Your search resulted in 72 documents. Displaying 25 entries per page.
Future insecticidal treatments for wood products
1980 - IRG/WP 3140
Protective measures involving chemical treatment of wood use only a narrow range of toxic materials which are divisible into two groups, (i) those that are water-soluble, (ii) those that are soluble only in organic solvents. It is generally true to say that, as far as protection against insects is concerned, the former are stomach poisons while the latter are largely (though not exclusively) conta...
D J Cross
Administration of wood preservative usage in New Zealand
1977 - IRG/WP 395
Principal administration of the preservative treatment of timber in New Zealand is by the Timber Preservation Authority (TPA). The TPA was established in 1955 by Act of Parliament and is under the jurisdiction of the Minister of Forests who appoints its members. Its field staff are Forest Service employees. The Authority comprises twelve members and includes representatives of timber trade associa...
M E Hedley
Benzalkonium chloride (an AAC preservative): Criteria for approval, performance in service, and implications for the future
1985 - IRG/WP 3328
The data base generated for benzalkonium chloride was considered adequate for commercial approvals, particularly after revision in late 1982. Field trials, although not part of the approval criteria, generally supported commercial use; decay observed in one test (post and rails) after 6 years' exposure would have resulted in some caution in setting retentions. No laboratory trial, nor fie...
J A Butcher
Gaseous preservative treatment of wood
1990 - IRG/WP 3631
A recent development in processing wood with a gaseous preservative means that dry, treated wood can be produced in under 30 hours with the benefits of product diversification, faster stock turnover and the ability to respond to short term demand. About 400,000 m³ of wood are treated each year in New Zealand with boron salts to protect from borer infestation. Traditionally this treatment is effec...
R Burton, A J Bergervoet, K Nasheri, P Vinden, D R Page
Fumigation of red beech in New Zealand for prevention of graystain
2000 - IRG/WP 00-10343
The discoloration of sapwood of red beech (Nothofagus fusca) after drying has been an ongoing problem which may lower value of material for certain applications (such as flooring) by as much as 50%. The dark gray stain noted after the drying and planing of lumber is not prevented by fungicide dips, and is most likely similar to the enzyme-mediated stain noted in a variety of commercial hardwoods. ...
E L Schmidt, B Kreber
Comparative performance of copper azole and copper-chrome-arsenate treated rubber wood in Australian, Malaysian and New Zealand tests sites
2000 - IRG/WP 00-30213
Rubberwood (Hevea brasiliensis) has been used for non-structural products where appearance is important. It has rarely been used for structural uses where preservative treatment is required. In order to evaluate the in-ground durability of preservative-treated rubberwood, test stakes (20 x 20 x 500 mm3) were treated to four retentions of CCA and copper azole (Tanalith® E) and installed in test si...
J A Drysdale, M E Hedley, E Loh, L T Hong
Leaching tests on CCA-treated wood using inorganic salt solutions
1984 - IRG/WP 3310
Pinus radiata sapwood treated to approximately 10 kg/m³ with Tanalith NCA or Tanalith C-type CCA preservatives was ground to a fine powder and samples were then leached with solutions of calcium chloride, calcium nitrate, magnesium nitrate, or a mixture of potassium di-hydrogen orthophosphate and di-potassium hydrogen orthophosphate, at 0.03M-1.00M solution concentrations. Leached wood samples we...
D V Plackett
Performance of boron-treated radiata pine in above ground field tests in New Zealand
2006 - IRG/WP 06-30406
Boron treatment was approved for exterior, above ground use in New Zealand in 1958, provide treated commodities were painted with a three-coat paint system. Above ground tests of rail units and L-joints were established at the NZ Forest Research Institute (now Scion) between 1967 and 1980 to monitor performance of boron treatment in relation to that of untreated and CCA-treated timber.
Results sh...
M Hedley, D Page
Above and Below-Ground Depletion of Copper, Chromium and Arsenic from Pinus radiata and Fagus sylvatica at Thirteen Test Sites in New Zealand and Australia
2006 - IRG/WP 06-30402
The objective was to determine the significance of site and wood species on preservative depletion for a copper chrome arsenate preservative (CCA) from 20 x 20 x 500 mm field test stakes after 5.5 and 4.5 years for pine and beech respectively. At least 5 sacrificial stakes were used to produce site means. Site and wood species had a major effect on copper, chromium and arsenic loss from CCA treate...
R Wakeling
Wood decay fungi from New Zealand ‘leaky’ buildings: PCR identification and laboratory decay tests of wood preservative-treated Pinus radiata (Part 1)
2007 - IRG/WP 07-10620
Fungi colonising Pinus radiata D. Don framing timber of ‘leaky’ New Zealand buildings were isolated to produce pure cultures. Mycelia from these cultures on agar media were collected to extract DNA. To identify the fungi to the species level, polymerase chain reaction (PCR) with primer pairs ITS1-F and ITS4 were performed followed by sequencing of the internal transcribed spacer (ITS) region. ...
D Stahlhut, R L Farrell, R Wakeling, M Hedley
Wood decay fungi from New Zealand leaky buildings – PCR identification (Part 2) and aerial spore trapping
2008 - IRG/WP 08-10649
Prior to this study, it was not know which species of decay fungi caused decay in New Zealand leaky buildings. Use of molecular biology methodology, polymerase chain reaction (PCR), and subsequent DNA sequencing, as well as classical mycological techniques based on morphology, has enabled identification of decay fungi and has provided insight into their relative importance based on isolation frequ...
D Stahlhut, R L Farrell, R Wakeling, M Hedley
Above and Below-Ground Copper-Azole and Copper, Chrome Arsenate Depletion from Pinus radiata and Fagus sylvatica at Thirteen New Zealand & Australian Sites
2008 - IRG/WP 08-30460
The objective was to determine the significance of site on preservative depletion from Pinus radiata D. Don and Fagus sylvatica L. 20 x 20 x 500 mm field test stakes treated with a ground contact retention of copper amine plus tebuconazole (CuAz) and copper chrome arsenate (CCA) after approximately 5 years exposure to widely different soil and climate conditions. Site, wood species and their inter...
R Wakeling
Discovering anti-fungal agents in New Zealand native plants for use in wood protection
2009 - IRG/WP 09-10692
Extracts from Hinau (Elaeocarpus dentatus) leaves were tested in the laboratory for antifungal activity. In addition, the anatomical structure of the leaf was also examined by a combination of light and scanning electron microscopy. Chemical characterisation of the extracts and investigation into potential use of its components for wood protection is underway. A combination of light microscopy (...
C Rickard, T Singh, A Singh, R Newman
A Method for Studying Boron Redistribution and Leaching in Timber Framing
2011 - IRG/WP 11-20476
In typical New Zealand timber framed house construction, the timber framing has a vapour permeable building wrap applied to the exterior and a cladding applied over 20 mm battens. An interior lining usually of gypsum plasterboard is then fixed once the timber framing has a moisture content of < 20%. Timber framing within the building envelope is not expected to be wet in-service or exposed to a le...
J A Drysdale, N Marston, M E Hedley
Comparison of rates of wood decay from four different field test protocols following 4-5 years exposure at a site in New Zealand
2011 - IRG/WP 11-30565
The rate of decay of Pinus radiata was evaluated using four different field test protocols at a site near New Plymouth, New Zealand. The average Scheffer index was 86 over the five year period of testing. The field tests were an in-ground stake test (AWPA Std E7-01) and three above ground tests – lap-joint (AWPA Std E16-98), decking (AWPC protocol) and ground proximity tests (AWPA Std E18-06) T...
P Lobb, K Day, A Siraa
Glueline fungicides in veneer based engineered wood products - results from laboratory work for the H1.2 hazard class in New Zealand
2012 - IRG/WP 12-30593
The use of glueline insecticides in plywood and laminated veneer lumber is commonplace in several countries. However, few glueline fungicides are registered for commercial use with previous work suggesting that achieving control of decay from the glueline is very challenging. This paper summarises two tests completed on Pinus radiata plywood with a new glueline fungicide comprising the active in...
A Siraa, K Day, P Lobb
Natural durability of plantation-grown coast redwood (Sequoia sempervirens) in New Zealand
2014 - IRG/WP 14-10817
There is wide variation in the wood properties of plantation-grown coast redwood in New Zealand. Contributing factors are the seed source, silviculture, growth and age of the trees in the plantation forests. Little is known about how these factors affect the variation of wood properties among and within the trees of New Zealand’s coast redwood forests. Heartwood of plantation-grown coast redwood...
D O’Callahan, T Jones, C Low, C Chittenden
An update on durability of New Zealand grown timber
2015 - IRG/WP 15-10851
Classification and predication of in-service performances of naturally durable timber is much more difficult than preservative treated timber due to the variability of wood properties within and between trees of the same species and the variable nature of the hazard to which the timber will be exposed. A combination of field test and in-service testing has been used to classify the suitability of ...
D Page, T Singh
A summary of history and use of timber bridges in New Zealand
2017 - IRG/WP 17-40801
Wooden bridges have been an important part of road and rail networks in New Zealand. While wooden structures have largely been replaced by concrete and steel on major arteries they still have a place where lightweight, easily assembled structures are needed. These timber bridges may also be a cheaper alternative to other materials in roads which carry relatively low traffic loads. In the last ten ...
D Page, T Singh
Above-ground testing methods – review of Rotorua, New Zealand test site results after ten years
2018 - RG/WP 18-20642
A series of seven different types of above ground durability tests were initially conducted over four years to determine which type of tests would give the fastest, most consistent results. Five types of test; ground proximity, two types of decking, flat panels and double layer, were reassessed after ten years. Exposure conditions varied between tests with ground proximity producing close to groun...
D Page, T Singh
Glueline fungicides in veneer based engineered wood products – updated results from laboratory work for the H1.2 hazard class in New Zealand
2018 - IRG/WP 18-30726
Results from New Zealand H1.2 ‘bin’ trials containing plywood glueline treated with triadimefon and cyproconazole were reported in 2012 (IRG/WP 12-30593). One of these trials has continued to the present day (2108) and updated results of this trial are reported. The triadimefon and cyproconazole glueline treatment continues to compare with, or outperform, the reference preservative used, bei...
A Siraa, K Day, B Kibby
Suitability of boron preservative treatment of minor species as framing in New Zealand buildings
2023 - IRG/WP 23-30778
The inclusion of alternative species to radiata pine, predominantly exotic species, in the building code (NZS 3602) raises questions as to whether they require preservative treatment and, if so, whether they can be adequately treated using current industry processes.
Early research with boron indicated that the dip/diffusion method for green timber would give adequate preservative retention in sa...
D Page, I Simpson, T Singh