Your search resulted in 17 documents.
Über den Nagekäfer Oligomerus ptilinoides (Wollaston), Col., Anobiidae: Verbreitung und Einschleppung, Bestimmung, Lebens- beziehungen und Befallsmerkmale mit Vergleichen zu Nicobium
1980 - IRG/WP 1102
Oligomerus ptilinoides occurs in the Mediterranian and Black-sea area, in North-Africa and Asia minor as an important pest causing severe damage to dry wood. By travelling, by the immigration of people from south to north, and by accidental introductions the species tends to establish itself north of the Alps. Severe damage has recently been observed in two museums. An account is given of aspects of taxonomy, the pattern of attack compared with that of Nicobium hirtum and Nicobium castaneum, of the anatomy of the larvae, on symbiosis, and on behavioural features of the beetles.
CCA component distribution in the heartwood of treated lodgepole pine and white spruce
1998 - IRG/WP 98-30173
As part of a comprehensive study on the influence of drying on heartwood permeability, the distribution of copper, chromium and arsenic (CCA) in lodgepole pine (Pinus contorta Dougl.) and white spruce (Picea glauca (Moench) Voss.) heartwood was examined with light microscopy. Stained microtomed sections were examined to determine the penetration pathway for the CCA. The microscopic observations revealed clear differences in the distribution of the various components in the various cells in the CCA treated wood, particularly those associated with ray cells and resin canals. At the limit of CCA penetration, it was clear from the intensities of the staining in the section, that the ray cells and resin canals were primary avenues solution penetration to the tracheids. Higher levels of components of CCA were observed associated with the resin canals and ray cells than with the tracheids.
Y An, J N R Ruddick, P I Morris
The effects of heat treatment on anatomical changes of beech wood
2004 - IRG/WP 04-40284
The effects of heat treatment on anatomical changes of beech wood (Fagus orientalis) naturally grown and intensively used in forest products industry in Turkey were studied. The wood samples were cut into 2x2x3 cm and than conditioned at 25 °C and 65 % relative humidity for 3 weeks. Heat treatment was than applied to the wood samples at four different temperatures (130 °C, 150 °C, 180 °C and 200 °C) and three different durations (2 h and 10 h) under air atmospheres. The anatomical changes were determined for each heat treatment variation.
Ü C Yildiz, Z Gerçek, B Serdar, S Yildiz, E D Gezer, E Dizman, A Temiz
Soft rot decay of Eucalyptus maculata Hook. in different soils from Queensland, Australia
1980 - IRG/WP 1113
In the present work, different Queensland soils were chosen and their gross effects on the decay of treated and untreated Eucalyptus maculata examined. The soils were also amended with various levels of phosphate to study the response of the wood decay mycota to an increasing supply of this nutrient. Phosphate amendment was chosen because of the wide-scale use of superphosphate on Queensland soils and the importance of inorganic phosphate in the carbohydrate metabolism of microorganisms.
L E Leightley, I W Russell
Treatability problems - Relationships between anatomy, chemical composition and treatability
2001 - IRG/WP 01-40213
This report documents the results of phase 1 and 2 of a 3-phase research program. In phase 1, two hundred and fifty-six (256) Southern pine (pinus spp.) nominal 2 x 6's (38 mm x 140 mm) from a single mill in Georgia (southeastern US) were evaluated for treatability with CCA preservative. After treatment, 128 pieces representing a broad range of treatment characteristics were selected and more fully evaluated for anatomical and chemical composition. No direct correlation was noted between CCA treatability and any of the anatomical characteristics evaluated in this study. Neither did a direct correlation between chemical composition and treatability seem to exist. The pit tori of all pits evaluated in this study were aspirated against the pit wall for this difficult to treat Southern pine lumber. This pit aspiration might have resulted from pre-treatment kiln drying. Later reductions in kiln temperature and increased kiln humidity (i.e., lowered wet-bulb depression temperature) reportedly resulted in improved treatability. In Phase 2, a methodology was developed to assess treatability after 3 treating schedules and then compare those results to permeability measurements and anatomical characteristics of matched material from 7 growth regions.
J E Winandy, F Green III, D Keefe
Cellular and fractural failure after supercritical fluid impregnation of four wood species
2004 - IRG/WP 04-10503
Supercritical fluids (SCFs) have been investigated for delivering biocides into sawn wood. Pressure differentials during treatment may exceed the compressive or tensile strength perpendicular to grain, creating a potential for transverse deformations that exceed elastic strain limits. Wood treated by SCF processing with CO2, a potential biocide carrier, was inspected macroscopically and microscopically. Both cell wall damage and smooth fracture surfaces appeared in the cellular structure. Damage was related to the rates of pressurization and venting and appeared to be species-specific. Cell walls were damaged during pressurization, whereas fracture damage occurred during venting. Specimen dimensions, permeability and anatomical structure are critical variables in developing SCF processes for biocide treatment of wood and wood-based products.
M E Anderson, R J Leichti, J J Morrell
Rubberwood anatomy and its influence on gaseous permeabilit
1993 - IRG/WP 93-40005
The anatomical structure in several rubberwood (Hevea brasiliensis Muell. - Arg.) samples was examined by use of a Cambridge Stereoscan 600 scanning electron microscope. A series of electron micrographs is presented which illustrate those features anticipated as having an influence on permeability. A series of gas permeability experiments were performed on oven dried samples of rubberwood to determine the relative longitudinal, radial and tangential gaseous permeabilities. The results indicated that the permeability in the different directions examined was in the descending order longitudinal > tangential > radial. Graphs of specific flow rate as a function of mean pressure demonstrated that flow was essentially through one component in the longitudinal direction whereas in the tangential and radial directions it was through more than one.
A J Pendlebury, J A Petty
On the nature of the tertiary wall in wood cells. Summary of lecture given at 9th Annual Meeting, Noordwijk-aan-Zee, Holland
1977 - IRG/WP 169
During recent discussions on the possible causes of failure of treated hardwood species by soft rot fungi, the uneven micro distribution of toxic components was found to be of importance; this might be attributed to a restricted diffusion of the preservative from the cell lumina into the cell wall.·In this context, the nature of the tertiary wall as the inner lining of wood cells merits special attention. In the following, the present knowledge concerning the wall layer is summarized.
Wood detection by the marine isopod Limnoria.markup
1995 - IRG/WP 95-10134
The search for alternative control methods for Limnoria, should perhaps focus on the most vulnerable stage during the isopod life cycle - during dispersal when adulls leave their tunnels to find new wood. Dispersal is known to be triggered by environmental conditions, although how Limnoria locate fresh wood is unknown. Literature available on Limnoria dispersal, their sensory capabilities during dispersal and colonisation of new wood, suggests that chemoreceptors and mechanoreceptors are the most likely sense organs used during dispersal and wood attack. Evidence for the detection of wood by Limnoria using distance chemoreception is lacking, though there is some evidence for contact chemoreception. A preliminary research programme involving behaviour experiments, light microscopy, scanning and transmission electron microscopy to determine how Limnoria detect wood is presented. Behaviour results show that antenna 1 and antenna 2 are used in functionally different ways, suggesting each pair of antennae are responsible for a different sensory modality. Contact chemoreceptors on the second antennae and olfactory sense organs on the first antennae may be responsible for detecting wood. Both the uropods and ventral edge of Limnoria telson are in constant contact with the surface of wood during crawling and are therefore ideal locations for sense organs.
S M Henderson, S M Cragg, A J Pitman
The functional anatomy of the digestive caecae and gut residence times for the marine wood borer Limnoria (Crustacea: Isopoda)
1997 - IRG/WP 97-10204
A scanning and transmission electron microscope study of the digestive caecae of the marine wood boring isopods Limnoria tripunctata and Limnoria quadripunctata, was undertaken. Two cell types were identified, containing structures indicative of absorption, secretion and storage. Cell types were distinguished according to size, the largest cell type having a large free surface area, a well developed microvillous border and a cytoplasm containing both iron and what were believed to be proteinaceous granules. The small cells possessed endoplasmic reticulum and lipid granules. This study suggests that large cells were responsible for absorption and storage of iron, whereas the small cells were secretory and capable of storing lipid. Residence time for wood in the gut was determined to be approximately two hours for both Limnoria tripunctata and Limnoria quadripunctata. This rapid gut transit time is relatively short compared to other cellulose digesters, suggesting that Limnoria is an inefficient digester of wood.
C Wykes, S M Cragg, A J Pitman
Wood printing plates from the Dürer era – species identification and anatomical study
2007 - IRG/WP 07-20364
Anatomical examinations serve to answer questions regarding the artistic technique and authenticity of art objects made of wood. The wood of 28 printing plates from the 15th and 16th centuries from the Berlin Kupferstichkabinett were investigated. Seven of these which date from the Dürer era (Albrecht Dürer, 1471-1528) were examined in more detail. With one exception, the plates from the Dürer era were made of wood of the family Rosaceae, subfamily Pomoideae. The greatest similarity was found with the genera Pyrus, Malus, and Crataegus. Pyrus communis is especially suitable for the manufacture of printing plates because of its uniform texture, high density, and hardness. Wood from the family Betulaceae, genus Alnus, was used for only one of the plates.
M Penkuhn, W Unger
European House Borer Hylotrupes bajulus Linnaeus in Western Australia: the anatomy of an eradication program
2009 - IRG/WP 09-20403
In January 2004, European house borer (EHB) Hylotrupes bajulus Linnaeus was detected in Perth, Western Australia. A containment program was set up and expanded to a full eradication campaign in 2008. The program is projected to eradicate EHB by 2021. This paper describes research work and assumptions on the biology and behaviour of EHB in Western Australia, surveillance and control methods, community engagement and regulatory controls on movement and use of pine, and the response of industries producing and using pine timber. To the end of 2008 less than 1% of detected infestations have been in timber in service, while 99% of infestations occur in dead pine trees. Destruction of infested and susceptible pine trees and wood not in service is the main control measure. The aim is to control EHB in the external environment before it makes a transition to timber in service in the built environment. Control methods differ between urban environments and pine plantations.
M Grimm, R J Cunningham, M Castalanelli, D Collins, L Vagg
Comparative Study of Heat Treatment of Beech Wood in Hot Water and Steam Medium
2010 - IRG/WP 10-40536
Heat treatment of wood is an effective method to improve the dimensional stability and durability against biodegradation. Heat treatments of beech wood in 2 different mediums (hot water and steam) in 180ºC were compared in physical, mechanical and anatomical properties. Mass loss in hydrothermally treated wood was higher than hygrothermally treated samples. Mechanical properties (MOR, MOE and CS) were decreased in both mediums, but strength loss was higher for hygrothermal treated samples. Anatomical changes were investigated by means of a light microscopic analysis. Beech was sensitive to collapse of the vessels in both mediums. In treated beech, radial cracks were observed near the rays both in hydro and hygrothermal treatments. Depletion of extractives on the cell walls and deformation of libriform fibers near the vessels were also observed.
A Talaei, K Yaghoobi, A N Karimi
A guideline for sorting easy to impregnate Scots pine sapwood based on three treatability studies from Northern Europe
2014 - IRG/WP 14-40669
Scots pine sapwood is generally considered an easy to impregnate wood species, though it reportedly faces challenges towards a homogeneous impregnation and large variations in treatability are reported for the material. This study comprises the results of three treatability tests that were performed on Scots pine (Pinus sylvestris) sapwood. The material impregnated was originated from a large area in northern Europe, covering seven different countries. In all tests a furfuryl alcohol mixture served as a model impregnation agent for treatments with larger molecule size. The factors that influenced the treatability were investigated. Geographic origin, climate, sample position within the stand, growth conditions in the forest, annual increments, wood and anatomical properties were all found to have a significant influence on the treatability. Derived from these factors a guideline for sorting easier to impregnate Scots pine sapwood is presented in this paper.
K Zimmer, E Larnøy, A Treu
Impact of early lignification of ray parenchyma cells on the treatability of Scots pine sapwood
2015 - IRG/WP 15-40706
The wood anatomy of Scots pine sapwood can influence its treatability. A microscopic analysis on the wood material from four different stands in Northern Europe was performed using tangential sections from the outer part of Scots pine sapwood. Single correlations of the ray composition and lignification state of the ray parenchyma showed the influence of these factors on radial penetration depth and the ratio of filling. Early lignification was negatively correlated with radial penetration depth and ratio of filling. The study shows that ray composition and lignification of ray parenchyma cells are important contributors to fluid flow in radial direction.
K Zimmer, A Treu
Creosote leaching from timber bridges in Norway – a practical classification approach
2016 - IRG/WP 16-40744
Creosote is widely used as a wood preservative for highway timber bridges in Norway. However, excessive creosote leaching at various highway timber bridge sites leads to a bad reputation for the use of creosote treated timber constructions and the use of wood in general. Macro- and micro anatomical factors such as amount of heartwood, annual ring width, annual ring orientation, ray- height and composition and resin canal area were investigated in order to classify seven timber bridges in Norway into leaching- and non-leaching bridges. With three anatomical factors a classification into leaching and non-leaching was possible for two discriminant categories based on observations on wood core samples and on entire bridges. The amount of heartwood content dominated the influencing factors, even obscuring the significance of other factors.
A Treu, K Zimmer
Underground timber constructions from the First World War are well preserved after 100 years
2017 - IRG/WP 17-10897
During the Great War or World War I many underground constructions have been built for protection from shelling. They were an important part of the trench warfare as they were used as an area to rest and carry out other activities such as eating. They would usually range in size from smaller constructions that could hold several men to larger entities that could hold thousands of soldiers. In the context of tunnel warfare the construction of underground facilities was very extensive. About 180 dugout sites have been located in the Ypres Salient and since the 1990s some of them were entered (Doyle et al. 2002, 2005). During use these dugouts which are typically timber based tunnels were kept dry, however got fully submerged when no longer in use. These wooden constructions remained under groundwater level and are very well preserved after approximately 100 years. Several of these constructions have been documented and one specific one is very much highlighted in 2017. As the ‘Zonnebeke Church Dugout’ is intended to open up for the public for some months and this construction was checked on different parameters. Wood species identification confirmed the considerable presence of wood from overseas origin, here Jack pine (Pinus banksiana). Although several low durability wood species have been used the decay rate found on the material is minimal and structural integrity analysis allows to ensure safe passage for visitors to the dugout.
J Van Acker, I De Windt, K Haneca, H Beeckman, F Claeys, S Vandenbussche, J Vandewalle, N Robeyst, A Willems