Your search resulted in 165 documents. Displaying 25 entries per page.
Qualifying ecotoxicity research on tropical hardwood leachates
1997 - IRG/WP 97-50096
Almost as a rule, quantification and identification of various types of environmental contamination is grounded on chemical evaluation principles. Yet for monitoring surface water pollution, aquatic bio-assays may provide a more direct way to assess the potential hazard of environmental samples. A battery of such tests is experienced onto leachates of tropical hardwoods used in ground and water co...
G M F Van Eetvelde, P Marchal, M Stevens
Evaluation of the european standard ENV 12038 for durability testing of plywood
2001 - IRG/WP 01-20237
The latest improved version of the standard ENV 12038 drafted as document N44 by CEN Technical Committee 38 (WG 7 - WG 23) is used to evaluate the effect of wood composition and structure on plywood durability. The method described is based on the agar-block test of the EN 113 standard used for the determination of the efficacy of wood preservatives and the assessment of the natural durability of ...
J Van Acker, M Stevens, E De Clercq
The WOODCARE project: Development of detection methods for Death watch beetle larvae and fungal decay
1999 - IRG/WP 99-20172
Woodcare was a European project coordinated by English Heritage. The aim of the research was to develop more targeted and more environmentally friendly treatment methods for Death watch beetle infections in Oak constructions of historical buildings. TNO has developed two new methods for fast and reliable detection of Death watch beetle larvae and related fungal decay in Oak. The problem with Death...
P Esser, P Van Staalduinen, A C Tas
Treatment of poplar plywood with solvent and water-borne preservatives
1989 - IRG/WP 3538
Poplar as a light hardwood is appropriate for plywood production. Owing to its low natural durability it is generally recommended to preserve it in all conditions where risks of fungal attack may be present. A research project has been carried out on preservative treatments of plywood commodities. Parameters studied were various treatment cycles, three types of plywood, and a number of solvent and...
J Van Acker, M Stevens
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
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
The effect of pretreatments on the impregnation of air-dried sawn Belgian spruce
1988 - IRG/WP 3490
In general the impregnation of airdried spruce results in a variable treatment and limited penetration. This is the result of pit aspiration that occurs during drying of the spruce sapwood and heartwood. Spruce timber is becoming of greater importance in Belgium and hence research for better treatment of this vulnerable wood species is needed. Squared airdried timber of different dimensions were e...
J Van Acker, M Stevens
Laboratory trial to identify potential in-forest treatments to control fungal pre-infections of radiata pine logs
2000 - IRG/WP 00-30220
Development of fungal infections of radiata pine logs by wood degrading fungi commences immediately after tree felling. In general, subsequent antisapstain treatments are unable to control fungal degrade on logs where the pre-treatment log storage time exceeds 2-5 days. However, use of an in-forest treatment of logs may be advantageous to log exporters to control fungal pre-infections during the p...
D R Eden, B Kreber, R N Wakeling, J G Van der Waals, C M Chittenden
Effect of bioextracts on colonisation of radiata pine sapwood by three sapstain fungi
2003 - IRG/WP 03-10485
The objective of this study was to investigate the effect of aqueous bioextracts prepared following two-week incubation of forest soil, garden compost and chicken manure respectively, on the ability of Ophiostoma flocossum, Leptographium procerum and Sphaeropsis sapinea to colonise unseasoned radiata pine sapwood.
The research showed that all bioextracts tested retarded the rate of fungal colonis...
J van der Waals, C Chittenden, B Kreber
Leachabilty and efficacy of fatty acid derived boron esters as wood preservatives - leachability and efficacy of fatty acid derived boron esters as wood preservatives
2004 - IRG/WP 04-30351
Borates have many advantages as wood preservatives. However, boron is susceptible to depletion under humid conditions and this restricts its outdoor use. In order to reduce boron leachability in treated wood, one of the anticipative approaches is to use organic fixed boron-based preservatives. This study investigated the leachability of six boron ester compounds as potential preservatives. Scots p...
A Mohareb, J Van Acker, M Stevens
Environmental fate of copper-based wood preservatives in different soil substrates - Part 1: Screening of the metal adsorption potential
1998 - IRG/WP 98-50101-21 a
In treatment plants, spillage of wood preservatives onto soil may be of environmental concern. This potential soil contamination served as an objective for a screening study. Three different mineral soils, a mineral substrate and two horticultural substrates are examined for their sorptive potential of copper through mixing with wood preservative solutions.
Depending on the soil/substrate charact...
G M F Van Eetvelde, J M Mwangi, F Tack, R Hartmann, M Stevens
Time limits for holding logs to achieve successful antisapstain treatment
1997 - IRG/WP 97-30126
The purpose of these trials was to determine the maximum time that logs can be left in winter and summer before treatment if sapstain, caused by pre-treatment infection, was to be prevented. Pre-treatment storage conditions representative of average temperature and humidity for the winter months of June, July and August, and of moderately severe summer conditions, for the Bay of Plenty, New Zealan...
D R Eden, R N Wakeling, C M Chittenden, J G Van der Waals, B Carpenter
Creosote losses due to ageing methods prior to laboratory efficacy testing
2002 - IRG/WP 02-20256
Laboratory efficacy testing of creosote is affected by the impact of volatile components on the fungal growth. European test methods for assessing efficacy against Basidiomycetes and soft rot fungi is based on two standard methods, EN 113 and ENV 807 respectively. Combined with both fungal tests two pre-treatment methods are commonly used, namely EN 84 (leaching) and EN 73 (evaporation). Within th...
J Van Acker, K Ghekiere, M Stevens
Variable tolerance of Ophiostoma spp. and Diplodia pinea to commercial antisapstain products
1998 - IRG/WP 98-10266
A recent survey of the occurrence of sapstain fungi in New Zealand, conducted at The University of Waikato, provided the opportunity to examine fungicidal tolerance amongst new isolates. It also enabled a comparison of tolerance amongst new isolates with those used in routine antisapstain screening trials at Forest Research.
A rapid antisapstain laboratory disc trial was used to determine the ext...
D R Eden, C M Chittenden, B Kreber, J G Van der Waals, R N Wakeling, R L Farrell, T Harrington
Artificial weathering exposure as an alternative for standard ageing according to EN 84 (leaching) and EN 73 (evaporation)
2002 - IRG/WP 02-20254
In order to verify potential weaknesses of wood preservatives fungal tests are carried out after ageing of wood preservative treated test blocks. The European standard EN 599 as a framework for efficacy assessment of wood preservatives includes the use of two ageing methods prior to fungal testing, namely a leaching method (EN 84) and an evaporation method (EN 73). The European research project "F...
J Van Acker, M Grinda, D J Dickinson
Effect of origin and orientation of Radiata pine substrates on the development of fungal degrade
2000 - IRG/WP 00-30221
The objective of this study was to determine the influence of different radiata pine substrates on colonisation by sapstain fungi. Freshly-cut branch wood, stem wood and sawn lumber were used to prepare test samples with the largest wood surface area showing a transverse, radial or tangential face. Test samples were evaluated against sapstain fungi using a rapid laboratory antisapstain screening m...
B Kreber, D R Eden, C M Chittenden, B Carpenter, J G Van der Waals
Sentry®), a new antisapstain formulation for protecting logs and lumber. - Part 1: advances in protection of New Zealand radiata pine logs
1999 - IRG/WP 99-30188
Until recently antisapstain formulations gave approximately 10 weeks protection to radiata pine logs and even within this time frame protection was often not consistent. Industry requires 20 weeks protection. The degree of protection sought by industry is in the order of 90-95%. For example, this equates to a maximum of 5 - 10% surface cover of sapstain in the first whole veneer produced from a pe...
R N Wakeling, D R Eden, C M Chittenden, J G Van der Waals, B Carpenter, I Dorset, R Kuluz, J Wakeman, T Price, B Nairn
The accelerated L-joint test method for determination of the out of ground natural durability
1998 - IRG/WP 98-20146
The accelerated L-joint test incorporates a moistening device and uses a close end water trap in an open joint connection with a laminated tenon member consisting of the perishable reference wood species scots pine sapwood and beech.
After one year of exposure it is possible to show a distinct identification of natural durability classes 4 and 5 against the more durable wood species. Both weight ...
J Van Acker, C Brauwers, M Stevens
The lasting dehydration of wood treated by bifluorides worked up in Diffusec noticed by a continual drying of the wood
1999 - IRG/WP 99-30196
After an immersion of sound wood in a solution of Diffusec, in which a combination of acid potassium and ammonium bifluorides = FHF- in dissociated form is present, their potassium and ammonium fluoride ions together with the bifluoride ion = (FHF-) diffuse into the wood. They make use of the woodmoisture available as O-H-O bonds directly attached to the cellulose in the wood fibres to attract the...
H F M Nijman
Environmental risk assessment of wood preservatives in the Netherlands
2001 - IRG/WP 01-50166-10
Before biocides can be introduced to the Dutch market, they have to be authorised under the Pesticides Act (1962). The criteria for authorisation of biocides have been laid down in the Dutch Decree on Environmental Requirements for the Authorisation of Pesticides Used in Fields Other than Agriculture. In 1998, the EU Biocides Directive (98/9/EC) entered into force, and it was implemented in May 20...
E Smit, P van der Zandt, J Appelman
Genetic Engineering in tree breeding
1998 - IRG/WP 98-10294
The genetic improvement of forest trees by classical breeding is a slow process in comparison with that of annual crops. Tree breeding however is of great importance and has led to trees with better growth characteristics and better disease resistance. An important wood characteristic which has been neglected in breeding programs is wood durability. The durability of the wood will determine for wh...
J Van Doorsselaere, H Beeckman, M Van Montagu, W Boerjan
Standard and accelerated testing of boron-additive wood protection systems
2005 - IRG/WP 05-30381
The main objective of this research was to determine the effectiveness of boron-additive protection systems for above ground applications by means of field testing. The two field test procedures used are based on the L-joint test described in the European standard EN 330. For the first set up the boron treated timber was coated in accordance with the standard EN 330 system. The second set up is ba...
A Mohareb, J Van Acker, M Stevens
A new concept for the evaluation of wood durability for out of ground contact using accelerated L-joint testing
1997 - IRG/WP 97-20123
Since the wood preservation sector is developing in favour of defining exactly the utilization of wood products and preservation techniques as a function of the envisaged hazard class, more in particular the hazard classes 3 and 4 (EN 350) there is obviously a need for a test method evaluating natural durability for out of ground contact applications. Based on the L-joint test as described in the ...
J Van Acker, M Stevens
Increased biological durability differs for traditional wood preservation and new non-biocidal systems (NBS)
2000 - IRG/WP 00-20212
Wood preservation is a way to increase the biological durability of wood by the addition of chemical components with a biocidal effect. The effect of such treatment is clearly concentration dependent. At distinct levels of fungicide concentration fungi are killed or inhibited in their enzymatic functioning to provide nutrients. The toxic limits allow decision-makers to provide treating prescriptio...
J Van Acker, M Stevens
The development of blue stain in service in sapwood of European softwood species
1997 - IRG/WP 97-10236
The utilisation of softwood species for window joinery applications is gaining importance in countries frequently using tropical hardwood species up to now. Since wood preservation is not always part of the total concept of window frames manufactured from sapwood containing wood elements it is essential to know the impact of durability on the performance. Moisture content control is a major tool i...
J Van Acker, R Klaassen, H Militz, M Stevens