Your search resulted in 427 documents. Displaying 25 entries per page.
MDF manufactured from blends of cypress pine and radiata pine shows enhanced resistance to subterranean termite attack
2001 - IRG/WP 01-40214
Medium density fibreboards consisting of blends of the naturally durable wood species white cypress pine (Callitris glaucophylla) and non-durable wood species were manufactured in a commercial plant and subjected to a bioassay using the subterranean termite species, Coptotermes lacteus. A board composed of 30% cypress pine, 30% slash pine (Pinus elliottii) and 40% of the naturally durable hardwood...
P D Evans, S Dimitriades, C Donnelly, R B Cunningham
The natural durability of wood in different use classes
2003 - IRG/WP 03-10457
The natural durability of important European wood species has been tested on 3970 specimen in field trials. The wood was exposed at five test fields in Germany with different climates at each site in European hazard class 4 and 3 (with and without soil contact). Within EHC 3 it was distinguished between tree different expositions (end grain sheltered, unsheltered and with water trap).
The test is...
U Augusta, A O Rapp
Effects of alkali treatment on some mechanical and chemical properties of creosote treated oaks
1991 - IRG/WP 2366
To date, there is a lack of information on the effects of chemical treatment on the performance of creosote preservative treated oak sleepers. This factorial experiment was designed to analyze three main effects: species (Quercus alba and Quercus rubra) creosote treatment (treated and untreated), and alkali (NaOH) soaking (0, 1, and 10 percent). The modulus of elasticity (MOE) and fiber stress at ...
P Chow, A J Reinschmidt, E J Barenberg, L C Chang
Biocidal screening method of wood extractives by a direct use of cellulose TLC plate
2001 - IRG/WP 01-20226
Most of the methods to evaluate the biological durability of woods have focused on decay fungi and termite as deteriorating organisms and it is well known that one of the most important factors affecting the biological characteristics of wood is extractives. Bioassays for evaluating the biological activities of wood extractives have been mainly conducted with treated filter papers for termites or ...
R Yusiasih, T Yoshimura, T Umezawa, Y Imamura
Assessment of wood decay in small-scale unsterile soil-bed tests
1997 - IRG/WP 97-20111
This study is concerned with the investigation of wood decay in small-scale unsterile soil-bed tests. Tests were performed with untreated heartwood samples from five hardwood species of different natural durability classes ranging from highly perishable to very resistant. Our results confirmed the critical role of soil moisture content on wood decay. The highest decay rates were observed at moistu...
L Machek, A M Derksen, R Sierra-Alvarez
The natural durability story
1997 - IRG/WP 97-20119
Wood species with superior natural durability were in use since the beginning of timber utilisation. Their importance decreased with increasing industrial timber impregnation. In recent time, however, they gained worldwide new interest due to environmental problems involved with treated timber. In Europe a special Standard (EN 350) has been published and a multinational research project on testing...
H Willeitner, R-D Peek
The antifungal efficacy of Guayule resin
1987 - IRG/WP 3429
The Naval Research Laboratory is evaluating the non-rubber-producing portion of guayule (Parthenium argentatum) resin as a protectant for wood in terrestrial and marine service. This study phase, in collaboration with the universities of Arizona and Mississippi State, evaluates the resin's fungicidal worth. Resin-impregnated pine sapwood was exposed to brown rot fungi (Gloeophyllum trabeu...
J D Bultman, R L Gilbertson, T L Amburgey, J E Adaskaveg, S V Parikh, C A Bailey
Natural resistance of Bamboo (Bambusa sp.) to marine wood-borers in Goa waters (India)
1993 - IRG/WP 93-10032
The paper deals with the natural durability of Bambusa sp. against the attack of marine wood-borers in Goa waters. Test specimens of this species were completely destroyed within a short period of nine months due to severe attack of borers indicating its very low natural resistance. Wood-borers involved were Martesia striata (Linnaeus), Nausitora hedleyi Schepman and Lyrodus pedicellatus (Quatrefa...
L N Santhakumaran, S G Sawant
Comparing the resistance of a number of lesser known species of tropical hardwoods to the marine borer Limnoria using a short term laboratory assay
2003 - IRG/WP 03-10500
Naturally durable species of timber are used as an alternative to preservative treated timber for marine structures, but many species have not been evaluated for their potential for use in this environment. EN 275 specifies a 5-year test period - too long a period for screening tests to be economically viable. In this study, durability was assessed by measuring the production of faecal pellets by ...
L M S Borges, S M Cragg, J R Williams
Relationship of wood durability and extractives
2003 - IRG/WP 03-10493
The durability of the following five wood species, Zelkova carpinifolia, Ulmus glabra, Pterocarya fraxinifolia, Carpinius betulus and Acer laetum, were studied. Wood blocks were exposed to Coriolus versicolor under laboratory conditions according to DIN 52176 standard. After 16 weeks incubation the heart wood of Z carpinifolia showed 2,19 % weight loss, U glabra 41,69 %, C betulus 45,64 %, A laetu...
S M Kazemi
Natural durability of 4 different Larix species tested in soil contact
2002 - IRG/WP 02-10434
Importers of Siberian Larch claimed to have a material which can replace pressure treated wood in soil contact. This gave reason to investigate the durability of 4 different Larix species (L. decidua, L. sibirica, L. decidua x sibirica, L. gmelini var ologenis) coming from 7 different origins in comparison with sapwood of Pinus sylvestris untreated as well as pressure impregnated with retentions o...
A O Rapp, H Viitanen, T Nilsson
Natural durability, density and extractive contents of 42 wood species of Bangladesh.
2003 - IRG/WP 03-10490
Natural durability, density and major extractive contents of 42 lesser used or unused wood species of Bangladesh have been studied. Correlation analysis between these properties has been performed. It has been shown that natural durability of these species neither explained by water soluble nor by alcohol benzene extractive contents. Density has a weak but significant positive correlation with dur...
S Akhter, K Akhter, S C Das
Resistance of various wood species against decay by Coniophora cerebella (Pers) Duby and Lenzites trabea (Pers) Bres
1976 - IRG/WP 142
Both fungi, Coniophora cerebella and Lenzites trabea, are important destroyers of timber. Coniophora often occurs inside buildings and Lenzites trabea has been observed on southern facades of buildings, on balconies and window frames. In most instances that we investigated coniferous timber had been decayed. But both species are known to attack also various hardwoods. For this reason tests similar...
O Wälchli
Natural progression of decay in unrestrained, Southern pine sapwood exposed above ground
1995 - IRG/WP 95-20060
In this study, the natural progression of decay is being monitored in 2.4-m (8-ft) lengths of dimension lumber. The 2.4-m lengths are supported without restraint in a horizontal plane approximately 0.75 m above ground in a partially shaded field plot in southern Mississippi. The lumber is 100% sapwood. Prior to installation in the field, each piece was planed to exactly 38 by 89 mm² (1.5 by 3.5 i...
R C De Groot, R J Ross, W Nelson
Some recent studies on the marine wood-borers of the west coast of India
1982 - IRG/WP 486
Occurrence and distribution of marine wood-borers along the west coast of India from Mangalore to Kandla are presented together with the distribution pattern of all the molluscan and crustacean wood-borers so far reported from India coasts. The survey, conducted for the first time along this coast, revealed the presence of 14 species of Teredinidae, 2 species of Pholadidae, 3 species and one varie...
L N Santhakumaran
Natural resistance of timbers to marine borer attack. A laboratory test with Limnoria tripunctata
1977 - IRG/WP 430
Attack of the timber specimens was much less severe in the laboratory than in some marine localities. This is not surprising. One reason is certainly that wood-boring molluscs (Teredinidae and Pholodidae) which were missing in the laboratory are the most important wood-destroying organisms in the open sea. Another reason is that it is not possible to offer the gribbles optimal environmental condit...
H Kühne
The natural durability assessments of secondary timber species - field trials
1998 - IRG/WP 98-10297
Secondary or 'alternative' hardwood timber species can replace traditional hardwoods and contribute significantly to satisfying the overall demand for hardwoods in the UK timber market. A selection of these 'alternative' hardwoods is currently being tested at BRE-WTC for natural durability both in ground contact (to EN252) at two field sites, and out of ground c...
E D Suttie, R J Orsler
Eucalyptus globulus. Impregnability in relation with plantation and crop
1992 - IRG/WP 92-2402
Eucalyptus globulus Lasill is currently classified in Pr EN 350 on the basis of the characteristics of the first log. In practice, there are usually several following crops of branches developped on each stump in plantations. Up to a diameter of 8 cm, round wood of 2nd crop and further crops present a maximum of sapwood and characteristics which differ significantly from the basic classification a...
D Dirol
Treatability and natural durability of some lesser used or unused wood species of Bangladesh
2000 - IRG/WP 00-40170
A research study was conducted to determine the natural durability and treatability of heartwood of some lesser used or unused wood species. The treatability of species has been studied along with certain anatomical concepts association with preservative penetrability of the wood. It was observed that grain structure and presence of tyloses appeared to be correlated with penetrability of the wood....
K Akhter, M Younusuzzaman, M H Chowdhury
Biofumigation of sapstaining fungi using natural products
2002 - IRG/WP 02-10428
Control of deep-seated fungal infections in raw logs of radiata pine continues to be a challenge for achieving consistent and satisfactory protection of high value logs destined for export markets. To develop solutions for this problem, a study was undertaken to investigate inhibition of spore germination and growth of sapstaining fungi by volatiles released from a selection of natural products.
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B Kreber, C Chittenden, R N Wakeling
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 fung...
S Akhter, M D C Hale
Venezuelan net of test fields for the study of the effectiveness of treatments of non commercial timbers from natural tropical forests
2005 - IRG/WP 05-20318
A net of 13 tests fields were established in Venezuela for the study of the effectiveness of the CCA and CCB treatment in secondary or non commercial woods from natural forests, two woods from fast growth plantations wee included for promote them as treated timber mainly for fence posts uses. Partial results after two years are presented and discussed the preliminary results obtained both in field...
O Encinas, N Mora
Durability of exterior natural wood finishes in Brazil
1985 - IRG/WP 3343
Wood finishes systems were evaluated in natural weathering conditions during 5 (five) years, over "Parana-pine" (Araucaria angustifolia). Test samples results show that: - Semitransparent wood preservative stains, based on polimerized linseed oil, provided very good protection to the wood, compared with the one based on alkyd varnish; - Solid color wood preservative stains provided good durability...
D R Macedo
Durability of Anogeissus acuminata timber used for plank-built catamarans
2005 - IRG/WP 05-10551
Catamaran, the most versatile traditional fishing craft used along the Indian coast is made hitherto of solid timber of a few selected species of broad-leaved soft woods. Due to scarcity coupled with high cost of these timbers, the craft, of late, are fabricated from the wooden planks of an indigenous hardwood species, namely, Anogeissus acuminata (Yon) belonging to the family Combretaceae. Infor...
M V Rao, M Balaji, V Kuppusamy, K S Rao
Influence of felling time on the natural durability of norway spruce (Picea abies (L.) Karst.)
1998 - IRG/WP 98-10250
Natural durability was tested in a laboratory test according to EN 113. The test fungi were Coniophora puteana and Poria placenta. Additionally, the test method was modified by using water agar instead of malt agar, so that wood was the only nutrient source for the fungi. In a third attempt the samples were inoculated with Trichoderma harzianum before testing.
The trees were felled on the 22.7.97...
M Hirmke, K Messner, J Fellner, A Teischinger, R Wimmer