Your search resulted in 13 documents.
Laboratory tests on natural resistance to Cryptotermes brevis (Walker) attack of native hardwoods for crossarms production
1985 - IRG/WP 1266
Eletropaulo (Eletricidade de Sao Paulo S/A) and IPT (Instituto de Pesquisas Tecnologicas do Estado de Sao Paulo S/A) are carrying on a study to evaluate wood species for crossarms in replacement of Aspidosperma polyneuron - Apocynaceae (Peroba-rosa) traditionally used for this purpose. Nineteen Amazon wood species were elected, with physical and mechanical properties equal or better than those presented by Peroba-rosa. Biological tests with these woods and physical tests of crossarms were carried out. Here is presented the results of the resistance test to Cryptotermes brevis attack.
M D Canedo, A T De Lelis
The susceptibility of 35 Amazon wood species to Cryptotermes brevis (Walker)
1982 - IRG/WP 1160
Laboratory tests were carried to evaluate the susceptibility of 35 Amazon hardwoods to Cryptotermes brevis (Walker). The results were analysed statistically and showed that five wood species were non resistant, nine were resistant and the other twenty-one in between those classes of resistance.
M D Canedo
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
Compatibility of deltamethrin with wood-finishing and construction materials
1993 - IRG/WP 93-30010
Under normal use conditions, treated wood comes to close contact with the structural components of a buiLding, and/or receives finishing, forming a new interface, which can affect the performance of a new product such as deltamethrin. To study this possibility, block-tests of Parana-Pine (Araucaria angustifolia), measuring 12 x 24 x 0.5 cm³ (with the largest dimension parallel to the wood-grain), received brushing treatment with deltamethrin and kerosene in two different concentrations: 0.02% (w/w) and 0.04% (w/w). After 20 days under laboratory conditions, the block-tests received a superficial finishing with poliurethan varnish, enamel paint, oil paint (alkidic) and latex paint and were fastened in close contact, through rubber band, with bricks, building cement, concrete blocks and plaster. A set of pieces made up of these construction materials was treated with deltamethrin in the same concentration as mentioned above, forming a reference series. The test against dry-wood termites (Cryptotermes brevis) was carried out 21 months after the treatment. The deltamethrin proved to be very effective in wood protection, independently of the finish used and the type of construction material in contact with the wood.
E S Lepage
Cryptotermes brevis - a silent earthquake for the wood structures in a World Heritage city in the Azores Islands
2016 - IRG/WP 16-50316
In the Azores archipelago the exotic drywood termite Cryptotermes brevis, detected in early 2000’s, is destroying the wood structures of the typical buildings and is already considered the main urban pest in these islands. This work aims to show the spread evolution of this pest along the last six years in the first Portuguese city classified as world heritage by UNESCO, Angra do Heroísmo. For six years, several buildings were monitored, using traps with glue to catch the alates (flying individuals), during the swarm season that occurs, normally, from the late spring until the end of summer. The number of captured individuals was used to determine the density per building. This data was analysed with a GIS in order to build risk maps of the termite spread in space along time. The results clearly indicate that the pest species is expanding. The city centre is no longer the only affected area. The percentage of buildings that are affected or in risk to be affected is very high in the entire city. Traditional construction, with timber load bearing structures, is being replaced by metal or other materials. There is still no Integrated Urban Pest Management implemented in the region or in the city. Therefore, with time, timber structures might become restricted to exist only in buildings like museums, churches or palaces.
O Guerreiro, P A V Borges, L Nunes
Feeding preference behaviour of Crytopermes cynocephalus Light and Coptotermes curvignathus Holmgren on twenty-eight tropical timbers
1985 - IRG/WP 1251
A study on the feeding preference behaviour of a dry-wood termite Cryptotermes cynocephalus Light and a subterranean termite Coptotermes curvignathus Holmgren on 28 species of tropical timbers has been conducted. The weight-loss of individual timber and the mortality of termite was·recorded after 5, 10, 15, 20 and 25 days of exposure. The results reveal that there are only five species among 28 species of wood which are completely repellent to both the dry-wood termite Cryptotermes cynocephalus and the subterranean termite Coptotermes curvignathus. These five wood species are Dalbergia latifolia, Eusideroxylon zwageri, Intsia bijuga, Lagerstromia speciosa and Tectona grandis. There are eight wood species which are repellent to Cryptotermes cynocephalus and seven wood species which are repellent to Coptotermes curvignathus. There are also only seven wood species which are completely arrestant or highly arrestant to both species of termite. Agathis alba and Mangifera indica are classified as highly arrestant to both the dry-wood and the subterranean termites. Other species are classified between moderately repellent to highly arrestant.
Assessment of the natural durability of four Ghanaian hardwoods against the white-rot fungus Coriolus versicolor and soft-rot using laboratory tests
2003 - IRG/WP 03-10498
The natural durability of two lesser-utilized species (LUS) (Corynanthe pachyceras Welw. (pamprana) and Glyphaea brevis (Sprengel) Monachino) (foto) from three forest districts, and two related primary species (Nauclea diderrichii (de Wild.) Merr. (opepe) and Nesogodornia papaverifera (A. Chev.) R. Capuron.) (danta) from one district in Ghana is assessed against Coriolus versicolor Linnaeus Quelet and soft rot. Durability of wood from different radial and axial positions in each stem is assessed using modified EN113 and EN(V)807 tests. Mean percentage weight losses (%MWL) are compared to determine the influence of position in the stem and growth site (for the LUS) on durability. Natural durability classes are also determined. Radial and axial variations in durability exist within the stems of all four hardwoods against C. versicolor and soft rot. At the same axial position, radial durability normally increases progressively from the outer sapwood towards the inner heartwood, whereas at the same radial positions, durability normally decreases from the base to the crown of the stem. Occasionally, the middle and crown are more durable. Growth site also influences durability of the LUS. For the primary species, the natural durability classes determined in this study differ from those assigned to them in literature. Durability ranking for the hardwoods against white rot is: N. diderrichii> C. pachyceras> N. papaverifera> G. brevis; with that against soft rot being: C. pachyceras >N. diderrichii >N. papaverifera >G. brevis.
C Antwi-Boasiako, A J Pitman, J R Barnett
Notes on the resistance of tropical woods against termites
1985 - IRG/WP 1249
This paper deals with a descriptive account on the effect of experimental methods, matrix, species of termites, solid wood and wood extract on the resistance and repellency of woods against three species of termites, i.e. Cryptotermes cynocephalus Light; Coptotermes curvignathus Holmgren and Reticulitermes lucifugus (Rossi). Two methods of experiment were used, the Forced Feeding Test and the Feeding Preference Test. The Feeding Preference Test method was found more appropriate for assessing the arrestancy and repellency of woods against termites. This method is probably appropriate for predicting the normal feeding behaviour of termites in the field.
Laboratory tests on the residual effects of pyrethroids against termites after one year
1983 - IRG/WP 1216
Due to recent restrictions of ecological nature which most of pesticides are been submitted, it is necessary in wood preservation to test new products and formulation with low mamalian toxicity for substitution of the traditional products. The efficiency of five synthetic pyrethroids in comparison to the traditional organo-chlorinated pesticide chlordane was evaluated. Wood blocks impregnated with those products in different concentration were exposed to dry-wood termites one year after the treatment. Decamethrin, Cypermethrin and Fenvalerate gave the best results.
A M F Oliveira
Termite resistance of twenty-eight Indonesian timbers
1982 - IRG/WP 1150
A comparative study of termite resistance of 28 Indonesian wood species has been conducted using small samples measuring 5 x 10 x 20 mm³. The drywood termite Cryptotermes cynocephallus (Kalotermitidae) and the subterranean termite Coptotermes curvignathus (Rhinotermitidae) were used in the study. A resistance classification was derived on the basis of cluster analysis. The result reveals that Albizia procera, Dalbergia latifolia, Eusideroxylon zwageri, Tectona grandis and Intsia bijuga are completely resistant to both species of termite. Albizia chinensis and Artocarpus integer are resistant only to Cryptotermes cynocephallus, but vary between resistant and moderately resistant to Coptotermes curvignathus. Other wood species are classified as moderately resistant, susceptible or very susceptible.
Nana Supriana, P E Howse
What Can Fecal Pellets Tell Us About Cryptic Drywood Termites (Isoptera: Kalotermitidae)?
2009 - IRG/WP 09-20407
Drywood termites (Isoptera: Kalotermitidae) are serious economic pests of both plants and seasoned wood (furniture, wood frame structures). Currently, five species of kalotermitids are known to occur in the Hawaiian Islands: Neotermes connexus, Incisitermes immigrans, Incisitermes minor, Cryptotermes brevis, and Cryptotermes cynocephalis. These termites are difficult to detect and observe due to their cryptic habitat. Unlike termites that nest in the soil, and forage outward for wood, drywood termites nest directly in their food source. Often, the only outward sign of termite infestation is the presence of small fecal pellets, expelled from the gallery system through small holes in the wood surface. This report reviews recent research indicating that these fecal pellets may be a valuable source of information on the biology of these cryptic insects, including the identity of the termite species, the relative cellulose content of the food source, and the size and even the age of the population.
J K Grace
Major insects attacking timber used for building purposes and a practical approach for their control
1990 - IRG/WP 1449
Lignocellulosic materials like wood, bamboos, palmyra palms, reeds, leaves and grasses have been the oldest materials used by human beings. Although with the rapid pace of industrialisation, specially in several western countries, wood began to be replaced with alternative materials like cement, steel etc. yet its use has not vanished even in highly developed countries. Some of the reasons for this are its inherent advantages over other building materials. Wood is a renewable resource, economical in use, easy to work with and process and possesses adequate strength. In addition, it has better thermal, electrical and accoustic insulation properties and can withstand fire resulting in lesser damage to buildings. In developing countries, like India, where resource exploitation has not kept pace with rapid population growth, the use of wood in building construction has dwindled in preference to alternative materials due to certain reasons like:- (i) use of cement, steel, etc. is regarded as a symbol of industrial advancement, (ii) naturally durable species are becoming scarcer and costly and (iii) lack of knowledge amongst consumers, engineers, designers regarding processing techniques, scientific designing of wooden structures, choice of suitable species according to strength etc. The component of wood varies from 10-15 percent of the total building cost (1) Presently it is reported that nearly 3 million cum. is utilised for building construction which is likely to increase in the near future (2) as there is a shortage of the order of 6 million urban and 18 million rural units. At several recent International consultations on the utilisation of wood in buildings, it has been emphasised that wood, as a constructional material, has not been receiving adequate attention in the training programmes of architects and engineers and that there has been a complete neglect of the large technological potential that exists for replacing solid wood by plywood, particle board, wooden board etc. Introduction of proper processing techniques, careful selection of species for the end use, proper grading practices, reduction of presently permitted safety factors through mechanical grading and improved designing and timber engineering, progressive adoption of re-constituted wood products can lead to considerable savings of wood. The ill organised state of sawmilling industry in most of the developing countries restricts investment potential for essential operations - processing, grading, design development etc. Conversion of timber in advance and stocking of graded and processed sizes and prefabricated components is not possible when units operate in a very small scale and in widely scattered locations. Lastly, sufficient education and confidence in the feasibility of timber structures are yet to be developed amongst consumers, engineers, architects and manufacturers. Apart from timber other forest based materials like bamboo, thatch grasses, leaves, reeds etc. for rural housing cannot be ignored specifically in developing countries like India, where bulk of the population lives in villages and uses these materials without processing. While several problems in the introduction of scientific processing of building materials of lignocellulosic origin, including reconstituted wood, arise due to socio-economic factors and organisation of the industry, the need for research to develop simple and economical processing techniques cannot be ignored for any developing country. It may, however, be pointed out that in India there is already enough data base on properties and working stresses of timbers, seasoning and preservation processes, timber engineering designs, use of reconstituted wood etc. Some of these aspects are briefly highlighted here.
V R Sonti, B Chatterjee
Isolation and evaluation of Lactobacillus brevis from chilli waste for potential use as a wood preservative
2011 - IRG/WP 11-10749
Lactic acid bacteria were isolated from chilli waste and evaluated for their ability to arrest wood rotting basidiomycetes. In previous work a quick screening method using 96 well plates and measuring absorbance to determine fungal growth was developed specifically to investigate the efficacy of isolated bacteria against wood decay fungi. Using this method, one bacterium (isolate C11) was identified from three bacterial isolates as having significant antifungal properties against Oligoporus placenta. This isolate was identified as Lactobacillus brevis by 16S rRNA gene sequencing and BLAST analysis of the NCBI database. To determine antifungal activity in wood, Pinus radiata blocks were impregnated with L. brevis strain C11 cell free supernatant (CFS) and exposed to brown rot fungi O. placenta, Antrodia xantha, and Coniophora puteana. The CFS treated timber demonstrated resistance to degradation from all fungi especially when L. brevis was incubated for one week before filtering the culture to retrieve the supernatant. To determine the nature of the bacterial metabolites affecting fungal growth, the affect of pH, temperature and proteinaceous enzymes on the CFS was assessed using the 96 well quick screening method. The antifungal metabolites were heat stable and not affected by proteinase K, but were affected by neutralisation with NaOH suggesting the metabolites were of an acidic nature.
D O’Callahan, T Singh, I R McDonald