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Anti-stain field trials in British Columbia
1981 - IRG/WP 3174
Four alternative anti-sap stain chemicals were subjected to a four month field evaluation during the summer of 1980. The test, established at a Vancouver Island sawmill, was designed to evaluate the potential long-term effectiveness of sodium tribromophenate (Velsicol Ltd.), Biocom XX (Bramco Industries) containing methylene bis-thiocyanate, Woodbrite NTX (Van Waters & Rogers Ltd.) containing 3-iodo-2-propynyl-butyl carbamate and Mitrol 48 (Kenogard) containing guazatine acetate and quaternary ammonium chlorides, on hemfir and Douglas fir. Sodium tribromophenate was found to give surface protection equivalent to that of chlorophenate treated controls. Biocom XX was also effective, although the active ingredient came out of solution at the required treating solution concentration. Woodbrite NTX and Mitrol 48 were found to be ineffective on either species group under the test conditions.
D V Plackett


Forest management policies and timber supplies in British Columbia
1997 - IRG/WP 97-10244
British Columbia has a huge wealth of timber resources, currently exceeding 7 billion m3 of mature timber on about 43 million ha classified as productive forest lands. That land area also supports a current volume of over 2 billion m3 of timber in immature stands. How much of the volume will be made available as an annual timber supply for the forest industry is dependent upon a set of policies governing timber harvest regulation, including social decisions on land and resource allocations, such as parks, and required resource management practices, such as environmental protection measures. These policies are considered by the province's Chief Forester along with detailed inventory data when determining an Allowable Annual Cut for each sustained-yield management unit. This paper provides an overview of timber harvest regulation in British Columbia and examines some of the major policy initiatives affecting timber supplies. Results of the recent Timber Supply Review are presented, along with a forecast of timber supply trends over the next several decades. Opportunities for increasing future supplies are identified.
R B Addison


Information regarding a report on the "Code of Good Practice" for the use of chlorophenoxides for wood preservation
1984 - IRG/WP 3302
In 1981 the British Columbia Chlorophenate Wood Protection Task Force was formed to respond to workers' health and environmental concerns regarding the use of chlorophenoxides for control of sapstain and mould fungi at sawmills and lumber export terminals. The task force consisted of representatives of both the federal government (Environment Canada) and the provincial government (British Columbia), the B.C. forest industry and labour unions. After two years of deliberations the task force has produced a document "Code of Good Practice" for the design and operation of wood protection facilities. This code provides recommendations for workers' health and safety and for the storage, transportation and disposal of chlorophenoxide liquids and contaminated water and solid wastes. The code details in ten sections such aspects as the need for wood protection; chlorophenols and chlorophenoxides - physical and chemical properties, toxicity, human health effects; personnel protection; general practices at wood protection facilities; recommended design features; recommended operating practices; transportation of chlorophenoxide-containing materials; disposal of wastes; spill contingency planning and a summary of the Canadian legislation on the topic.
V N P Mathur


Scientific development for prolonging the service life of timbers by impregnating with creosote or organic solvent type preservatives in which additive has been incorporated
1977 - IRG/WP 382
Chemically impregnated wood has played a prominent part in the Telephone and Electricity Distribution Industry during the past century and there is no doubt that it will play an equally prominent part in the future. The reasons why wood poles and wooden, structures predominate, are that when adequately chemically impregnated with a recognised timber preservative to ensure the expected service life for the purpose envisaged, the timber is then fully protected against the ravages of wood destructive organisms. Furthermore, wood is endowed with many natural characteristics that make it a favourite pole and structural material. Its high strength, light weight, ability to absorb impact or shock from loads suddenly applied and ability to resist overloading for brief periods plus its well-known insulating qualities - all are important basic reasons for its predominance in pole line structure. The use of chemically impregnated timber often makes it possible to carry out a given construction programme at less cost, or to erect more structures for a given sum of money, than when more expensive construction materials are employed.
P R B D De Bruin


A survey to assess the current and future usage of timber in British port structures
1998 - IRG/WP 98-10247
Port engineers responsible for 30 British ports were surveyed by questionnaire or interview to establish current and prospective usage of timber in those ports. The ports surveyed account for about 25% of total cargo handled annually in Britain and being located all around the British mainland, were considered to form a representative sample. The survey identified the hardwoods and softwoods in use for various applications in port structures, the criteria for selecting materials for these structures, the materials considered most suitable for piles and fenders and the types of preservative specified. Additional data was collected on the current condition of structures, incidence of marine borers, experience and training of port engineers and their attitude towards timber.
G S Sawyer, S E M Plaster


Variation in natural durability of British grown Douglas fir ((Pseudotsuga menziesii (Mirb.) Franco). Part I. Effect of density and growth rate
2002 - IRG/WP 02-10445
Seed origin trials of Douglas fir (Pseudotsuga menziesii) in Britain have provided important information on growth differences between origins (Lines, 1987), but the variation in wood properties between origins has not been reported. The present paper describes a study of the variation in natural durability against two brown rot fungi (Coniophora puteana and Postia (Poria) placenta) and in a fungal cellar test between four seed origins of Douglas fir. In addition to natural durability, tree diameter, heart-, sap- and total cross-sectional areas, density, bending properties, extractive content and composition were determined to examine their effect on natural durability. The effects of extractive content and composition on durability are discussed in a second paper (Part II: Effect of extractive content and composition). The proportion of the total variation in natural durability explained by differences between seed origins and differences between trees within origins were estimated to indicate the potential of tree breeding programmes for modifying this wood property. (Poria) placenta) and in a fungal cellar test between four seed origins of Douglas fir. In addition to natural durability, tree diameter, heart-, sap- and total cross-sectional areas, density, bending properties, extractive content and composition were determined to examine their effect on natural durability. The effects of extractive content and composition on durability are discussed in a second paper (Part II: Effect of extractive content and composition).
S Akhter, M D C Hale


Variation in natural durability of British grown Douglas fir ((Pseudotsuga menziesii (Mirb.) Franco). Part II. Effect of extractive contents and taxifolin
2002 - IRG/WP 02-10446
The previous paper (Part I: Effect of density and growth rate) described the variation in natural durability of 4 Douglas fir (DF) seed origins (Darrington, J. Landing, Naselle and Hawkinsville) in a pure culture decay test and fungal cellar test. The pure culture tests were performed against two brown rot fungi (Coniophora puteana and Postia placenta). In the fungal cellar test soft rot was the predominant decay type because of the high moisture content. The paper showed that significant variation in natural durability occurred between the seed origins and between trees within the seed origins. Furthermore density partly explained the variation in the natural durability of 3, of the 4 seed origins. Extractives are often considered to be the major reason for heartwood durability. This paper has determined the variation in extractive contents between different seed origins and has examined the effect of extractive contents and taxifolin, the main component of acetone extracts on the decay resistance of 26 year old DF trees from different seed origins.
S Akhter, M D C Hale