Your search resulted in 1378 documents. Displaying 25 entries per page.
Factors affecting the resistance of fibre building boards to fungal attack
1975 - IRG/WP 252
Fungal decay is initiated at lower moisture contents in standard and tempered hardboards (18%) than in pine sapwood (26%). In contrast, in a saturated atmosphere, the equilibrium moisture contents of standard hardboard (14%) and of tempered hardboard (12.5%) are much lower than the moisture content permitting decay initiation whilst the equilibrium moisture content of pine sapwood (25.1%) approach...
C Grant, J G Savory
Laboratory tests on the residual effects of pyrethroids against termites thirteen years after application
1994 - IRG/WP 94-30056
This paper is in continuation to a series of articles published on the work being developed in Brazil regarding the feasibility of using photostabl synthetic pyrethroids against termites. Tests were carried out to compare the efficacy of five synthetic pyrethroids with the traditional organo-chlorinated pesticide, chlordane. Wooden blocks were impregnated with alcohol-based solutions of the above-...
A M F Oliveira
Leaching from field test stakes. Results from two different methods of analysis
1993 - IRG/WP 93-50013
Field test stakes treated with Boliden K33 containing copper, chromium and arsenic exposed at three different fields in Sweden and rejected due to decay, have in two studies been analysed regarding leaching and remaining preservatives. The stakes have been exposed during 20 to 43 years. The density of the stakes and content of copper, chromium and arsenic have been determined in the top part of th...
F G Evans, M-L Edlund
Effects of heart wood extractives in Dahoma (Piptadeniastrum africanum) on decay resistance to white- and brown-rot fungi
2004 - IRG/WP 04-10536
Dahoma (Piptadeniastrum africanum) is a durable but a lesser utilised tropical hardwood species from Ghana that has the potential of being used as an alternative to Iroko (Milicia excelsa) for many end uses. However, the timber gives off a strong odour especially when wet and during processing. The high durability and the strong odour of the timber could be due to the presence of extractives in th...
Zeen Huang, K Maher, S A Amartey
Bioefficacy of Cunapsol® treated western cedar and southern yellow pine
1996 - IRG/WP 96-30120
Western red cedar and southern yellow pine sapwood were dip treated with a new formulation of waterborne copper naphthenate (Cunapsol®) which complies with VOC regulations. Cunapsol dip treated samples were oven dried at 50°C for 48 hours and then water leached for two weeks. Decay resistance and leachability of preservatives from dip treated specimens were evaluated according to AWPA (American ...
D P Kamdem, M H Freeman, T L Woods
Performance of above ground decay test units treated with a substituted isothiazolone
1989 - IRG/WP 3503
RH 287, a substituted isothiazolone, was evaluated for efficacy against decay fungi in an above ground test in Mississippi. After 45 months of exposure, all test units that were pressure treated with this biocide at levels of 0.026 pcf and higher have no deterioration. In addition, the test units that were dip-treated with a solution concentration of 0.5% also have no deterioration. Compared to pe...
D D Nicholas, J A Wilson, D E Greenley
The influence of UV and IR radiation on leaching of copper and chromium from preservative-treated pine and spruce
1992 - IRG/WP 92-3687
The influence of artifical UV- and IR-radiation on the leaching of copper and chromium components of a CCB-preservative from freshly treated pine and spruce was evaluated. On small pinewood samples it could be shown, that the leaching of copper and chromium can considerabely be reduced by UV-radiation. A Philips HPA lamp type reduced the leaching most effective. IR-radiation lead to higher leachin...
H Militz
Evaluation of extractives from African Padauk (Pterocarpus soyauxii Taub.) for protection of non decay resistant species
2002 - IRG/WP 02-10419
The development of a wood preservative made up of natural extracts is a potentially attractive prospect for the wood preservation industry. In this study, organic solvents were used to remove extractives from African padauk wood samples. The solvent was removed by rotoevaporation, and the total content of the viscous extracts determined to be 54.4mg/ml.
The toxicity of various extracts concentrat...
P Nzokou, D P Kamdem
The resistance of wood coated with different water-borne paints against colonisation by decay fungi
1996 - IRG/WP 96-10165
The susceptibility of wood painted with model paints of known composition to decay fungi was tested without previous weathering. Included in the study were five alkyd emulsion paints and five acrylic paints; one linseed oil paint and two solvent-borne alkyd paints. It was found that several components influenced the susceptibility of these paints. The results of the present study indicate that the...
J Bjurman
A field evaluation of chromated fluoride as a remedial treatment for creosoted wooden distribution poles
1989 - IRG/WP 3556
A commercial chromated fluoride formulation was applied by injection process to previously inoculated creosoted wooden distribution pole sections at a field site in Scotland and appraisal of the efficacy of the formulation against Lentinus lepideus was undertaken at two month and fifteen month intervals. Preliminary results suggest a rapid elimination of organisms from colonised areas. The usage o...
B King, A Bruce
Implications for comparability of laboratory experiments revealed in studies on the effects of population density on the vigour in groups of Coptotermes lacteus (Froggatt) and Nasutitermes exitiosus(Hill) (Isoptera: Rhinotermitidae, Termitidae)
1983 - IRG/WP 1197
(Summary of paper 1194)
The vigour - survival and wood consumption - of groups of Coptotermes lacteus and Nasutitermes exitiosus was measured when termites were kept at different population densities (g termites/ mL) by changing group size and/or volume of the holding container. A characteristic pattern emerged. At low population densities (< 0,01 g/mL) performance of termites improved with an increase in group size; at higher population densities it tended to decline. The impact of altering group size and container volume on termite vigour was most pronounced at low densities; at higher population densities, performance tended to be more stable but declined markedly when termites became overcrowded. In most jar-type experiments on termites, especially those conducted in Europe and the U.S.A., small groups of termites are housed in disproportionately large jars, resulting in very low, sub-optimal population densities. Suggestions are made for improvements in experimental design that would lead to an enhancement of the comparability of results from different laboratories.
M Lenz, R A Barrett, E R Williams
A comparison of shower test results from CCF, CCZF, CCB and Cu-quat treated timber
1995 - IRG/WP 95-50054
The shower test quantifies the amount of specific preservative components which leach from treated timber under simulated open storage conditions. The test method measures leaching from both organic and inorganic salt treated timber. Shower tests of CCF, CCZF, CCB and Cu-quat treated timber which have been performed over the last 5 years by TNO are reviewed and compared. Leached components are qua...
M J Boonstra, A J Pendlebury, P Esser
Biological control in termite management – the potential of nematodes and fungal pathogens
2004 - IRG/WP 04-10521
A brief overview on the options for biological control of termites is presented. Many organisms have been identified as being able to kill termites, however, we do not know their real impact on field populations of termites. Most research has focused on some entomopathogenic nematodes and the fungi Beauveria bassiana and Metarhizium anisopliae. To date, only a limited number of field studies have ...
M Lenz
Estimating the size of subterranean termite colonies by a release-recapture technique
1980 - IRG/WP 1112
The technique is described and the results of an exploratory field trial are presented. The colony size estimate from weekly termite collections varied considerably, but nevertheless permitted assigning termites at three locations to three categories of greatly different colony size. The sizes of the three estimates were much greater than anticipated and included a multimillion termite complex of ...
G R Esenther
Detection of termite attack in wood using acoustic emission
1989 - IRG/WP 2331
Acoustic emission (AE) is the elastic wave produced by the strain energy released in the process of fracture of a material and propagates through it. The object of this report is to detect AEs produced by the termite activities and to evaluate the possibility of using an AE monitoring test to nondestructively detect the termite attack in wood. It was revealed that AEs were detected from the specim...
Y Fujii, M Noguchi, Y Imamura, M Tokoro
Some Experiences with Stake Tests at BAM Test Fields and in the BAM Fungus Cellar
Part 1: Comparison of Results of Visual Assessments and Determinations of Static Moduli of Elasticity (MOE)
2005 - IRG/WP 05-20319
With examples of routine in-ground stake tests differences are shown in the performance of wood preservatives at the BAM test fields Lehre and Horstwalde and in the BAM fungus cellar. Signs of attack of micro-organisms were assessed visually according to EN 252. Periodical determinations of static moduli of elasticity (MOE) revealed the influence of the attack on the elastic properties of the wood...
M Grinda, S Göller
Accelerating effects of the field biological attacks in a weather controled soil bed room
1997 - IRG/WP 97-20118
For the purpose of the accelerating the field evaluation of the material service life, a weather controlled soil bed room were designed. The room was controlled 30°C, 75%R.H. In this room, water was sprayed 15 minutes a day. The workers and soldiers of termite, Reticulitermes speratus, can be penetrated. The comparison results of preservative brushing coated treated stakes between field ones and ...
K Suzuki, I Momohara, T Nishimura
Variation in field test performance of untreated and CCA-treated lesser-known Surinamese wood species
2000 - IRG/WP 00-20213
In Suriname three different field test sites have been used to verify the biological durability of CCA-treated wood and a range of wood species including lesser-known and lesser-used wood species. In total 37 tropical wood species were tested untreated and for 17 of the less durable species CCA-treatments were included as well. Although the three sites are located in the tropical region they diffe...
J Van Acker, M Stevens, L Comvalius
The effect of high and low boron soils on foraging termite behaviour and their metabolic systems
2007 - IRG/WP 07-10602
The highest concentrations of boron are found in ground water and soils of some of the driest climate areas (arid and semi arid regions) in the world. This present study examined the various concentrations of boron levels on filter papers against the subterranean termite species Coptotermes from different provenances and different boron soil levels. The termites were presented with no-choice bioas...
B M Ahmed, J R J French, P Vinden
The role of oxalic acid in tolerance to N’N-naphthaloylhydroxylamine in Tyromyces palustris
2006 - IRG/WP 06-10584
Certain wood decay fungi exhibit tolerance to one or more wood preservatives. Copper tolerance of brown-rot fungi has been studied in our laboratory for the past six years. We have observed some degree of tolerance to N’N-naphthaloylhydroxamine (NHA), a recently patented termite bait, by the brown-rot fungus Tyromyces palustris TYP-6137. In an effort to try and confirm this tolerance in other is...
R A Arango, C A Clausen, F Green III
Future termite control requires partnership between industry, government and people
2006 - IRG/WP 06-10586
Given the behaviour of the pest control industry, together with the housing and timber industries, and performance of the State regulatory agencies, it is not surprising that all of these groups were philosophically ill-prepared to consider alternative measures in June 1995. However, conditions have altered and there is an awareness of such alternatives. In future, termiticides will have propertie...
J R J French, B M Ahmed
Comparative studies of natural durability of Japanese cedar (Cryptomeria japonica D. Don) among the geographic cultivates
2006 - IRG/WP 06-10592
Variation of natural durability of Japanese cedar (Cryptomeria japonica D. Don) (also known as Sugi) was investigated by accelerated tests for decay (Fomitopsis palustris (Berk. et Curt.) Murr.) and termite (Reticulitermes speratus Kolbe) attacks on 13 clones of Sugi trees from Kyushu-Okinawa Region (Fukuka, Ooita, Saga, Miyazaki, Kagoshima). For this purpose, 57 twenty-five years old Sugi trees o...
I Usta, K Takata, S Doi
Decay resistance of coconut and rubber woods. Alternative wood species from Ghana
2006 - IRG/WP 06-10596
With the expanding local and world wide demand for tropical timbers, there is increased interest in the suitability of lesser–used timber species as alternatives for the forest based industries in order to ensure sustainable forest management. In the forests of Ghana, there are quite a number of timber species that are lesser known and have not been adequately used due to the absence of informat...
S Amartey, M Humar, B Donkor, F Pohleven
Resistance of pine and spruce heartwood against decay - The effect of wood chemical composition and coating with water-borne wood oil product
2006 - IRG/WP 06-10597
Natural durability of wood has been widely studied, but the combination of the natural durability and different treatments has not been the focus of many studies. The durability of wooden products is mainly based on the water permeability and the resistance against organisms. In this study, the water absorption and decay resistance of sapwood and heartwood of Scots pine and Norway spruce were exam...
H Viitanen, S Metsä-Kortelainen, T Laakso
The natural durability of wood in different use classes - PART II
2006 - IRG/WP 06-10598
The natural durability of important European wood species has been tested on 3970 speci¬mens in field trials. The wood was exposed at five test sites in Germany with different climates, at each site in European use class 4 and 3 (with and without soil contact). Within European use class 3 three different expositions were tested: vertical with sheltered end grain, vertical unsheltered and horizont...
A O Rapp, U Augusta, K Brandt