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Preliminary attempts towards the development of a small scale termite rearing chamber. Progress report
1983 - IRG/WP 1203
The results suggest that there is no evidence that the volume of the rearing chamber plays a part in the settlement of a colony. These rearing chambers present a factor of productivity (final enumeration)/(initial enumeration) of roughly 2 after one year. 90% of the colony survived. This method of breeding can be considered as feasible and cheap.
M Argoud, J C Palla, R Sternalsky


Preliminary attempts towards the development of a small-scale termite rearing chamber
1982 - IRG/WP 1148
The paper suggests how to prepare a small-scale rearing chamber for termites which might be used for testing the effectiveness of possible termiticides. A technique for breeding the termites is suggested.
M Argoud, J Mocotte, R Sternalsky


Development of marine borers research in Sao Paulo State, Brazil
1985 - IRG/WP 4117
This paper describes some field tests which have been carried on marine sites in Sao Paulo State mainly to investigate the natural resistance of Brazilian woods and the occurrence of marine borers. Some laboratory breeding tests which are being developed are also describe
G A C Lopez


The effects of density on vertical variation of permeability of Sitka spruce within tree
2000 - IRG/WP 00-40156
Tree improvement of Sitka spruce is a combination of silviculture and tree breeding aimed at producing higher quality products including increased growth rate and timber yield, and wood density. It is useful to know annual ring structure and density distribution when studying the quality of wood, grading it, or determining how the wood structure affects residual flow in softwoods. Since density is a factor under genetic control, the study in this article details the effects of density on longitudinal and radial permeability of Sitka spruce from base to apex. Comparison of overall means of both longitudinal and radial void volume filled (%) suggest that longitudinal permeabilities were almost the mirror image of those for the radial permeability along the tree trunk.
I Usta.


Report on Sub-group 5 in Raleigh, 6 May 1980
1980 - IRG/WP 1123
S Cymorek


Investigations on the life cycle and nutrition of Criocephalus rusticus L
1974 - IRG/WP 127
The longhorn beetle Criocephalus rusticus L or Arhopalus rusticus (L) is widely distributed in Europe and Asia. It attacks softwoods. The primary host trees are pines, ie freshly felled, unbarked logs, dying standing trees and stumps. After feeding under the bark the larvae enter the sapwood and also the heartwood. Timber to be used for building purposes may be rendered useless by their tunnelling activity. Occasionally some larvae survive in the wood in situ and emerge as beetles. The thus caused pattern of damage is sometimes mistaken for that caused by the house longhorn beetle Hylotrupes bajulus (L). In the Bundesanstalt für Materialprüfung (BAM) a culture of Criocephalus rusticus has been maintained for several years. It was based on one single female. This culture offered the possibility of following the life cycle of the insect quite closely. Research was concentrated on three main aspects, ie on the timber species which are most suitable for the development of the insect, on the influence of the wood moisture content on its development and on the environmental factors inducing pupation. Moreover some studies were made to find out whether turpentine oil which - as an essential oil contains many wood extractives of pine - has an attracting effect on the beetles for oviposition or on the recently hatched larvae. Present knowledge of Criocephalus rusticus is primarily based on numerous individual observations of different authors. Data on this beetle and related species are therefore often found in shorter contributions. Moreover Criocephalus rusticus is mentioned in more comprehensive works on longhorn beetles or on wood pests. In 1954 and 1958 this species was studied in more detail by J DOMINIK. The species Criocephalus tristis F (= Arhopalus ferus Mulsant or Criocephalus polonicus Motsch) was investigated by H R WALLACE in 1954. The appearance and biology of this species is very similar to Criocephalus rusticus, the regions of distribution of these two species overlap, but Criocephalus tristis is still distributed farther south than Criocephalus rusticus. As Criocephalus tristis was imported into New Zealand in about 1962 several investigations were made there - although up to this time not very comprehensive ones (G P HOSKING, 1970). The results obtained in the BAM will be presented in the journal "Materials and Organisms" after a complete evaluation of the test results and considering the available literature. The preliminary results are summarised here.
H Kühne


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 durability which indicates that density might have some influence on durability of these wood species.
S Akhter, K Akhter, S C Das


Moderate temperature fixation of CCA-C
1989 - IRG/WP 3522
Several Canadian treating plants are using moderate temperature (40-60C°) fixation chambers to reduce drippage and leaching from fresh CCA treated wood. In this study, chromium reduction and surface leaching properties of CCA-C treated red pine (Pinus resinosa) pole sections were monitored during exposure to temperatures of 50-60C° and 90-100% RH conditions. Chromium-VI concentration in the absorbed treating solution dropped significantly during the treating cycle to 50-60% of that in the free treating solution. The chromium-VI concentration also dropped with increasing depth in the pole. During the six to 24 hour fixation cycle the Cr-VI concentration dropped steadily especially in the outer layers of the pole, but even after 6 hours, a significant amount of Cr-VI was observed at all measured depths. After 12 hours, Cr-VI was only barely detectable at all depths. The leachate analyses were consistent with the Cr-VI results, indicating reduced but still significant surface losses while Cr-VI could still be detected.
P A Cooper, Y T Ung


On the species problem in Nicobium castaneum (Col., Anobiidae)
1975 - IRG/WP 134
Nicobium castaneum (Oliv.) is one of the most important wood and book worms of the Mediterranean area (eg Portugal) and South Russian. It also occurs in the USA and Japan. A previous paper (Cymorek 1972) left open the question: is Nicobium castaneum one or two species? Nicobium castaneum is currently regarded as forming two varieties or sub-species - sub-specific taxa which are rarely well defined in the Coleoptera. When dealing with an insect of economic relevance, the exact determination of its status is necessary for the best application of control measures. The subject is also of interest for the taxonomy and systematics of the Anobiidae. First cross breeding results lead to the impression that probably a single species was concerned. Trials of the fertility of hybrid populations were planned to test this opinion. Results are given below.
S Cymorek


Evaluation of the efficiency of industrial kiln type CCA fixation chambers
1996 - IRG/WP 96-40063
Six commercial CCA treating plants in Canada were assessed for the fixation efficiency of their hot air fixation chambers. The wood temperature was measured with thermocouples over the fixation period at different locations in the chamber and at the end of the fixation cycle, the degree of chromium fixation was determined by a boring leaching procedure. There was a great variation in the effectiveness of the chambers, related to the heat transfer efficiency of the kilns. Both an adequate steam supply and efficient air circulation are essential to ensure quality fixation in a reasonable time frame. In plants without this, the wood deep in the lumber piles is still in a mainly unfixed state when removed from the fixation chamber. In contrast, for CCA treated wood allowed to fix under ambient temperature conditions, the interior of bulk piled lumber fixes faster than the outer wood or stickered wood. This results from the cooling effect of water evaporation from the exposed lumber as it dries.
A Taylor, P A Cooper


Quantification des émanations de substances dans l'air ambiant a partir des bois traités
1993 - IRG/WP 93-50001-27
Pesticides on wood for the purpose of its protection may evaporate. Eventual toxicity of such emanations justifies risk assessment procedures for indoor air in building. This document describes bench scale tests based on the technique of chambers developped by CTBA/BIOTEC to determine the amount of pesticides and associated substances released to the ambient air. Results obtained with various pesticides are reported. The part played by physico-chemical parameters including formulation is also described. Conclusions are that relevance of risk assessment procedures must pay atention to formulation, wood and in service conditions and that specific models might be necessary.
H Sageot, M Lamour


Genetic Engineering in tree breeding
1998 - IRG/WP 98-10294
The genetic improvement of forest trees by classical breeding is a slow process in comparison with that of annual crops. Tree breeding however is of great importance and has led to trees with better growth characteristics and better disease resistance. An important wood characteristic which has been neglected in breeding programs is wood durability. The durability of the wood will determine for which purpose the wood can be used and this is of great economic value. Genetic engineering can accelerate tree improvement significantly. It allows the modification or addition of a given trait in any tree species. Here, some examples of genetic engineering in trees (mainly poplar species) are given. For instance, transgenic poplar trees that have a modified lignin biosynthesis to improve pulping, are examined in more detail. Furthermore, the possibilities to enhance wood durability by genetic engineering are discussed.
J Van Doorsselaere, H Beeckman, M Van Montagu, W Boerjan


On the possibilities of the use of juvenile hormone in wood protection
1976 - IRG/WP 363
The annual world-wide extent of losses caused by wood-destroying insects in timber in buildings and timberyards is very difficult to estimate. In general exact values are only known in cases of claims for damages from insurance companies or in litigation. At present the best known wood destroying insects in Switzerland are the house longhorn beetle (Hylotrupes bajulus) and the common furniture beetle (Anobium punctatum). With the increasing imports of tropical timber to Switzerland the risk of bringing unknown pests in exotic timber is growing too. One of these pests is the powder post borer, Lyctus brunneus. Principally it is introduced in the wood species obechi and limba from Central African regions. In most cases the logs are processed here, the damage not being noticed at this stage, and the timber used almost exclusively indoors. Within buildings the beetle Lyctus brunneus finds a climate within its biological tolerance. Consequently its destructive power finds its optimum conditions and the damage caused is often considerable. In Germany Lyctus brunneus takes an important place on the scale of the economic important wood destroyers and it is also spreading in Switzerland. For the selection of the test insect for these investigations the afore-mentioned topicality of the beetle and also some technical advantages in working with the insect are decisive, viz: - short life cycle (only 3 months for each generation) - simple breeding methods - the presence of the necessary information on its mode of life. The following short introduction into the biology of the insect Lyctus brunneus, living in wood, is important for the comprehension of the problems arising by experimenting with JHA (juvenile hormone analogues).
P Tscholl


A review of Sitka spruce (Picea sitchensis (Bong.) Carr.) as its Importance and Breeding
2010 - IRG/WP 10-10717
Foresters tend to concentrate on those species which are the easiest to handle silviculturally, and which will produce the greatest volume of generally useful wood in the shortest time. Sitka spruce (Picea sitchensis (Bong.) Carr.), which is a softwood species from the western seaboard of North America with a range extending from southern Alaska to northern California, is one of the pioneer species in tree breeding. This paper therefore presents the major importance of Sitka spruce in forestry based on the genetic variability of the species and its potential serviceability as a wood material.
I Usta, R Despot


Cost effective extension of service life of bridge tie (sleepers) - Effectively applying borate during Boulton conditioning and treatment with copper naphthenate
2014 - IRG/WP 14-30637
Current longevity of creosote treated wooden bridge ties in the South Eastern US is about 15 to 25 years, which is well below of the average service life of 33-50 years of railroad ties. Such short service life increases costs associated with maintenance of railroads including bridge down time for tie replacement as well as the cost for the new ties themselves. Because of this, many railroads are seeking non-wood alternative ties, even at vastly elevated initial cost. The objective of the study was to see if it is possible to apply borate as part of a dual treatment with copper naphthenate, in order to increase the service life of wooden bridge timbers at minimal additional cost. Green hardwood ties were ported, borate treated, and then Boulton treated with copper naphthenate at a commercial tie treatment plant in Pennsylvania. Diffusion of borate within the wood appeared to be significantly enhanced by the elevated temperature and steam generated during the Boulton cycle and subsequent pressure treatment with copper naphthenate. The achieved retention and penetration of borate and copper naphthenate met AWPA standard retentions and AREMA guidelines. The longevity of ties should be significantly increased by protecting the heartwood with disodium octaborate tetrahydrate (DOT) and the sapwood with copper naphthenate. The results suggested that hardwood ties can be successfully treated with borate during a Boulton cycle and should allow the continued effective use of sustainable wooden bridge timbers.
J D Lloyd, T Chambers, J-W Kim


Towards better integration of wood protection in the forestry wood industry chain - a case study on hybrid poplar
2019 - IRG/WP 19-50359
Wood and wood products are limited in service life as in the forest ecosystem trees at end of their life are degraded to re-enter the bio-geochemical cycle. Humans can select wood species with a level of natural durability fit for an envisaged end use. Mainly those applications that require a long service life under conditions that are similar to those at soil level in a forest ecosystem have been the early focus for wood preservation. Testing wood preservatives intended for enhanced performance of wood in soil or water contact was originally based primarily on performance benchmarked with wood species having higher natural durability. Over the last decades, wood protection has altered focus towards end uses out of ground contact even sometimes specifically for interior applications. Parallel to this evolution wood modification treatments were assessed also to improve general performance of wood species. Besides an increased potential for using low durability wood species, mainly dimensional stability related properties were envisaged. The forestry-wood chain has evolved in the second half of last century from mainly production based strategies to policies based on ecosystem services in a sustainability framework. Today forests are intended to provide services for the bio-economy, human health, biodiversity and climate control. An increased need for more renewable resources both for material and energy use has initiated extra focus on the potential to produce more lignocellulosic biomass, in short to increase wood production. Forest types identified as primary forest as well as (semi)-natural forests require conservation measures limiting the option to increase volume that can be harvested. One option is to provide in complementary production in planted forests. Both forestry and agriculture can take part in this. The cultivation of poplar hybrids in the temperate regions is a key option for the current and future bio-economy. These fast-growing trees are producing lightweight hardwood material with a low natural durability. All wood protection methods are of interest to be evaluated for this wood resource, making it suitable even for high quality applications. Poplar, for many reasons, has been nominated as hardwood with the best potential to perform similarly as softwoods for applications in wood construction. Benchmarking with wood species like spruce is relevant for several engineered wood products like plywood, LVL and even CLT. Wood treatments to increase durability have also evolved from traditional wood preservation towards modification techniques such as thermally modified timber depending on the performance required or fit for purpose in relation to a specific combination of use class and service life.
J Van Acker