Your search resulted in 334 documents. Displaying 25 entries per page.
Screening of fungal strains for wood extractive degradation
1998 - IRG/WP 98-10254
Fungal strains were screened for their ability to degrade apolar extractives in wood from scots pine. The degradation of total wood extractives by 91 different strains was monitored in stationary batch assays incubated for 6 weeks. The results obtained show that the ability of wood-inhabiting fungi to utilize wood extractives varied greatly, even for different isolates of the same species. Fungal ...
J Dorado, M J Martinez-Inigo, T A van Beek, F W Claassen, J B P A Wijnberg, R Sierra-Alvarez
The movement of iron into field test stakes
1987 - IRG/WP 2284
Failed and sacrificial stakes recovered from the Westham Island field test site were examined for their iron content. Varying amounts were recorded, which were greatest in the failed stakes. The possible role of the iron taken up by the below ground portion of the stakes, in accelerating the decay process and/or the preservative leaching is under investigation. The reaction of the iron with the ch...
J N R Ruddick, P I Morris
Preliminary investigation on the natural durability of Guayule (Parthenium argentatum)-based wood products
2000 - IRG/WP 00-40154
Conventional preservatives used to protect wood from insect and microbial damages are presently of major concern to human health and the environment. Finding alternative and economical preservatives has not been successful. Previous studies have shown that the resinous material extracted from the guayule plant (Parthenium argentatum, Gray) has both insect- and microbial-resistant properties. Unfor...
F S Nakayama, P Chow, D S Bajwa, J A Youngquist, J H Muehl, A M Krzysik
A technique for determining the efficacy of water diffusible preservative plugs for implanting in joinery in service
1987 - IRG/WP 2291
A technique is described for determining the efficacy of soluble, diffusible preservative plugs for eradicating decay in joinery. It uses blocks of Scots pine sapwood or heartwood adjusted to known moisture contents prior to the establishment of the test fungus Coniophora puteana, from a single longitudinal dowel and the subsequent introduction of the preservative plugs. Prevention of decay, eradi...
J K Carey, A F Bravery
Neem leaves, a potential source for protection of hardwood against wood decaying fungus
2005 - IRG/WP 05-30370
Neem leaves are widely recognized for their insecticidal, pesticidal, fungistatic and fungitoxic ability. The present study is to investigate the efficacy of neem leaves extractives against wood destroying microbes, a brown and a white rot. Neem leaves extractives prepared in various solvents such as petroleum ether, acetone, ethanol, methanol and hot water were tested at a concentration levels of...
S Dhyani, S Tripathi, V K Jain
Degradation of resin constituents in various wood species by the white rot fungus Bjerkandera sp. strain BOS55
1999 - IRG/WP 99-10301
In previous studies, the white-rot fungus Bjerkandera sp. strain BOS55 was shown to cause extensive degradation of lipophilic extractives (resin) in Scots pine wood. Further research was carried out in order to investigate the ability of Bjerkandera sp. for reducing resinous constituents in various softwood (Douglas fir, larch and spruce) and hardwood species (birch, beech and poplar). The greates...
J Dorado, T A Van Beek, F W Claassen, R Sierra-Alvarez
Application of oscillating pressure to improve treatability of refractory species
1987 - IRG/WP 3449
Under practical conditions a minimum moisture content of 80% demande by the German quality standard RAL-RG 411 can not be guaranteed throughout the year. Storage of logs with bark prolonges the drying process; a storage without bark must be avoided. A sufficient penetration according the standard can be achieved at least with a moisture content of 60%, optimal conditions may prevail between 100% a...
R-D Peek
Partial characterization of inhibitors extracted from pine (Pinus sylvestris) sapwood active against germination of wood rotting fungi
1988 - IRG/WP 1351
Germination inhibitors in pine sapwood could be extracted and separated with the aid of solvent partitioning and chromatography on silicic acid. The inhibitory action was tested by three different bioassays. Active fractions have been characterized by TLC and HPLC. Inhibitory activity could be correlated with phenolic compounds. The minimum active concentration of inhibitors have been determined....
J Bjurman
The effect of moisture content on the electrical resistance of timber as detected by a pulsed current reistance meter (Shigometer)
1984 - IRG/WP 2212
The literature concerning the use of the Shigometer® for detecting decay in standing trees and wood poles is reviewed and the differences of opinion over the effect of timber moisture content on electrical resistance are highlighted. A simple experiment designed to test this effect is described and the implications of the results for testing poles in service are discussed. There was a large diffe...
P I Morris, D J Dickinson
Influence of water soluble extractives on CCA fixation and leaching performance of red maple and red oak
1997 - IRG/WP 97-30133
We have observed several peculiarities in relation to CCA fixation in red maple and red oak woods such as high variability in fixation rates and leaching performance in maple and precipitate formation in solutions expressed from CCA treated red oak wood blocks at different stages of fixation. We have postulated that the extractives could be the factor of influence, as this has already been reporte...
T Stevanovic-Janezic, P A Cooper, Y T Ung
Influence of the content of organic matter of soil on the degradation of wood by soft rot fungi
1970 - IRG/WP 27
The degradation of wood specimen burried in the soil by soft rot fungi is influenced by a number of factors. These are in particular the water holding capacity, water content, content of organic matter, pH, content of mineral nutritive substances etc. The results of the interlaboratory tests, carried out within the IRG/WP let presume that the intensity of wood degradation occurs proportionally inv...
O Wälchli
Moisture content of logs under sprinklers
2000 - IRG/WP 00-40157
Logs are kept under sprinklers during storage for avoiding the development of sapstain fungi. According to literature, sapstain fungi do not develop if the moisture content is above 120%. It is supposed that, the water sprinklers maintain the log's moisture content above this value, but, very often, sapstain is found on sawn lumber cut from these logs. Logs are harvested and transported t...
M C Rose, A M Briones, M Fernández
Moisture content and other tested values in. Double layer tests of different size in Lithuania and Germany
2004 - IRG/WP 04-20299
The paper presents measurement results of moisture content and the analysis of durability trial of double layer wood in variants of varying size, conducted in Girionys, Kaunas distr., Lithuania and in Hamburg, Germany. In this trial 3 sample sets of varying size, containing 25, 50 and 100 specimens, are used. The aim of this trial is to ascertain an optimal number of test specimens. The dynamics o...
J Saladis, A O Rapp
Whitewood - An external joinery timber?
1975 - IRG/WP 253
The timber used traditionally for softwood joinery in the UK is redwood (Pinus sylvestris). In the past its ready availability in the desired sizes and quality and its durability in service encouraged little competition. However, the past decade has seen some erosion of this position, particularly through the increased proportion of sapwood in redwood supplies. Since the sapwood is less durable th...
J W W Morgan
The use of lap-joints in natural durability testing: moisture content development during 36 months outside exposure trials
2000 - IRG/WP 00-20217
Lap-joint trials (following European Standard ENV 12037) were set up with 11 different softwood and hardwood species. The main aim was to evaluate the suitability of this test standard (developed for testing wood preservative effectiveness) for natural durability testing. The moisture development has been followed during a 36 months period. In this paper, the outcomes of different moisture content...
H Militz, C J Bloom
Ability of heartwood extractives to inhibit the growth of a bacterial symbiont of Teredo navalis
2000 - IRG/WP 00-10369
Shipworms are important destroyers of wood in the marine environment, and wood users have long sought methods for preventing or limiting their attack. While heavy -duty wood preservatives are highly effective against these organisms, there is increasing concern about risks to non-target organisms. This has resulted in a gradual shift away from broadly toxic materials to either alternative material...
C S Love, A R Sipe, S C Cary, J J Morrell
Why don't more people work with Serpula lacrymans nowadays? A discussion of some of the different approaches to experimenting with this unique fungus
1989 - IRG/WP 1383
Remarkably few laboratories are currently investigating this well-known fungus. Not only has it failed to gain acceptance as a standard test organism (for wood preservative evaluation) in many countries, but is also sometimes excluded from pure research studies when it ought to be an obvious first choice as a representative basidiomycete. This paper discusses some different approaches that have be...
J D Thornton
Changes of copper and chromium content after leaching in wood impregnated with the CCB and CB preservatives
2000 - IRG/WP 00-50147
The objective of the study was impregnated with CCB and CB preservatives pine wood of moisture content varying from 12% to 55% subjected to leaching. Losses of copper and chromium were determined for individual layers of wood up to 3 cm from the girth. The results were compared to the total amount of metals determined in water extracts. The degree of leaching of metal ions from wood of 55% moistur...
B Mazela
Biocidal property of the phenolic fraction of ethanol extractives of Hopea parviflora heartwood
1993 - IRG/WP 93-30003
Natural resistance of some species of timber to fungal decay and insect damage (particularly termite) is ascribed toxic nature and quantity of certain chemical substances present in the cell wall of heartwood. These chemical substances generally known to be Phenolic and Polyphenolic compounds (Rao 1982). Earlier investigations on extractives were mainly in relation to resistance of timber to decay...
R V Krishnan, K S Theagarajan, H S Ananthapadmanabha, M Nagaraja Sharma, V V Prabhu, H C Nagaveni
Suitability of different termite species for laboratory testing
1982 - IRG/WP 1159
Different termite species were tested in the laboratory to evaluate the effectiveness of insecticides and wood preservatives in wood against termite attack. Determined were the optimum group size and composition, the matrix (vermiculite) volume and its moisture content. Choice feeding tests with fully impregnated wood blocks which are carried out according to a modified EN 117 procedure for Reticu...
U Kny, H Kühne
Analysis of the boron content of preservative treated oak and pitch pine heartwood before and after leaching
1992 - IRG/WP 92-3697
Studies to determine the effects, if any, of a variety of boron formulations on heartwood of English oak and American Pitch pine have been previously reported (King et al (1991)). Small wood blocks were treated, at 10°C or 45°C, with borax, polybor or Boracol 20 for periods of 1 month or 4 months then analysed or continuously leached with tap water for a period of 1 month. Reported results showe...
S McCutcheon, G M Smith, J W Palfreyman, B King
Penetration of oil-borne preservatives in American elm
1975 - IRG/WP 355
Pressure treatment of elm posts and cants by Rueping schedules resulted in erratic penetration. Instead of the expected gradual decrease in retention from surface inward in posts, inner zones frequently contained more preservative than the surface quarter inch. Heartwood was found penetrated when sapwood was not. There were numerous skips in treated zones. The prevalence and possible causes were i...
E A Behr
Protection of pine sawtimber and sawn timber against blue stain in Poland
1983 - IRG/WP 3193
The purpose of this paper is the synthesis of more important results of basic and applied research that have been grouped in the following problems: 1.: Fungi causing blue stain in the pine wood, occurring in Poland. 2.: Moisture content changes of pine sawtimber and sawn timber as the factor of blue stain producing fungi development. 3.: Effect of sapwood moisture content on the degree of wood st...
E Tarocinski, M H Zielinski
Factors affecting the resistance of fibre building boards to fungal attack
1975 - IRG/WP 252
Fungal decay is initiated at lower moisture contents in standard and tempered hardboards (18%) than in pine sapwood (26%). In contrast, in a saturated atmosphere, the equilibrium moisture contents of standard hardboard (14%) and of tempered hardboard (12.5%) are much lower than the moisture content permitting decay initiation whilst the equilibrium moisture content of pine sapwood (25.1%) approach...
C Grant, J G Savory
Susceptibility of heartwood of three Pinus species to attack by the subterranean termite Coptotermes acinaciformis (Froggatt)
1994 - IRG/WP 94-20026
Heartwood of plantation-grown Pinus elliottii (slash pine), Pinus caribaea (Caribbean pine) and Pinus radiata (radiata pine) was obtained from a range of locations throughout Australia and New Zealand for use in a field bioassey with subterranean termites. Timber stock was analysed for a number of stilbene and flavonoid heartwood extractive components which could contribute to variation in suscept...
M J Kennedy, L L Dixon, B C Peters