Your search resulted in 109 documents. Displaying 25 entries per page.
Ponding of radiata pine (Pinus radiata) - 2. The effect of ponding on coating penetration into wood
1998 - IRG/WP 98-10249
Radiata pine (Pinus radiata) wood panels which had been ponded for periods ranging from 2 to 12 weeks, dried and subsequently coated with a primer and examined by light microscopy after staining sections with Sudan IV to enhance the contrast of the primer material.
A correlation between the extent of ponding and the extent of coating penetration into wood was observed. The coating penetration var...
A P Singh, S S Gallagher, U Schmitt, B S Dawson, Yoon Soo Kim
Bacterial degradation of Pinus radiata compression wood
1996 - IRG/WP 96-10153
An inspection of twelve year old, CCA-treated Pinus radiata wood from an industrial cooling tower showed extensive surface decay of wood. Electron microscopic examination of decaying compression wood indicated that compression wood cells were attacked exclusively by bacteria, which were of erosion and tunnelling types. As compared to the normal wood, compression wood appeared to be more resistance...
A P Singh, R N Wakeling
The use of selective media for studying the colonization of wood in ground contact by microorganisms
1978 - IRG/WP 186
In October1976 a field trial was set up in order to monitor the progressive colonisation of wood in ground contact using orientated small stakes of Scots pine (Pinus sylvestris) and birch (Betula sp.) (30 x 45 x 250 mm³). Half the number of each species were treated with a 1% solution of CCA by a vacuum impregnation process. All the stakes were coated on three sides with an epoxy-resin sealant to...
C P Clubbe
Ultrastructure of Prumnopitys ferruginea wood from a buried forest in New Zealand
1991 - IRG/WP 1489
The buried wood of Prumnopitys ferruginea, a New Zealand native tree, was examined by scanning and transmission electron microscopy to investigate the extent to which the wood had deteriorated and the cause of its deterioration. Examinations showed that some deterioration of wood had occurred. Microscopy revealed a decay pattern similar to that produced by cavitation bacteria. Lenticular cavities ...
A P Singh, T Nilsson, G F Daniel
16S rRNA Analysis of the Bacteria Associated with Biocide Degradation
2004 - IRG/WP 04-10543
The bacterially mediated degradation of the new anti-fungal biocide, bethoxazin, was studied in vitro, by means of 16S rRNA PCR-amplification and cloning techniques. Woodblocks impregnated with a subtoxic concentration of bethoxazin were incubated in compost, and the micro-organisms associated with the wood after 6 and 12 weeks was studied. It was found that after 6 weeks the wood contained a la...
D F Wallace, D J Dickinson
Wood structure in relation to excessive absorption - a literature survey
1971 - IRG/WP 300
This literature study, composed in connection with 'the structure of wood in relation to the excessive absorption', started from the idea that the subject only could be dealt with successfully if the structure was taken into account in relation to a normal absorption pattern in so far as this knowledge can enlighten the understanding of the abnormal situation. The normal penetrat...
S M Jutte
Assessment of the effects of rentex remedial treatment on some wood pole inhabitant micro-organisms
1994 - IRG/WP 94-30053
The effects of a remedial ground-line treatment using Rentex, a stabilised paste containing a mixture of fluoride and dichromate salts, on the micro-organisms inhabiting a sample of some 160 creosoted, on-line, electricity distribution poles, have been investigated as part of an appraisal of the efficacy of this remedial treatment. Half of the poles were treated and the other half used as controls...
D C R Sinclair, G M Smith, A Bruce, H J Staines
Method of embedding and staining of wood after biological testing to support the identification of decay type
1998 - IRG/WP 98-20131
A method for preparing wood for microscopic analysis after decay testing is described, with special regard to a novel fast simultaneous staining, which helps to identify different types of decay. The novel staining process is explained as well as the embedding of heavily decayed samples in polyethylene glycol (PEG) and picking up of sections by transparent adhesive tape. Special feature of the int...
A O Rapp
Occurrence and importance of various types of fungal and bacterial decay in CCA-treated horticultural pine posts in New Zealand
1984 - IRG/WP 1234
A detailed microscopical examination has been carried out on samples taken from CCA-treated pine posts exposed in horticultural soils. The following decay types were observed: white rot, brown rot, soft rot, tunnelling bacteria, cavitation bacteria, and bacterial erosion. The occurrence and importance of the various decay types between different regions, and plots within a specific region, varied ...
T Nilsson
The effect of concrete embedment on CCA treated hardwood and softwood timbers
1985 - IRG/WP 3340
Small size stakes of Eucalyptus maculata and Pinus elliottii were treated with CCA to various retentions and embedded in concrete collars containing varying amounts of a fungicide additive. During the 30 month trial period stakes were removed after 12, 18, 24 and 30 months and assessed for residual strength. Stakes which showed significant strength reductions were microscopically examined for the ...
L E Leightley, G A Willoughby
Screening of bacteria, yeasts and Trichoderma isolates for antagonism toward stain and mould fungi on agar media and wood
1999 - IRG/WP 99-20159
A screening programme of soil bacteria for antagonism toward mould and wood stain fungi was undertaken on 8 types of agar-based media by application of several bacteria to each plate. The rapid screening method was subsequently verified by testing antagonism of the most promising bacteria on Scots pine sapwood. Most of the 64 bacterial showed antagonistic effects on certain media against individua...
C Payne, A Bruce
Enhanced removal of CCA from treated wood by Bacillus licheniformis in continuous culture
1997 - IRG/WP 97-50083
A gram positive, spore-forming bacterium, which was isolated from a 20-year-old Forest Service test plot of CCA-treated 2 x 4's in Madison, WI., demonstrated the ability to release copper, chromium, and arsenic from CCA-treated wood in liquid culture. CCA-treated sawdust was exposed to this organism, which has been presumptively identified as Bacillus licheniformis. Analysis of the sawdus...
C A Clausen
Cavitation bacteria
1984 - IRG/WP 1235
A form of bacterial wood degradation is described. The term "cavitation bacteria" has been coined in order to describe the discrete cavities that are formed within the wood cell walls. The bacteria observed within the cavities appeared to be polymorphic with rounded as well as filamentous forms recognised. TEM studies suggest that the bacteria produce diffusable wood-degrading enzymes. Cavitation ...
T Nilsson, A P Singh
The association of bacteria with the increased permeability of water-stored spruce wood
1973 - IRG/WP 325
A microbiological investigation was undertaken to check our earlier work on patterns of bacterial counts and pH changes in water-stored wood. A survey of industrial activity was conducted upstream from the storage site with a view to explaining the existing bacterial flora. Further experiments were carried out with spruce bolts in enclosed tanks, using lake water with its natural bacterial flora a...
J A Dunleavy, J P Moroney, S E Rossell
Exposure of preservative treated wood to terrestrial microcosms, pure cultures of fungi and in the field
1997 - IRG/WP 97-20114
Small stakes (5x10x100 mm3) of treated and untreated Pinus sylvestris sapwood were exposed in terrestrial microcosms with different soils, two taken from test fields in Sweden, one soil from a conifer forest and one garden compost soil. Stakes of the same size were also exposed to pure cultures of the brown and white rot fungi, Postia placenta and Phanerochaete chrysosporium. After exposure, weigh...
M-L Edlund
Bacterial degradation of wood cell wall: A review of degradation patterns
1990 - IRG/WP 1460
Information from bacterial degradation studies of 60's and 70's was reviewed by Nilsson in 1982. The application of electron microscopy to this area in recent years has provided much useful information and has eliminated earlier scepticism among workers about the ability of bacteria to degrade lignified wood cell walls. Studies using transmission electron microscopy together with...
A P Singh, J A Butcher
The functional anatomy of the digestive caecae and gut residence times for the marine wood borer Limnoria (Crustacea: Isopoda)
1997 - IRG/WP 97-10204
A scanning and transmission electron microscope study of the digestive caecae of the marine wood boring isopods Limnoria tripunctata and Limnoria quadripunctata, was undertaken. Two cell types were identified, containing structures indicative of absorption, secretion and storage. Cell types were distinguished according to size, the largest cell type having a large free surface area, a well develop...
C Wykes, S M Cragg, A J Pitman
CCA removal from treated wood by chemical, mechanical and microbial processing
1998 - IRG/WP 98-50101-26
Most preservative-treated wood produced and consumed in the U.S. is treated with toxic inorganic compounds containing copper, chromium, and arsenic. Because chromated copper arsenate (CCA) is fixed to the wood, treated wood has not been considered toxic or hazardous and is currently landfilled. Increasing public concern about environmental contamination from treated wood combined with increasing q...
C A Clausen, R L Smith
A study of methanogenesis and sulphate-reduction: A possible source of explosive gas mixtures in a gold mine
1989 - IRG/WP 1399
Previous work isolated anaerobic bacteria from timbers and drainage water in a gold mine. The present work identifies the predominant methanogen in the mine ecosystem as Methanobacterium bryantii and sulphate-reducing isolates as Desulphovibrio desulphuricans and Desulphotomaculum antarcticum. Laboratory studies using model systems evaluate the activity of methanogenic and sulphate-reducing bacter...
L D Abraham, J F Putterill, A A W Baecker
Preservation of basidiomycete hyphae in ancient waterlogged wood materials
1992 - IRG/WP 92-1536
Studies on waterlogged archaeological wood show that basidiomycete hyphae may persist as long as 800 years. In two pine wood samples with Phellinus pini heartrot, one from the foremast of the ship Vasa and the other from a bulwark constructed in the first part of the 12th century, numerous resin covered hyphae were observed. Hyphae with clamp connections that were associated with brown and white r...
T Nilsson, G F Daniel
Antifungal activity in metabolites from Streptomyces rimosus
1991 - IRG/WP 1495
The objective of this study was to evaluate the efficacy of antifungal metabolites from Streptomyces rimosus for controlling the growth of sapwood-inhabiting fungi: sapstain fungi - Ceratocystis coerulescens, Ceratocystis minor, Ceratocystis pilifera, and Aureobasidum pullulans; mold fungi - Aspergillus niger, Penicillium spp, and Trichoderma spp. Production of antifungal metabolites by Streptomyc...
S C Croan, T L Highley
Environmental impact of PCP and NaPCP in the aquatic and atmospheric compartment
1995 - IRG/WP 95-50040-06
PCP and NaPCP were studied for their aquatic toxicity on bacteria, microalgae and daphnids and for their behaviour in the atmospheric compartment with a climatic chamber. Results of aquatic toxicity bioassays showed that toxicity was higher at low pH. This can be explained by the pKa value of 4.7 of PCP and the higher concentration of the non dissociated form of the pesticide at more acidic pH. Vo...
P Marchal, P Vasseur, G Ozanne
New Observations and Interpretation for Tunnelling Bacteria Decay
2006 - IRG/WP 06-10579
Decay micromorphology was studied systematically for diversely preservative treated Pinus radiata and Fagus sylvatica 20 x 20 x 500 mm stakes across 13 in-ground field test sites, during a 6.5 year exposure. Sites were selected to maximise occurrence of a diverse range of decay types. Micromorphology that suggested orientation of tunnelling bacteria with the cellulose microfibrils of the S2 and S1...
R Wakeling
Comparing microbial colonisation and Decay Rates of Wood from Sound and Aphid-Killed Kenyan-Grown Mexican Cypress (Cupressus lusitanica)
2006 - IRG/WP 06-10599
Samples of wood from 10, 15, and 30-year old trees attacked and killed by the cypress aphid (Cinara cupressi) and sound Kenyan-grown Cupressus lusitanica trees were investigated for variations in moisture content, density and susceptibility to microbial decay. MC varied with tree age, a normal trend, and between samples from aphid-killed and sound trees. In samples from 10, 15 and 20-year old so...
R Venkatasamy
Ecotoxicity of furfurylated wood – Effect of leachate on aquatic bacteria
2008 - IRG/WP 08-50250
Environmental concern regarding the use of toxic preservatives such as CCA (chromated copper arsenate) has been put forward. In the EU, USA and Japan, CCA is now phased out for residential use and for use in water contact. Several ecotoxicological studies of wood treated with conventional preservatives were carried out in the late 1990s. In these studies it was concluded that the main impact is to...
A Pilgård, M Westin