Your search resulted in 581 documents. Displaying 25 entries per page.
Assessment of untreated Papua New Guinea timbers against subterranean termites. Final report
1993 - IRG/WP 93-10041
Four years after the exposure of eight timber species of varying density against subterranean termites in a field trial, Kwila was still generally sound while Taun, Malas and PNG Walnut were beginning to be attacked slightly to moderately. Calophyllum, Kamarere, PNG Beech and White Cheesewood were severely attacked and failed. Results after the period of exposure shows that Kwila rates highly as t...
H C Konabe, M Rokova
Non leachability of arsenic, copper and chromium from 15 years old CCA-C treated southern pine poles used in brackish water as jetty piles in Bangladesh
1998 - IRG/WP 98-50103
Revealed that chromated copper arsenate type C (CCA-C) treated southern pine poles used in Central Warehouse Jetty of REB, Khulna are stable and resistant to chemical and biological attack without loss of any component from outer 0-12.5 mm zone after 15y of use. Slightly reduced retention (4.44% less) was noted in above water location of piles (bottom end of tree) which would be due to continuous ...
A K Lahiry
Field and greenhouse testing of window joinery of pine and spruce treated with LOSP
1991 - IRG/WP 3658
Norwegian window frame components of full size were double vacuum-treated with TBTN and TBTO, and connected as 'L-joints' and subsequently coated with stains. The corner sections were exposed (out of ground contact) both in field (temperated coastal climate, Taastrup, Denmark) and in a greenhouse (Uppsala, Sweden). The window frame L-joints of spruce (Picea abies Karst.) - treate...
F G Evans, B Henningsson, E Borsholt
Models of the critical time of humidity and temperature conditions for the development of mould fungi in pine and spruce sapwood
1995 - IRG/WP 95-20066
Regression models of the time factor for the growth of mould fungi in pine and spruce sapwood are studied. The first group of models are based on the results of exposures of mould fungi in static humidity and temperature conditions indicating the time for the start of mould growth in wood. The second group of models are based on the exposures of mould fungi in fluctuating or alternating humidity a...
H Viitanen
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
Micromorphology of Schizophyllum commune attack in pine (Pinus sylvestris) wood
1983 - IRG/WP 1184
The decay pattern caused by Schizophyllum commune in pine latewood tracheids was studied using both light and transmission electron microscopy. The attack began as isolated concentric slits within the S2 layer with extensive lamellation and separation of individual wall layers observed in subsequent stages of decay. The slits resulting from attack appeared to be formed in thin, regular concentric ...
T Nilsson, G F Daniel
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
Water-Borne Copper Naphthenate: An Emerging Wood Preservative
2002 - IRG/WP 02-30280
Waterborne copper naphthenate (WB Cu-N) was used to treat southern yellow pine (Pinus spp) and red maple (Acer rubrum) stakes. The treated stakes were exposed in test sites located in Florida, Michigan and Mississippi for 3 to 6 years. Copper Chromium Arsenate (CCA),
Ammoniacal Copper Quat (ACQ) and Oil-borne Copper Naphthenate (OB Cu-N) were also used to treat some stakes for comparison. Results...
P Nzokou, D P Kamdem, M H Freeman
Durability of heat-treated wood
1999 - IRG/WP 99-40145
Heat-treated wood from the French process were laboratory tested against decay using agar block test and a modified soil block test. Water absorption, bending strength, lignin content and acid number were also determined to evaluate the effect of heat treatment. Heat treated samples exhibit a higher lignin content and a lower acid number compared to untreated control indicating the degradation of ...
D P Kamdem, A Pizzi, R Guyonnet, A Jermannaud
Leachability of didecyldimethylammonium chloride (a quaternary ammonium compound) from four wood species
1982 - IRG/WP 3204
Sapwood blocks prepared from red pine, ponderosa pine, southern yellow pine and hem-fir (a commercial mixture of western hemlock and amabilis fir) were treated with didecyldimethylammonium chloride, (an alkylammonium compound, AAC). After oven drying the blocks were vacuum impregnated with distilled water and subjected to a static leach cycle for 48 hours. The leachate was analyzed and the amount ...
J N R Ruddick, A R H Sam
Supercritical fluid impregnation of Douglas-fir heartwood with cyproconazole using temperature induced deposition
2003 - IRG/WP 03-40259
A limited understanding of the fundamental aspects of supercritical fluid (SCF) impregnation in wood remains an obstacle to the development of this technology. Developing a better understanding of the effects of various process parameters on treatment results would facilitate more rational development of SCF impregnation. In this project, the effect of treating period and specimen length on su...
Sung-Mo Kang, J J Morrell
Supercritical fluid treatment: Effects on bending strength of white spruce heartwood
1993 - IRG/WP 93-20008
The effects of supercritical carbon dioxide on wood strength were evaluated using white spruce heartwood, a species known to be especially susceptible to collapse during exposure to higher pressures. The effects of pressures of 2000 or 3600 psig and temperatures of 40 or 80°C were evaluated using 30 or 60 minute exposure periods. No significant differences were noted in modulus of rupture or modu...
S M Smith, J J Morrell, E Sahle-Demessie, K L Levien
Natural durability transfer from sawmill residues of white cypress (Callitris glaucophylla). - Part 1: Optimisation of the extraction conditions
2000 - IRG/WP 00-30238
As the first phase of a large project aimed at recovering 'waste' durability components from sawmill residues of Callitris glaucophylla, several solvents and extraction methods were evaluated, initially in the laboratory and then at pilot industrial scale. Extracts were compared by crude total dissolved solids content, by chemical analysis using GC-MS and LC-MS, and by laboratory...
M J Kennedy, Hui Jiang, L M Stephens
Effect of climate, species, preservative concentration and water repellent on leaching from CCA-treated lumber exposed above ground
2001 - IRG/WP 01-50178
Few studies have examined leaching of chromated copper arsenate (CCA) from treated wood in above ground exposures due to the assumption that leaching is less severe compared to wood in continuous contact with soil or water. However, a significant portion of CCA treated wood is used for above ground applications, exposing considerable volumes of the preservative to precipitation and potential leach...
J L Taylor, P A Cooper
Assessing the leachability of chlorothalonil and methylene bis thiocyanate from antisapstain treated radiata pine
1998 - IRG/WP 98-30176
Rain wash-off and leaching of antisapstain fungicides from wood may cause pollution of waterways and may also lead to a decrease in the efficacy of a formulation against fungal degrade as chemicals deplete from the timber surface.
In the current study, the leachability of chlorothalonil (CTL) and methylene bis thiocyanate (MBT), the active ingredients of a commercial antisapstain formulation, was...
B Kreber, T L Woods
Field evaluation of the above-ground susceptibility of Pinus heartwood and untreated or treated sapwood to two species of Australian subterranean termites
1996 - IRG/WP 96-10147
Plantation-grown Pinus elliottii, Pinus caribaea and Pinus radiata specimens containing heartwood and untreated or preservative-treated sapwood were exposed above ground to the subterranean termites Coptotermes acinaciformis or Mastotermes darwiniensis near Sydney (NSW), Brisbane and Townsville (Qld), and Darwin (NT), using a variety of exposure techniques. Heartwood of Pinus elliottii and Pinus c...
M J Kennedy, J W Creffield, R H Eldridge, B C Peters
Use of mixed populations of microflora to control sapstain on radiata pine
2002 - IRG/WP 02-10427
Most methods of biological control in the wood products field have focused on the use of single species of fungi or bacteria to control sapstain or decay. The approach taken in this study involved applying soil microorganisms, in combination with nutrients and various adjuvants that collectively form the biological control system.
Radiata pine branch discs, autoclaved or fresh, were dipped in ...
C Chittenden, R Wakeling, B Kreber
Laboratory studies on control of sapstain and mold on unseasoned wood by bacteria
1991 - IRG/WP 1493
A malt-agar and nonagar laboratory test was used to evaluate the efficacy of bacterial preparations as biological control agents against several sapwood-inhabiting fungi. Both nonsterilized and filter sterilized bacteria preparations prevented attack by the sapwood-inhabiting fungi. Streptomyces rimosus was the most effective bacteria, giving good protection, with a 1-hr soak in a filter-sterilize...
T L Highley, R Benko, S C Croan
An optimum schedule for treating radiata pine
1998 - IRG/WP 98-40105
New Zealand grown radiata pine was treated with copper chrome arsenate preservative using Bethell process. Four different treatment schedules were tried. Keeping the duration of pressure stage constant (either 15 minutes or 45 minutes) and increasing the duration of vacuum (from 15 minutes to 30 minutes) or keeping the duration of vacuum stage constant (either 15 minutes or 30 minutes) and increas...
R Gnanaharan, D R Page
Improvement of intrinsic properties of wood by chemical wood densification - Hydrophobic aspects and durability aspects
1999 - IRG/WP 99-40149
To improve the intrinsic properties of Scot pine wood ((1) hydrophobic surface and (2) durability), two ways of chemical modification have been tested. The first one is the chemical modification of hydroxyl groups by active substances like diisocyanate compounds with a copolymerization step. The second way is a densification by an impregnation of resins and a gamma polymerisation. This second way ...
G Labat, Q K Tran, I Le Bayon
Water repellency of wood treated with alkylammonium compounds and chromated copper arsenate
2000 - IRG/WP 00-30231
The comparative water sorption properties of southern pine treated with CCA and several alkylammonium compounds was evaluated for freshly treated wood and for wood after exposure in a fungus cellar. It was found that CCA imparts considerable water repellency to wood which is reduced somewhat after exposure to wet soil. With the exception of a long chain (C20 -C22) compound, the alkylammonium compo...
D D Nicholas, A Kabir, A D Williams, A F Preston
Comparative field performance of CCA and CCA-water repellent treated Southern pine lumber
1995 - IRG/WP 95-30089
This paper describes the field performance of end-matched southern pine boards treated with either CCA type C or CCA type C containing an emulsion water repellent (WR) additive. Boards were either kiln or air-dried after treatment, constructed into decks, and exposed for over 3 years at Harrisburg, NC. During this exposure, matched boards were monitored for internal moisture content, cupping at mi...
A R Zahora
Leaching of preservative components from pine decking treated with CCA and copper azole, and interactions of leachates with soils
2001 - IRG/WP 01-50171
Radiata pine decking was treated with CCA and copper azole preservatives to Australian H3 retention using conventional and modified Bethel schedules, and air-dried. Treated decking boards and durable hardwood controls were subjected to leaching in weather-exposed decks, and matching 19mm cubes were leached in extended AWPA E11-97 lab tests. Deck runoff and E11 leachate water was analysed after rai...
M J Kennedy, P A Collins
Sampling and analysis of NeXgen-treated timber
1998 - IRG/WP 98-20134
Green sawn timber surfaces of the softwood Caribbean pine and the hardwood white cheesewood were treated by dipping, spraying, and precise spiking with the antisapstain product NeXgen. After storing for either two hours or two weeks, the treated surfaces were sampled by one of four alternative protocols, which included two involving a square wad sampling punch (one hit or six hits), one involving ...
M J Kennedy, D E Ferlazzo, T L Woods, M H Freeman
Tunnelling bacteria
1983 - IRG/WP 1186
The micromorphology of decay in wood caused by a certain group of single-cell bacteria, called tunnelling bacteria (TB), is described. TB are characterised by their tunnelling ability within the secondary cell walls of wood fibres. Pure cultures of TB have not yet been obtained although the typical decay patterns can be reproduced using mixed bacterial cultures. Some indications of lignin degradin...
T Nilsson, G F Daniel