Your search resulted in 366 documents. Displaying 25 entries per page.
Effect of post-treatment processing on leachability of ACZA-treated douglas-fir lumber
1998 - IRG/WP 98-50109
The effect of post-treatment procedures that more rapidly precipitate copper, zinc, and arsenic in douglas-fir treated with ammoniacal copper zinc arsenate (ACZA) on subsequent leaching resistance were investigated at two retentions (6.4 and 40 kg/m3). Total leaching was greater from boards treated to the higher retention. At both levels, copper was lost at the highest rate. Post-treatment process...
J J Morrell, C S Love, S Kumar, C M Freitag
Internal pressure development in Douglas fir lumber during pressure treatment
1997 - IRG/WP 97-40091
Preservative treatment of Douglas fir lumber to meet current industry standards poses a major challenge and a variety of methods have been developed to overcome these problems. One aspect for treatment improvement that has received less attention is the relative effect of treatment parameters on changes in pressure within the wood. Previous studies of spruce and radiata pine suggest that internal ...
P F Schneider, J J Morrell
Movement of chloropicrin, Vapam, and methylisothiocyanate in southern pine and Douglas fir timbers
1987 - IRG/WP 3410
Douglas fir and southern pine timbers, 15.2 x 15.2 x 426 cm³ (6-in x 6-in x 14-ft), were "inoculated" with brown-rot and white-rot fungi as vapor-sensing agents to evaluate the movement and distribution of fungitoxic concentrations of chloropicrin, Vapam, and methylisothiocyanate (MIT) over a 20-week period. Residual fumigant in timbers was determined by a bioassay with Gloeophyllum trabeum. The ...
T L Highley
Effect of humidity and temperature on fastener withdrawal resistance from CCA and ACZA treated Douglas-fir
2000 - IRG/WP 00-20209
The effects of preservative treatment on fastener withdrawal was investigated in Douglas-fir lumber conditioned to two moisture regimes. In general, conditioning samples to 19% moisture content produced more substantial changes in withdrawal resistance of galvanized fasteners than did conditioning to 12%. Treatment had little or no effect on withdrawal resistance of stainless steel fasteners. With...
Sung-Mo Kang, J J Morrell
Fixation and leaching characteristics of Douglas-fir treated with CCA-C
2004 - IRG/WP 04-50213
Fixation and leaching characteristics of CCA-treated Douglas-fir was evaluated using the expressate method and the AWPA E11-97 leaching procedure. CCA fixation, as monitored by the chromium reduction, was much faster in heartwood than in sapwood; however, copper and arsenic fixation in heartwood appeared to be incomplete regardless of the extension of fixation time. This poor fixation of copper a...
Gyu-Hyeok Kim, Yun-Sang Song, Dong-heub Lee
Performance of Preservative Treated Parallel Strand Lumber in Marine Exposures.
2006 - IRG/WP 06-30407
The performance ACZA treated Douglas-fir and CCA southern pine parallel strand lumber (PSL) was studied in marine exposures in Florida or Oregon. While materials treated to retentions below the recommended levels for marine exposure were attacked in Oregon, properly treated panels of either species performed well. Panels treated with these same chemicals and exposed in Florida experienced attack ...
J J Morrell, C S Love, P Merrick
Effect of fungal attack on maximum load capacity of simulated wall assemblies
2007 - IRG/WP 07-20363
The effects of moisture intrusion and fungal attack on the maximum load capacity of nailed assemblies was investigated using one white and one brown rot fungus against 4 material combinations over a 20 week period. Wetting significantly reduced the maximum load capacity of all four material combinations, while wetting and autoclaving only affected the OSB sheathing/spruce stud. The white rot fung...
N Melencion, J J Morrell
The effect of wood moisture content and rod dosage on movement of boron through Douglas-fir heartwood
2007 - IRG/WP 07-30431
The potential for moisture sorption by boron rods following application to wood to affect subsequent boron diffusion was investigated in small Douglas-fir blocks conditioned to 30, 60 or 90% moisture content (MC). MCs tended to decline over the 180 day test period, but there was no evidence that the rods acted to draw moisture away from the wood. As expected, boron movement tended to increase with...
Y Cabrera, J J Morrell
Comparative study between full cell and passive impregnation method of wood preservation for laser incised Douglas-fir lumber
2007 - IRG/WP 07-40359
Many wood species are highly resistant to conventional pressure treatment. To improve the chemical impregnation into Douglas-fir (Pseudotsuga menziesii Franco) lumber, the passive impregnation method had been developed. In this study, ability of the passive impregnation for lumber was compared with a conventional full cell method. Square Douglas-fir lumber with the incising density of 10,000 holes...
Md N Islam, K Ando, H Yamauchi, Y Kobayashi, N Hattori
A comparison of rates of decay and loss in stiffness of radiata pine and Douglas fir framing lumber
2008 - IRG/WP 08-20378
Stiffness loss with time was recorded for untreated radiata pine and Douglas fir framing size lumber and preservative treated radiata pine which dad been pre-inoculated with Oligoporus placenta, a brown rot decay fungus isolated from decaying untreated radiata pine framing. Between stiffness measurements, samples were contained in a plastic tank located outside at ambient temperature. Index of Con...
M Hedley, D Page, J van der Waals
Field Tests of naturally Durable North American Wood Species
2008 - IRG/WP 08-10675
There has been little field test performance data published on North American naturally durable species in general, and no published data on second growth material in particular. Yellow cedar (Callitropsis nootkatensis), western red cedar (Thuja plicata), eastern white cedar (Thuja occidentalis), and three wood species reputed to be moderately durable were installed in ground-contact (stakes) an...
P E Laks, P I Morris, G M Larkin, J K Ingram
Effect of a biological treatment on below ground decay of Douglas-fir pole sections
2008 - IRG/WP 08-40433
The use of exogenous sugars to accelerate microbial growth and eventually limit available oxygen in soil surrounding wood in soil contact was investigated on untreated Douglas-fir poles exposed over a 3 year period in Western Oregon. Isolation frequencies differed markedly between treated and untreated poles and the treatment did appear to shift the frequency of some basidiomycetes. The treatment ...
C Freitag and J J Morrell
Use of Internal Remedial Treatment to Extend Wood Life at the Fort Vancouver National Historic Site
2010 - IRG/WP 10-30525
The condition of wood in a reconstructed fur trading fort was assessed over a 30 year period. Poor initial treatment had resulted in the development of extensive early decay. While supplemental treatment with chloropicrin and methylisothiocyanate had arrested the attack, the results suggested that remedial treatments were unable to completely overcome the initial problems associated with treatmen...
C S Love, C Freitag, J J Morrell
Investigating extraction of bifenthrin from composite wood products
2011 - IRG/WP 11-20467
Bifenthrin is added to resin prior to lay-up of plywood and laminated veneer lumber to provide termite protection. Analysis of this chemical in resins can be challenging. The potential for using ground wood in place of sawn material to recover bifenthrin was investigated using laminated veneer lumber composed of Douglas-fir veneers analyzed by three laboratories. Although the results differed amo...
J J Morrell, L Bell, J Norton, C Shaw
Performances of Douglas fir in real outdoor use conditions
2011 - IRG/WP 11-20472
The European standard EN 350-2 classifies Douglas fir as moderately resistant to fungal decay on the basis of standardized laboratory and field tests. However, the lifespan expectancy of outdoor structures such as cladding, decking and elements of wood construction carpentry may also vary according to environmental conditions (climate, exposure to weathering), maintenance and design. An investigat...
M Kutnik, S Lepetit, S Le Nevé
Effect of growth rate and radial position on the natural durability of Douglas-fir
2012 - IRG/WP 12-10791
In terms of natural durability, Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) fame owns to the favourable characteristics of centuries-old trees harvested in old-growth North American forests. The properties of wood coming from plantations harvested between 50 and 100 years-old are likely to be different. In such stands, plantation density and thinning intensity may have a large impact on the...
C Pollet, J-M Henin, B Jourez, J Hébert
Potential for using boron for mitigation of Phytophthora ramorum in Douglas-fir logs
2014 - IRG/WP 14-30643
Phytophthora ramorum is a relatively newly described pathogen present in the forests of Northern California and southwest Oregon in the United States. This organism has an extremely wide host range, including a number of commercial important conifers, among them Douglas-fir (Pseudotsuga menziesii). The continuing expansion of the range of P. ramorum will result in an increasing quarantine area w...
J M Hulbert, J J Morrell E M Hansen
Effects of thermal modification on properties of Douglas-fir heartwood
2014 - IRG/WP 14-40663
The flexural properties and mass losses of thermal modified Douglas-fir pretreated with boron or glycerol were examined. Pretreatments were associated with slight, but not significant, reductions in modulus of rupture (MOR) and modulus of elasticity （MOE）of Douglas-fir at different thermal treatment levels. Boron pretreatment had the greatest effect on MOR. MOR of non-pretreated and ...
Li Yan, J J Morrell
Effect of polyurea coatings on performance of Douglas-fir in tropical above ground exposures
2014 - IRG/WP 14-40665
The potential for using polyurea barriers to limit fungal and termite attack was investigated on Douglas-fir lumber and timbers. Termites were capable of penetrating the barrier to attack non-treated wood as well as wood dip-treated with disodium octaborate. The coatings were also exposed above ground for 48 months in Hilo Hawaii. Samples were dissected to detect internal decay. Coated non-trea...
S Uysal, J J Morrell
Douglas-fir PSL Treated with Oilborne Copper Naphthenate – Treatment Experience & Efficacy
2014 - IRG/WP 14-40687
Treating characteristics, field stake efficacy and the results from treatment trials for oilborne copper naphthenate (CuNap) and Douglas-fir parallel strand lumber (PSL) are summarized in this paper. Treatment with a P9 Type-C based solution in laboratory tests showed full cross section penetration of large cross sections could be achieved. Commercial treatment trials using a P9 Type-A solution ...
G P Merrick
Buffered Amine Oxide Treatment Systems for Imparting Water Based Azoles/Insecticides in Douglas Fir and Eucalyptus
2015 - IRG/WP 15-40707
In today’s world, wood remains the most versatile, practical and sustainable building material. In contemporary countries, wood is a well-managed renewable resource that has a remarkably small carbon footprint compared to those of steel, aluminium, composites, and concrete. These alternative materials have continued to emerge as viable building materials given the durability issues of untreate...
R W Clawson Jr
A Treatability Study of Western Wood Species with Water Based Azoles and Insecticides Using Buffered Amine Oxides
2016 - IRG/WP 16-40766
The use of Western U.S. Wood Species remains small in today’s global wood product market when compared to the use of other commercially available softwoods. One reason that other fiber sources, those that may be less naturally durable or exhibit slightly inferior mechanical properties, are utilized is ease of treatment. In an attempt to ensure adequate penetration in commercially important an...
R W Clawson Jr, C N Cheeks, K A Cutler
Dynamics of biofilm formation on wood impregnated with vegetable oils
2016 - IRG/WP 16-40769
Biofilms can be used as a living protective coating for wood, showing advantages compared to traditional wood-coatings regarding sustainability and self-repair. Biofilms can be formed on oil impregnated wood. Such an oil-biofilm system has the potential of protecting the wood against UV and bio degradation, creating a homogeneously black surface with self-healing properties. Results of biofilm for...
K Filippovych, H Huinink, L van der Ven, O C G Adan
Case study: “Riesenbühlturm”
2017 - IRG/WP 17-20599
In this case study four 7 m long Douglas fir crossbeams were investigated regarding the remaining metal and moisture content. The crossbeams were replaced from a timber tower after 10 years of service in the Black Forest region (South Germany) due to fungal decay. From each of the crossbeams five stem discs were taken and relevant parameters (density, moisture and remaining metal content) were de...
E Melcher, J Müller
Monitoring Diversity and Colonization Patterns of Wood-Inhabiting Fungi Using Field Stake Tests
2017 - IRG/WP 17-20614
Advances in molecular identification of microbial communities enabling rapid microorganism determination have allowed ecological data to be increasingly incorporated into standardized wood performance tests. Combining standard field tests with molecular methods to study wood-associated microflora can help to better understand fungal colonization and decay processes of wood in service. The potentia...
P Torres-Andrade, J Cappellazzi, J J Morrell