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Trend in entomology of wood in use and in storage in Nigeria
1978 - IRG/WP 180
The current and potential impact of biotic agents of wood deterioration in Nigeria is reviewed, with emphasis on the insects and marine borers, their recognition and mode of damage. Some essential areas have no doubt been neglected and these are highlighted, while future lines of approach are outlined.
M O Akanbi


Conservation of wooden cultural property
1994 - IRG/WP 94-30038
A survey of the conservation of wooden archtitectual monuments, art objects and archaeological finds is presented. Each of the three areas has typical conservation problems which reqire the use of selected wood preservatives and consolidation agents. Furthermore specific protection and consolidation methods are necessary. A precise damage diagnosis with non-destructive testing methods is the first step in a careful conservation work.
A Unger, W Unger


Über Wespen als Holzverderber - Schäden, Ursachen, Bekämpfung
1978 - IRG/WP 189
Observations and a number of actual cases over recent years show that wasps have been associated more frequently with damage to wood. The nature of such damage and the agents involved are as follows: 1. Decay following infestation by Woodwasps (Siricidae). 2. Punctate marks caused by superficial gnawing and also boring into wood by larvae of the Dock sawfly (Tenthredinidae). 3. Damage due to superficial scarification by Vespids (Vespidae). Little is known as yet of the causes of this damage and its connection with the insects. A better understanding would help in preventing damage to construction components as well as the loss of wood and would benefit the reputation of wood as a building material. Methods of prevention and control and of remedying the damage are mentioned, based on tests and practical experience.
S Cymorek


Report of an investigation of damage by wood ants in buildings in Sweden
1976 - IRG/WP 148
Wood ants in buildings occur everywhere in Sweden, particularly in maritime districts and in vicinity of larger lakes. The damage caused by Camponotus herculeanus does not differ from that caused by Camponotus ligniperda. The former occurs in all Sweden, the latter only in southern Sweden. The damage is to be found almost exclusively in dwelling houses (week-end cabins and "all-the-year round" houses) in or close to forests.·Buildings of all ages are liable to wood ants attacks. All wooden part of houses, particularly the walls, can be infested. Sound timber is much more desirable to the insects than wood that is infected with wood-rotting fungi. The construction of the building can sometimes affect the frequency of the damage. This is the case particularly with cabins which lack basements. The decisive part in wood ant migrations from forest to buildings is the distance from the edge of the wood: the shorter this distance the greater the danger of invasion.
V Butovitsch


Wood preservation in the Australian beekeeping industry
1988 - IRG/WP 3473
This paper reports the results of a survey of Australian commercial beekeepers working 200 or more hives in June/July 1985. Nine hundred and forty seven apiarists were asked to participate and to provide information on their wood preservation methods, painting procedures and maintenance of bee boxes. Three hundred and eighty-four apiarists returned completed questionnaires (41%). The main wood preservatives used are copper naphthenate solutions (45%), linseed oil (8%), copper chromated arsenate (3%), hot wax (9%), copper naphthenate solution in linseed oil (3%), linseed oil/wax mixtures (3%) and paint (23%). The majority of apiarists (96%) paint treated bee hives, but there is considerable variation in wood preservative treatment procedures and paint application. Most wood preservative treatments (95%) are of the 'do-it-yourself' variety, radiata pine being the most utilized timber. The bottom boards of bee hives are considered the most susceptible to wood decay and subterranean termite damage, as are cleats, stands or any wood in ground contact.
P J Robinson, J R J French


Wood decay in Danish buildings
1985 - IRG/WP 1261
At Technological Institute identification of fungi and advisory activity concerning repair of damages has taken place since 1935. Statistical analyses based on material from 1982 and 1983 are compared to earlier investigations worked out by L. Harmsen. The material shows that building traditions influence the diversity and frequency of fungal species. Many fungal damages in the last decade have showed that it is very important to use timber in a suitable manner not forgetting old building traditions. The conditions of fungal attack must be analysed and followed up by improvement of constructive and chemical wood protection.
A P Koch


Practical testing of wood preservatives to prevent weathering damage and infection by micro-organisms on spruce and pine
1989 - IRG/WP 3530
Brush application, is generally used to prevent wooden window frames from decay caused by influence of weathering and fungi. Accordingly 10 boards of pine (Pinus sylvestris) and spruce (Picea abies) were treated with 10 commercially used wood preservatives. The efficiency of fungicides by using chiptest and blue stain test (EN 152), the effectiveness against weathering as well as the course of colonization of microfungi were measured on boards, that had been hurted by sawing. Results after one year's exposure showed that neither the normally required amount of 250 ml/m² nor the effective depth of penetration of the fungizidal equipment had been realized by using brush application. The smaller the permeability of the coating system, the more likely ideal conditions for the growth of fungi (e.g. basidiomycetes) are provided, answering hurtings of the coating and moisture contents of more than 30%. The variety of fungi (on pine 32 and on spruce 17 species) can be a result of anatomical differences and distinguished compounds of the wood species. After 24, respectively 36 weeks of exposure the frequent occurrance of basidiomycetous yeasts (Cryptococcus albidus, Rhodotorula mucilaginosa), blue stain fungi (Aureobasidium pullulans, Hormonema dematioides), Epicoccum nigrum, Alternaria alternata and Phoma species was noted.
R Gründlinger, O Janotta, H Melzer, K Messner


Influence of bark damage on bluestain development in pine logs
1997 - IRG/WP 97-10197
Mechanized harvesting of conifers can lead to extensive bark damage, with the resulting wounds providing suitable entry points for bluestain fungi that are not associated with bark beetle vectors. However, the amount of bluestain colonisation can vary greatly between the different types of wound. To evaluate the effect of wound type seven different types of wounds were artificially created on freshly felled logs of Corsican pine. These ranged from barely visible punctures, to the removal of large strips of bark, simulating typical harvester damage. The logs were left in the field exposed to natural inocula of wood degrading fungi and assessed after 6 and 12 weeks. Results indicated that surface area of injury was not the best parameter for predicting the rate and extent of staining. Minor disruptions of the bark e.g. crushing and punctures, were sometimes associated with substantial amounts of stain development. Wounds with flaps of loosened but still attached bark were especially susceptible to bluestain colonization, but additional damage to exposed wood surfaces did not result in more stain. Stain development was strongly associated with the edges of wounds where the bark and exposed wood met. Excluding potential bluestain vectors such as bark beetles and weevils by enclosing the logs in netting did not markedly reduce stain, suggesting that micro-arthropods such as mites play an important part in disseminating bluestain fungi to wounds produced during harvesting and log extraction.
A Uzunovic, J F Webber, D J Dickinson


Damage by wood-attacking insects in buildings in Sao Paulo State - Brazil. (including errata slip)
1978 - IRG/WP 175
From 1974 to 1978 up to 602 buildings attacked by wood-boring insects were inspected by Instituto de Pesquisas Tecnologicas in Sao Paulo State - Brazil. Damage was caused mainly by subterranean termites, dry-wood termites and wood-attacking beetles. Up to US $ 1000,000 is the amount needed to control such insects in the buildings inspected
A T De Lelis


How to keep coated wood structures sufficiently dry to avoid damage caused by rot
1991 - IRG/WP 2376
During the last ten years, a new type of problems with wood rot has emerged in Scandinavia. Thousands of houses have been damaged by wood rot attaching to the exterior wood panel. This paper provides an overview of finished and ongoing work in order to identify the cause of these problems. In field tests, the moisture conditions were measured in panels coated with different paint systems. The influence of the panel structure and end-grain sealing on the moisture balance was also studied. The results from these tests show a large difference in the moisture balance between panels with different exterior wood coatings. In laboratory tests, the transmission of water vapour through paint films was measured using a modified cup method, which provides more realistic conditions for coated wood than the common cup method. One interesting observation made in the studies reported here is that latex paints seem to be much more permeable at high levels of relative humidity than earlier research has shown.
S Hjort


Inhibition of wood decay and termite damage by calcium precipitation
1996 - IRG/WP 96-30111
Fungal decay of wood in service, especially brown rot, results in billions of dollars (US) of losses annually. Recent environmental restrictions, both U.S. and international, are limiting or eliminating the use of broad spectrum biocides for wood preservation, primarily due to problems with disposal. In order to design new, environmentally benign methods for control of wood decay fungi, it is essential to understand the precise sequence of biochemical events as wood is colonized. The production of polygalacturonase (PG) and hydrolysis of bordered pit membranes during incipient brown-rot decay has recently been described by our laboratory. One key to pectin hydrolysis by plant pathogens has been shown to be fungal production of oxalic acid which lowers the pH of the substrate and chelates calcium ions. Production of oxalic acid may serve a similar role during incipient wood decay as calcium oxalate has been visualized by scanning electron microscopy during both brown-rot and white-rot decay. Therefore, it was hypothesized that in situ precipitation of existing calcium ions in wood may prevent the cascade of biochemical events involved in colonization of wood by brown-rot fungi, expecially hydrolysis of bordered pit membranes. Preliminary experiments in our laboratory have shown that brown-rot fungi, white-rot fungi, and termites are inhibited from effecting weight loss of wood following pretreatment of wood blocks with the selective water soluble calcium precipitating agent N,N-naphthaloylhydroxylamine (NHA).
F Green III, T A Kuster, L Ferge, T L Highley


Wooden windows, avoidance of damage via constructional measures
1990 - IRG/WP 3591
Increasing awareness of the environment reinforces the trend to use wood as a building material for windows in modern building constructions. Wood is a natural building and construction material. Under certain circumstances such as persistent humidity exceeding 30%, wood is rapidly degraded by decay fungi into CO2 and inorganic salts. The cost caused by damage (e.g. replacement of windows) represents a considerable burden on the economy. Damages on wooden windows can not only be reduced to wood decay fungi acting destructive. Conventional brush- and diptreatment provide only superficial marginal protection. Constructive wood protection (integral solution) taking into account the static and physical properties of the building material wood is of central importance. The film demonstrates the most important reasons for damage and their consequences occuring during planing, constructing and during incorporation of windows into the building. Directions and suggestions for a solution of the problems are given. Suitable isothermic incorporation of the window into the building has significant importance. Formation of condensate, also due to lapse in housekeeping (e.g. lack of ventilation) may be avoided to a far extent. Also damage and reasons for damage, resulting from misconstruction in the area of the glass seam (e.g. sealents that harden) and transom and casement frame areas (e.g. lacking of end caps on the anti-rain strips) are demonstrated in the present film.
R Gründlinger, K Messner


Development on Damage Functions of Wood Decay for Building Envelope Design
2005 - IRG/WP 05-10556
For the hygrothermal analyses of building envelope systems for insulation design, we tried a natural decay test of wetted wood specimens without any inoculation of fungi. Three principal experimental types: under steady-state conditions (Experiment A), at a cyclic water dripping under Non-steady conditions (Experiment B) and at a cyclic water dipping under-steady conditions (Experiment C), were carried out for this purpose. After these tests, each specimen was determined its longitudinal compression strength. The detection of decay was checked this standard strength value by species according to Japanese building code and its corrected value by these moisture contents. As the results of the Experiment A, some fungal growth was observed within 10 weeks at the moisture contents of levels between 30wt% and 70wt%. As the results of the Experiment B, the simulated condition of short time condensation in summer was observed fungal growth but not affected decay problems within 124 weeks. As the results of the Experiment C, the simulated condition of periodical wetting as under floor or bottom of cladding was not observed any decay.
H Suzuki, Y Kitadani, K Suzuki, A Iwamae, H Nagai


Inhibition of termite damage by N'N-napthaloylhydroxyamine (NHA): Reticulotermes flavipes (Kollar) vs. Coptotermes formosanus Shiraki
2000 - IRG/WP 00-10354
The calcium precipitating agent NHA has been shown to protect southern yellow pine (SYP) from wood decay and termite damage comparable to CCA in field tests (Gulfport, MS) for two years (Crawford and Green, 1999). In a collaborative study, SYP wood blocks were vacuum treated with three concentrations of aqueous NHA and exposed in a no-choice test to Eastern subterranean termites (FPL, USA) and Formosan subterranean termites (WRI, Japan) to determine protection against termite damage. Individual blocks (leached and unleached) were exposed to R. flavipes (AWPA) or C. formosanus (JWPA) for 3-4 weeks. Mean weight loss of wood blocks after termite exposure ranged from 0.0 to 18.0% for R. flavipes and 6.0 to 20% for C. formosanus. Wood blocks exposed to R. flavipes were completely protected by 0.5 and 1.0% NHA, but weight loss in similar blocks challenged by C. formosanus were 6.0% and 6.2% respectively at the same concentrations. NHA acted as an effective termiticide for R. flavipes with 100% mortality after 3 weeks, but only soldiers were preferentially killed in C. formosanus. Formosan subterranean termite workers showed enhanced resistance to NHA treatment when compared to Eastern subterranean termites.
F Green III, S T Lebow, T Yoshimura


Evaluating the natural durability of native and tropical wood species against Reticulitermes flavip
2004 - IRG/WP 04-10539
Environmental pressures to eliminate arsenate from wood preservatives has resulted in voluntary removal of CCA for residential applications in the United States. A new generation of copper organic preservatives has been formulated to replace CCA for decking and in-ground applications but there is no guarantee that these preservatives represent a permanent solution to all related problems. Therefore, it is still necessary to evaluate alternative treatments, as well as naturally durable wood species, in order to be prepared for future changes in the field. In this study, six hardwoods and six softwoods have been evaluated for their ability to resist termite damage by Reticulitermes flavipes in a 4-week laboratory no-choice test. In addition, moderately resistant Douglas-fir and southern pine wood blocks were evaluated after treatment with copper borate, copper naphthanate, and N,N-naphthaloylhydroxylamine (NHA). Erisma, juniper, ipe and white-cedar were shown to be highly resistant. NHA protected Douglas-fir and southern pine as effectively as copper borate or copper naphthanate. These results suggest that some naturally durable wood species, both tropical and native, can inhibit R. flavipes as effectively as preservative treatment.
R A Arango, F Green III, K Hintz, R B Miller


Risk of pulmonary damage as a result of an evaporation of ca. 50 ppb = 42 mg HF, evaporated from wood treated by difluorides
1987 - IRG/WP 3401
In this review of the literature the effects of fluorides and fluorine on man are described, especially the low level effects of inhaled HF on human beings. The term "fluoride" is used as a general term everywhere, where exact differentiation between ionic and moluecular forms or between gaseous and particulate forms is uncertain or unnecessary. The term covers all combined forms of the element, regardless of chemical form, unless there is a specific reason to stress the gaseous elemental form F2, in which case the term "fluorine" is used.
H F M Nijman


Poplar wood and its damages in Iran
1987 - IRG/WP 1332
In Iran poplar planting has been used for many centuries ago specially in regions without forests. It had rural uses in ancient time, but recently many fast growing poplar species have been planted and many hybrids also have been planted; the following species had been cultivated widely in Iran: Populus nigra L. var. italica, Populus alba L., Populus caspica Bornm, Populus deltoides L., Populus X. euramericana, Populus euphratica Oliv. The sapwood and heartwood of these species which are planted in humid Caspian region of Iran have been attacked severely by different fungi species. But in Central plateau of Iran and Eastern and Western part of Iran they are attacked by Isoptera (Cokoptera), Lepidoptera and also Hymenoptera and specially termites. The miseltaes (Viscum album) attack severely in Mazandaran region to poplar species. Beside that in steppic region of Iran frost rings cause severe damage.
D Parsapajouh, P Niloufari


Protection of southern pine using N,N-Napthaloylhydroxylamine: Field tests, soft-rot cellars and aquatic bioassay leach testing
1999 - IRG/WP 99-30204
Recent environmental restrictions are limiting the use of broad-spectrum biocides for wood preservation. There is an urgent need for new, sharply targeted, environmentally benign wood preservatives. N'N-Napthaloylhydroxylamine (NHA), a water-soluble calcium-precipitating agent, has been shown to inhibit decay by brown-rot and white-rot fungi in soil-block tests and prevent damage by Eastem subterranean termites under lab conditions. In order to further evaluate the capacity of NHA to prevent decay and termite damage, SYP stakes were pressure treated with three concentrations of NHA (0.1, 0.5 and 1.0%) and CCA (1.0%) and placed in-ground at the Harrison Experimental Forest, Gulfport, Mississippi, in June, 1997. Similarly, treated sticks were placed in soft-rot fungal cellars at FPL. One percent NHA-treated stakes were also leached for 72 hours in water and the leachates tested by an acute, five dilution bioassay using Ceriodaphnia dubia in EPA Protocol 600/4-90/27F. Results to date: 1) NHA stakes (0.5 and 1.0%) are as durable as CCA; 2) NHA does not inhibit soft-rot fungi and, 3) NHA is a relatively benign molecule with LD50 130-fold less than copper for C. dubia.
D M Crawford, F Green III


Proposing innovative technologies in the control of dry-wood insects
1985 - IRG/WP 1262
This paper discusses the social-economic problems involved in the biological evaluation of dry-wood insects with particular reference to Nigeria. It also discusses prospects of applying non-conventional methods of control against such insects, integrating these with the conventional preservatives as a control strategy. This discussion follows attempts made to identify the major dry-wood insects in Nigeria as a base for raising cultures required in screening wood preservative materials. Hitherto, this allimportant aspect of wood science suffered underserved relegation in Nigeria. The commonest dry-wood insects identified so far include two species of dry-wood termites (Kalotermidae) Cryptotermes havilandi (Sjostedt) and Cryptotermes brevis (Walker); and beetles Lyctus africanus Lesne (Lyctidae), Minthea rugicollis (Walker), Bostrychoplies cornutus Olivier, Xyloperthella picea Olivier, Heterobostrychus brunneus Murray, Xyloperthodea nitidipennis Murray, and Apate spp. (Bostrychidae).
M O Akanbi


Detection and estimation of Hylotrupes bajulus L. wood damages by ultrasonics
1990 - IRG/WP 2350
To evaluate the validity of the ultrasonic application in the detection and evaluation of wood damages produced by Hylotrupes bajulus L. larvae, some laboratory tests were made with small wood samples. The pulse through transmission method was used. The transit time of ultrasonic pulses in transversal sections, radial and tangential, of the samples was measured. The increment of the transit time of ultrasonic pulses with respect to clear wood gave to this method the way to estimate the damage grade.
G Prieto


Evaluation of tropical wood by-products as a potential source for termite control products
2001 - IRG/WP 01-10408
Termites damaging in houses represent an ever growing threat in Europe, where the phenomenon has accelerated during the last ten years, as well as in the tropics, where infestations are permanent. To fight against this plague, the current methods used, through injection of organochloric or organophosphorized products into the timber structures and walls, are belonging to the past due to the toxicity and harmful consequences of their use on the environment. New techniques were developed and research organisations are still working on minimizing the environmental impacts through the elaboration of new products. Some tropical wood species from French overseas territories (mainly French Guyana), like Ocotea rubra, Licaria canella and Aniba parviflora (Lauraceae), contain repellent, antifeeding or toxic substances which might be extracted to obtain molecules to be used for new wood preservatives. CNRS and CIRAD-Forêt are currently elaborating techniques that will allow to discriminate the possible effects of various molecules contained in sawdusts as regards to termites. Both termite species, Heterotermes indicola and Reticulitermes santonensis, have shown different behaviours depending on the wood species. These wood species were consequently classified according to their repulsive, antifeeding or toxic effects against both termite species studied. Considering the results obtained, it would then be worthwhile to use wood wastes from sawmills. Being so, the up-grading of by-products can be the basis for formulations of new wood preservatives with low environmental impacts and still providing durability against termites to wood species with a low natural durability.
A Zaremski, S Robert, J-L Clement, D Fouquet


Research studies on infecting behaviour of Fomes fomentarius (L. ex FR) Fr. and its physical control in the wood yards of the Hyrcanian (Caspian) forests of Ira
1996 - IRG/WP 96-10179
Due to illegal cutting, girdling and ringbarking many damages of tinder fungus (Fomes fomentarius (L. ex Fr) Fr.) are seen on beech, poplar, oak and birch at Hyrcanian (Caspian) forests of Iran. The beeches (Fagus orientalis Lipsky) are damaged highly and the beech community of Fagetum are infected from 800 meter altitudes at Gorgan (East of Caspian forests) to 600 meters altitudes at Gilan (West of Caspian Forests belt of Iran) and totally the damage is seen up to a height of 2000 meters.
P Niloufari


Wood attacking insects in urban areas in Sao Paulo State - Brazil
1985 - IRG/WP 1267
From 1974 to 1984 the investigators of Wood Division (IPT) inspected, for insect attack, more than 1,500 buildings of several kinds: commercial, residencial and historical buildings, houses and industries. In all cases, IPT was asked to give advices on control and erradication. During that time three papers concerning this problem were published (Cavalcante, 1976; De Lelis, 1978; Zanotto & Canedo, 1982). This paper, comprising partial data from the above papers, lists insects found, estimates the costs necessary to control them, and reports the most common factors that have been found favouring infestations in the inspected buildings.
P A Zanotto, M D Canedo, D A T Lelis


Northern oak wood and its damages in Iran
1988 - IRG/WP 1377
The Northern oak species of Iran designated Quercus castaneaefolia C.A.M. is distributed widely in caspian littoral. In natural conditions (healthy) has favourable quality and it is used mostly in rural construtions, sleepers, parquets, cross arms for electric and communication poles, it is used also indoor and window construction, benches and finally veneer. This wood in the case of sleepers and cross arms are impregnated. This wood in himud caspian region in contact with soil has a durability about l5 years, while in case it has been installed on foundations has a durability of 20 to 25 years. Different insects, specially from Cerambycidae and Anobium, Platypus and Lyctus attak to oak wood severly, specially to its sapwood. Also many lignivorous fungi attack this wood which are mostly from genus of Coriolus, Fistulina, Phellinus, Polyporus, Stereum, Schyzophyllum... etc. The coefficient of impact bending in decayed wood (k/d²) decreases about 80% in comparasion to the healthy wood, so due to this results, preservation and control of rail road ties and cross arms should be performed in its best methods.
D Parsapajouh, P Niloufari


Subterranean termites of economic importance in suburban Melbourne: Wood structures most frequently attacked and damaged
1990 - IRG/WP 1430
An examination of wood structures in forty buildings actively being attacked by subterranean termites in Melbourne revealed that all buildings were being attacked and damaged by Coptotermes species. This indicates the economic importance of these species. Hardwoods were more frequently infested than softwood species. The implications of these findings are discussed in relation to termite control, with particular emphasis on eradicating infestations using arsenic trioxide and mirex-treated wood decay blocks.
J R J French


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