Your search resulted in 27 documents. Displaying 25 entries per page.
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
The Influence of Extractives on Western Redcedar’s Equilibrium Moisture Content
2006 - IRG/WP 06-40331
The high natural durability of western redcedar (Thuja plicata Donn) heartwood is often attributed to the presence of the thujaplicins, which are toxic to fungi. However, sound, twenty-five year old western redcedar shakes and shingles were found to contain only traces of the thujaplicins, but significant quantities of plicatic acid (which is only weakly toxic to fungi). This suggests that factors...
R Stirling, P I Morris
Methods for Determining the Role of Extractives in the Natural Durability of Western Redcedar Heartwood
2007 - IRG/WP 07-20356
The durability of western redcedar heartwood is influenced by a number of different extractives operating by different mechanisms. In order to guide a systematic isolation of extractives with high fungal toxicity, a micro-bioassay has been developed for measuring the fungal toxicity of extractive fractions. Two additional assays quantify the anti-radical and metal chelating properties of cedar ext...
R Stirling, C R Daniels, J E Clark, P I Morris
Micro-Distribution of Micronized Copper in Southern Pine
2008 - IRG/WP 08-30479
For copper-based preservatives to be used in ground contact, penetration of copper into the cell wall is believed to be important to protect the wood from soft rot fungi. Preservatives containing soluble copper are known to do this. It is not known whether preservatives containing particulate copper will also migrate into the cell wall in sufficient quantities to control soft rot decay. An AWPA st...
R Stirling, J Drummond, Jun Zhang, R J Ziobro
Re-Distribution of Copper in the Cell Walls of Wood Treated with Micronized Copper Quat
2009 - IRG/WP 09-30506
Wood treated with copper-based preservatives to be used in ground contact may fail to inhibit soft rot fungi if penetration of copper into the cell wall is insufficient. Preservatives containing soluble copper are known to penetrate the cell wall; however, it is not known whether preservatives containing particulate copper will also migrate into the cell wall in sufficient quantities to control so...
R Stirling, J Drummond
Degradation of Carbon-Based Preservatives by Black-stain Fungi
2010 - IRG/WP 10-30533
Some black-stain fungi are known to exhibit resistance to carbon-based preservatives. However, the cause of this resistance is unclear. The fungi may have mechanisms to tolerate these chemicals, or they may be able to degrade and detoxify them. Fungi capable of degrading carbon-based preservatives are of interest for possible bioremediation of carbon-based preservative-treated wood at the end of i...
R Stirling, P I Morris
Mobility of Copper from MCQ in Shell-Treated Wood Exposed Above Ground
2010 - IRG/WP 10-30534
Most Canadian treated decking in service has been given just a thin shell of preservative treatment but it has still performed very well. This is because copper migrated into checks and prevented germination of basidiospores on the freshly exposed untreated wood. Unlike soluble copper systems, MCQ has its copper primarily in the form of small basic copper carbonate particles. For MCQ to be effecti...
R Stirling, P I Morris
Phytosanitary standards and the potential for acceptance of chemical treatments as a phytosanitary measure
2011 - IRG/WP 11-30558
Regulations governing international trade in forest products must balance the economic and social benefits of trade with the potential risks of transporting invasive species. The International Plant Protection Convention (IPPC) is an international agreement intended to manage this process. It develops international phytosanitary standards (ISPMs) that are recognised by the World Trade Organisation...
A Uzunovic, R Stirling, J J Morrell, P I Morris, C F Schauwecker
Extractives in Norwegian-Grown and North American-Grown Western Redcedar and Their Relation to Durability
2012 - IRG/WP 12-10762
The extractives responsible for the natural durability of western redcedar (WRC) are not well understood. Recent work by the Norwegian Institute of Wood Technology and the Norwegian Forest and Landscape Institute has evaluated the natural durability of Norwegian wood species and reference species, including Norwegian-grown WRC and North American-grown WRC, in a series of decay tests. The availabil...
R Stirling, P O Flæte, G Alfredsen, P I Morris
Inhibition of Basidiospore Germination by Copper from MCQ, ACQ and CCA Leachates
2012 - IRG/WP 12-10778
The long-term decay resistance of refractory wood shell-treated with chromated copper arsenate (CCA) in above-ground exposures has been attributed to mobile copper that migrates into checks and inhibits the germination of basidiospores. Copper from micronized copper quat (MCQ) has also been shown to migrate into checks suggesting similar performance as a shell treatment, but questions have been ra...
R Stirling, J Drummond, P I Morris
Performance of Coatings on Wood Treated with Carbon-Based Preservatives
2013 - IRG/WP 13-40638
Wood treated with carbon-based preservatives is often used in applications where coatings are required, yet few studies have examined the effect of such treatment on coating performance. Users need to be confident that coatings on carbon-based preservative-treated wood will perform as well as or better than those on untreated wood. The present study examines the performance of three coatings on un...
R Stirling, P I Morris
An Overview of Western Red Cedar as a Wood Pole Species
2014 - IRG/WP 14-10815
This paper reviews the characteristics of western red cedar, with particular emphasis on its use in utility poles. Western red cedar naturally grows primarily in British Columbia, Alaska, Washington, Oregon, California, Idaho and Montana. Compared to other commercial softwoods it has low density, increased corrosivity, weaker mechanical properties, high dimensional stability, and high natural dura...
M H Freeman, R Stirling
Reducing Extractives Stain in Western Red Cedar Sidewall Shingles
2014 - IRG/WP 14-30654
One of the aesthetic challenges that western red cedar shingles face is extractives redistribution stain, particularly in unpainted sidewall applications. Dip and pressure treatments with a mixture of quaternary ammonium compounds and alkyl amine oxides were investigated for their ability to prevent this stain. After nine months of exposure in Vancouver, extractives stain was present on nearly all...
R Stirling
Field Performance of Old-Growth and Second-Growth Western Red Cedar Fence Posts with and without Barrier Wraps
2015 - IRG/WP 15-10838
Many authors have suggested natural durability may be lower in second-growth western redcedar than in old-growth. One potential means of offsetting a decline in durability is use of physical barriers to separate the wood from soil. In the present work we compared the durability of old-growth and second-growth western red cedar posts, with and without barrier wraps, in a field test. After ten year...
P I Morris, J K Ingram, R Stirling
Factors Affecting Performance of Preserved Wood Decking Against Decay Fungi
2015 - IRG/WP 15-30663
Decking is the largest market for residential preserved wood in the United States. Preserved decking must be resistant to colonization by decay fungi initiating from spores, and occasionally from mycelia due to elevated soil levels or adjacent untreated wood. The most vulnerable parts of a preserved wood deck are untreated, or under-treated, wood that becomes exposed by field cuts and checking. Fi...
R Stirling, P I Morris
Global survey on durability variation – on the effect of the reference species
2016 - IRG/WP 16-20573
Climate change due to anthropogenic emissions is the largest environmental challenge of our time. Forest-based value chains play an important role in reducing the accumulation of CO2 in the atmosphere. Maximizing the use of wood to tackle climate change requires improved understanding of the service life of timber products. This information can best be obtained from field testing and while there i...
R Stirling, G Alfredsen, C Brischke, I De Windt, L P Francis, E Frühwald Hansson, M Humar, J Jermer, M Klamer, M Kutnik, P Laks, I Le Bayon, S Metsä-Kortelainen, L Meyer-Veltrup, P I Morris, J Norton, T Singh, J Van Acker, J Van den Bulcke, T M Venås, H Viitanen, A H H Wong
Colorant Treatments to Enhance the Weathering Resistance of Western Red cedar
2016 - IRG/WP 16-40737
Western redcedar is renowned for its decay resistance, but, like most wood products, it requires frequent maintenance in many exterior applications to maintain its appearance. To provide adequate long-term performance in exterior applications, it must be protected against light, water, and disfiguring fungal growth. Colorant treatments, with and without preservatives, were investigated for their a...
R Stirling, V Landry
Field Performance of Refractory Species Treated with MCA
2017 - IRG/WP 17-30706
Micronized copper azole (MCA) has been used extensively over the past decade to preserve southern pine, and other wide sapwood species. Treatment of refractory species is less common, in part due to concerns about treatability and resulting efficacy. To address these concerns, white spruce and Pacific silver fir stakes, and lodgepole pine and red pine posts, were pressure-treated with multiple ret...
R Stirling, J K Ingram, P I Morris
The impact of coatings on the service life of wood decking
2018 - IRG/WP 18-20635
The durability of wood decks depends on the nature of the environment in which they are exposed to, the dimensions and configuration of the components, the resistance of the wood to degrading factors in that environment, and the maintenance performed on the deck. The present work seeks to better understand the performance of selected wood decking systems when maintained and unmaintained. This expe...
R Stirling, D Wong
Identifying the fungal community on western redcedar (Thuja plicata) wood in field tests above and in ground contact exposure: preliminary results
2019 - IRG/WP 19-10939
Western redcedar (Thuja plicata) is a high value species in the Canadian forest industry due in large part to the natural durability of its heartwood. Western redcedar heartwood contains extractives that are inhibitory to the growth of many fungi responsible for decay. In order to gain insights into which extractives are important in long term durability, and which fungi are important to decay of ...
A Dale, S Kus, R Stirling
Performance based specification of wood – Introducing project CLICKdesign
2019 - IRG/WP 19-20661
This paper introduces the new ForestValue research project CLICKdesign – delivering fingertip knowledge to enable service life performance specification of wood. This European consortium is working on the primary innovation to move from the complex, fragmented and general to the easy-to-use, consolidated and specific by provision of an accessible digital tool for specifiers. Competing materials ...
E Suttie, C Brischke, E Frühwald Hansson, S Fortino, J Sandak, M Kutnik, G Alfredsen, C Lucas, R Stirling
Performance of field cut preservatives above-ground and in ground contact exposures
2019 - IRG/WP 19-30742
Field cut preservatives are needed to protect cut ends and drill holes that expose the untreated interior of preserved wood. A series of field cut preservatives were assessed in ground contact and above-ground exposures. After 10 years in ground contact exposure, all of the untreated controls had failed or exhibited very advanced decay. In contrast, the copper naphthenate (2% Cu in mineral spirits...
R Stirling, D Wong
Performance of naturally durable decks after 15 years of field exposure
2020 - IRG/WP 20-10963
A decking test of Canadian species considered to be naturally durable was inspected after 15 years of exposure at test sites in Ontario and British Columbia. Based on the materials used in this experiment, Douglas-fir and yellow cypress had the greatest decay resistance, followed by eastern white cedar and western redcedar, and then by western larch and tamarack. All materials tested were more dur...
R Stirling, D Wong
Above-Ground Termite Resistance of Naturally Durable Species in Ontario and Mississippi
2022 - IRG/WP 22-30767
A collaborative above-ground protected termite field test was initiated by FPInnovations and the USDA Forest Service at sites in Ontario and Mississippi. The aims of the experiment were to compare the rate of attack in protected, above-ground exposures by the subterranean termite species, Reticulitermes flavipes, between northern (Ontario) and southern (Mississippi) test sites and to generate perf...
R Stirling, M Mankowski
Challenges in managing very long-term field tests
2023 - IRG/WP 23-30779
Field testing of wood preservatives has been on-going in Petawawa, Ontario, Canada since at least 1937. Many of the treated roundwood posts from these early experiments are still in test, and include preservatives still used today, including creosote, copper naphthenate, pentachlorophenol and CCA. Performance data from selected experiments more than 50 years old are reported and we discuss some of...
R Stirling, D Wong