and Donkioporia expansa (Desm.) Kotl. & Pouz. were isolated from identical cooling tower environments. Azobé heartwood (Lophira alata), a very durable tropical wood species was totally deteriorated in cooling towers in a similar way by both fungi. First attempts to culture Physisporinus vitreus in laboratory circumstances sh...
J Van Acker, M Stevens


Highly virulent wood-rotting Basidiomycetes in cooling tower timbers
1995 - IRG/WP 95-10125
Over the past ten years most industrial cooling towers changed their water treatment systems in order to meet environmental requirements. Since this alterations wood rot attack has been reported more frequently. Several Basidiomycete fungi were isolated and determined. Amongst the most important ones are strains of Physisporinus vitreus (Pers.:Fr.) P. Karst., Phellinus contiguus (Fr.) Pat. and Don...
J Van Acker, M Stevens, V Rijckaert


4th Report on condition of panels at Sekondi, Ghana
1978 - IRG/WP 445
F F K Ampong


Laboratory tests on the natural durability of timber methods and problems
1984 - IRG/WP 2217
In literature a large variety of test methods is mentioned to examine the natural resistance of timber against fungal attack. This concerns the kind of sampling as well as the test procedure, the test fungi, the duration of test, and the classification of the resistance according to the test results. These variations, however, are of great influence on the test result. Long term exposure will lead...
H Willeitner


Field tests of different tropical wood species in sea water
2022 - IRG/WP 22-30773
A number of tropical timbers have been tested according to EN 275 at Kristineberg Marine Research Station in Sweden since 1999. Most of these tests have started during the last 5-8 years. Wood species included have been Lophira alata (Azobé/Ekki), Minquartia guianensis (Manwood/Acaria), Chlorocardium rodiei (Greenheart), Cyclodiscus gabonensis (Okan/Denya), Shorea spp. (Bankirai), Dicorynia guia...
M Westin, P Larsson Brelid


Water-based water repellents for treatment of wood
1987 - IRG/WP 3446
The water uptake by wood can be reduced by treatment with a water repellent. The water repellents most commonly used are solvent based. In the present work a new type of water repellent that is water-based has been investigated. Two different treatments have shown an effect of the same order as a commercial solvent based product. The cellular distribution of the water repellents has been investiga...
I G Svensson, G Hägglund, I Johansson, W B Banks


Copper binding capacity of modified wood flour
1992 - IRG/WP 92-3709
Wood flour was modified by reaction with oxidising agents and CCA preservative. The copper chromium and arsenic were removed from the CCA treated wood flour by an acid leaching procedure. The modified wood flours were allowed to react with copper acetate solution and the level of copper fixation achieved was determined. The modified wood flours had greater affinity for copper ions present in solut...
N C Milowych, W B Banks, J A Cornfield


The colonization of selected naturally durable timbers by marine fungi and borers
1977 - IRG/WP 439
In recent years, concrete and metal have been widely substituted for wood in contact with sea water, but wood products have not lost their usefulness under such conditions. In many cases, wood if sound and durable, may prove to be the most practical and economical of materials used in sea water exposure. Timber when immersed in the sea may be attacked by micro-organisms (bacteria and fungi) and ma...
S E J Furtado, E B G Jones


Paper for discussion - Incising of spruce to improve preservative penetration
1973 - IRG/WP 318
Large quantities of whitewood or Norway spruce (Picea abies) are regularly imported into the United Kingdom from continental Europe. In addition, increasing amounts of Sitka spruce (Picea sitchensis) are likely to become available over the next decade from the Forestry Commission. In many ways spruce is a good structural timber, eg it is relatively cheap and easily available, it has adequate stren...
W B Banks


The degradation of wood surfaces by water
1984 - IRG/WP 3289
Thin radial/longitudinal sections (~100 µ) of Scots Pine (Pinus sylvestris) and lime (Tilia vulgaris), were exposed to deionised water over the temperature range 25-65°C. Losses in wet tensile strength and toughness occurred rapidly at temperatures from about 50°C upwards. After about 2 months' exposure pine lost some 10-30% of its tensile strength and 20-60% of its toughness. For lime...
W B Banks, P D Evans


Alternative timbers to Iroko (Milicia excelsa) for various end-uses: Ghana’s offer
2004 - IRG/WP 04-10518
There are hundreds of timber species indigenous to Ghana and several exotic species have been extensively planted. The timber industry in Ghana is very important to the country’s economy. Despite its small size relative to the world trade in timber products, it has the potential to be a driving force in the development of the Ghanaian economy. The industry is currently going through a period...
S A Amartey, Zeen Huang, A Attah


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


End grain sealing by polymer impregnation
1992 - IRG/WP 92-3708
The solution and dispersion characteristics of several hydrophobic derivatives of cellulose have been studied and the abilities of these polymers to afford effective end grain sealing of Corsican pine have been examined. Both solution and dispersion treatments with ethyl cellulose imparted good water repellency and end grain sealing to wood samples, however, the disperse systems possessed lower vi...
J M Lawther, W B Banks, D G Anderson, J A Cornfield


The degradation of wood surfaces by dilute acids
1985 - IRG/WP 3326
Thin radial/longitudinal sections(~100 µ) of Corsican Pine (Pinus nigra) and Lime (Tilia vulgaris), were exposed to Sulphuric, Sulphurous, nitric, acetic, and formic acid at 40°C in the pH range 2-6. After about 3 months exposure to Sulphuric, nitric, acetic and formic acid at pH 2.0 Pine lost some 20-25% of its tensile strength. Losses in tensile strength due to sulphurous acid were greater bei...
P D Evans, W B Banks


A substantively bonded water repellent treatment based on chromium carboxylates
1985 - IRG/WP 3344
Chromium carboxylates soluble in toluene have been synthesised and applied to Scots pine (Pinus sylvestris) sapwood. Without any further treatment, the compounds may be readily leached from wood surfaces with toluene. After a period of heating however, they become fixed to the cell wall, substantial amounts being resistant to leaching even under reflux conditions for several hours. Treatment of wo...
J K Wright, W B Banks, W J Eilbeck


Borer fauna of Iran biodeterioration of wooden boats in Persian Gulf and Sea of Oman
1997 - IRG/WP 97-10230
In Persian Gulf and Sea of Oman (Indian Ocean) there are thousands of wooden boats from the time of Acheamenian and Sassand dynasti when India was a part of the Persian Empire. Now after 2500 years again, the Indian timbers specially Tectona Grandis and other Indian timbers and also tropical woods of Zanzibar (Tanzania) are brought to the Persian Gulf and Sea of Oman (Indian Ocean). Unfortunately ...
P Niloufari


Changes in bacterial gut community of Reticulitermes flavipes (Kollar) and Reticulitermes tibialis banks after feeding on termiticidal bait material
2014 - IRG/WP 14-10819
In this study, 454-pyrosequencing was used to evaluate the effect of two termiticidal baits, hexaflumuron and diflubenzuron, on the bacterial gut community in two Reticulitermes flavipes colonies and one Reticulitermes tibialis colony. Results showed two bacterial groups to be most abundant in the gut, the Bacteroidetes and Spirochaetes, both of which do not appear to be adversely affected by bait...
R A Arango, F Green III, K F Raffa