Your search resulted in 43 documents. Displaying 25 entries per page.
Decay resistance of Scots pine (Pinus sylvestris) heartwood against brown rot
2002 - IRG/WP 02-10433
Natural decay resistance of wood is mainly restricted in the heartwood and based on wood microstructure and chemical composition. The genetic variation in the durability of Scots pine (Pinus sylvestris L.) wood against decay and the relationship between resistance and chemical composition was studied. The laboratory tests of 6 and 8 weeks were carried out with a brown rot fungus Coniophora puteana...
H Viitanen, A M Harju, P Kainulainen, M Venäläinen
Decay resistance of Siberian larch wood against brown rot fungi - Part 2. The effect of genetic variation
1998 - IRG/WP 98-10287
Wood natural decay resistance is mainly restricted in the heartwood part of tree and based on wood microstructure and chemical composition. However, the variation of decay resistant in different wood species is vide and the effect of genotype on decay resistance of Siberian larch wood grown in Finland is not known. The aim of this work was to find out the variation on decay resistance of Siberian ...
H Viitanen, L Paajanen, T Nikkanen, P Velling
Decay resistance of Siberian larch wood against brown rot fungus. - Part 3. The variation between plus trees and their grafted clones
2000 - IRG/WP 00-10350
The aim of the study was to estimate the variation in the decay resistance of Siberian larch (Larix sibirica Ledeb.) wood using mature plus trees and their grafted clones. Samples were collected with an increment core borer from 11 original plus trees and their 25-year-old grafted seed orchard clones. A typical brown rot fungus, Coniophora puteana (Schum. ex Fr.) Karst. (BAM Ebw. 15), was used as ...
H Viitanen, L Paajanen, M Venäläinen, A Harju, P Velling
Distribution and genetic variation of Reticulitermes (Isoptera: Rhinotermitidae) in Portugal
2006 - IRG/WP 06-10581
The genus Reticulitermes has a Holartic distribution and is widely represented in southern Europe. It is established in Portugal, across the full range of ambient environmental conditions, using different types of wood resources, as available, and nesting ubiquitously in many types of soil. Sequencing of part of the mtDNA COII gene revealed that all the specimens sampled on a N-S transect of the c...
T Nobre, L Nunes, P Eggleton, D E Bignell
Is there a role for termite alates in colony expansion in Wisconsin?
2014 - IRG/WP 14-10820
Termite colonies in Wisconsin tend to be large and widely spread out geographically, and separated by distances up to 1342km. We recently completed a study to determine the genetic diversity and population substructure of thirteen existing colonies of Reticulitermes flavipes using amplified fragment length polymorphism to determine patterns of termite dispersal in Wisconsin. Measures of inbreedin...
F Green III, R A Arango, G R Esenther, T G Shelton
Successive collections of Basidiospores from wood decay fungi (in vitro) show variation in germination levels on common media
1978 - IRG/WP 191
In the course of various preliminary experiments in which spore germination levels of 6 decay fungi on malt and water agar were recorded as controls, it was noted that one could not reliably obtain an expected level of spore germination for any particular fungus. Inconsistent 'control' spore germination levels of a fungus greatly complicates large scale experiments in which compa...
E L Schmidt, D W French
An attempt to evaluate wood resistance against fungal decay in non-sterile conditions by measuring the variation of resistance to bending test
1988 - IRG/WP 2308
The main object of this work was to determine the variation of strength on large test specimens of wood (800 x 45 x 45 mm³) when exposed to accelerated fungal attacks close to natural conditions, out of test vessels. The modulus of elasticity (MOE) and the modulus of rupture (MOR) have been assessed. Thereby, the natural resistance of the wood species to fungal decay, the efficiency of preservati...
L N Trong
What can DNA fingerprinting, aggression tests and morphometry contribute to the identification of colonies of the Formosan subterranean termite
2000 - IRG/WP 00-10371
Multilocus DNA fingerprinting, aggression tests and morphometry were compared to evaluate their potential for the identification of colonies of the Formosan subterranean termite, Coptotermes formosanus (Isoptera: Rhinotermitidae) in Hawaii. DNA fingerprinting separates the termites from all studied collection sites. Since the genetic similarity between termites from different collection sites lies...
C Husseneder, J K Grace
Analysing the characteristic role of moisture content for drying and fluid flow in Sitka spruce. - Part 1: The drying process of sapwood and heartwood of two different thickness of Sitka spruce using a kiln. - Part 2: Effects of moisture content on longitudinal permeability of Sitka spruce in vertical variation of the tree
2000 - IRG/WP 00-40173
The characteristic role of the moisture content in Sitka spruce (Picea sitchensis (Bong.) Carr.) that grown in the United Kingdom was examined by this study on the basis of (1) the reduction of moisture content in two different thickness of sapwood and heartwood by kiln drying process, and (2) the effects of moisture content to the longitudinal void volume filled of tanalith-C by the full-cell pro...
Differences in feeding activity among colonies of Formosan subterranean termite Coptotermes formosanus Shiraki
1983 - IRG/WP 1202
Feeding activities of 7 colonies of the Formosan subterranean termite, Coptotermes formosanus Shiraki, were examined. Wood-consumption rates among colonies differed significantly, ranging from 23.80-78.48 mg/g/day. This large intraspecific variation raised a question of whether differences in feeding activity reported for other termite species were due to interspecific differences. When rates were...
N-Y Su, J P La Fage
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...
The variation in electrical resistance in the CCA-treated wood during the fixation
1989 - IRG/WP 3554
The curve commonly used in Scandinavia for describing the fixation period at different temperatures for CCA-impregnated wood is based on investigation by Dahlgren on the pH-variations in a mixture of sawdust and preservative solution. As far as we know there is no such investigation on solid wood. We have therefore measured the electrical resistance in CCA-treated solid wood to see if this will di...
F G Evans, B Nossen
Variation in Canadian bluestain fungi: Tolerance to DDAC and DOT
1999 - IRG/WP 99-10303
Bluestain in Canadian wood products results in significant and unpredictable losses each year. In order to develop rational methods to eliminate or reduce the sapstain problem, a more complete knowledge of the causal organisms must be gained. This includes a knowledge of the variability in tolerance of different fungal species and strains to commercially used chemicals. In British Columbia, the ma...
J Dubois, A Byrne, J E Clark, A Uzunovic
Physical properties variation of sound and top dying affected sundriwood (Heritiera fomes) in mangrove forest of Bangladesh
2004 - IRG/WP 04-10504
Top dying of sundri (Heritiera fomes Buch.-Ham.) in the Sundarbans is considered to be the most severe of all the diseases of tree crops in Bangladesh. The wood samples from sound, moderately affected and severely affected sundri trees from three different tree heights for every individual test were collected and their respective physical properties were examined to make a comparison. It was found...
S C Ghosh, A K M A Bosunia, M A Islam, A K Lahiry
Sampling variation in a copper chrome arsenic treated power transmission pole
1990 - IRG/WP 2351
The Queensland Forest Service routinely samples poles treated at all treatment plants throughout the State. Each treatment plant is issued with a Certificate of Registration and the accompanying documents list the different levels of preservative retention required for performance in various service conditions. The posted levels represent the.minimum permissible, and it is to these concentrations ...
Variation in infection rates of blue-stain, mould and white rot tropical fungi on mixed light Malaysian woods
2000 - IRG/WP 00-10334
The modified 3-week FRIM laboratory method for screening of anti-sapstain formulations against three representative tropical fungi causing blue-stain (Botryodiplodia theobromae), mould (Paecilomyces variotii) and white rot (Schizophyllum commune) infection of sapwood species was used to examine the relative resistance of the sapwood of eight mixed light Malaysian woods, Scots pine (Pinus sylvestri...
A H H Wong, S Ahmad
Investigation on different variation factors in the results of mycological test and means to reduce and avoid them
1986 - IRG/WP 2264
In order to clarify the causes of the dispersion observed in the results obtained with mycological tests made in accordance with standard EN-113, different factors assumed to be sources of the variations were studied. These included the moisture content of the test samples during the test, the influence of certain technological properties of the wood, the virulence of the fungus strains, the metho...
Natural Durability of Tropical Species – Variations and Prospects
2005 - IRG/WP 05-10568
The tropical timber resources of the world play an unequivocal role in economic development of both the tropical timber producing and importing regions. This paper describes natural durability as an important and preferred wood quality of tropical species of the world with emphasis on Malaysian hardwoods, the link between various aspects of tropical hardwood durability, hardwood utilization and bi...
A H H Wong, Yoon Soo Kim, A P Singh, Wang Choon Ling
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
Variation of natural durability of sugi (Cryptomeria japonica) wood in 15 clones examined by decay test (Preliminary report)
2004 - IRG/WP 04-10526
Natural durability of wood in 27 trees from 15 clones of sugi (Cryptomeria japonica)　 was investigated by an accelerated decay test. Thirty years old trees were collected from a clonal trial in Ibaraki prefecture, Japan. Natural durability is usually evaluated in heartwood. Mass losses of heartwood caused by a brown rot decay fungus, Fomitopsis palustris and a white rot decay fungus, Py...
K Yamamoto, A Tamura, R Nakada
Effect of humidity fluctuations on mould growth on pine wood
1989 - IRG/WP 1412
Most studies on mould development on wood material have been made at constant moisture conditions during the experimental period. As a consequence of such studies, a maximum permittable humidity level to avoid mould problems in wood constructions has been recommended. In the practical situation, the constructions are seldom subject to constant humidity or temperature. In the present paper, we repo...
Variation in natural durability of British grown Douglas fir ((Pseudotsuga menziesii (Mirb.) Franco). Part II. Effect of extractive contents and taxifolin
2002 - IRG/WP 02-10446
The previous paper (Part I: Effect of density and growth rate) described the variation in natural durability of 4 Douglas fir (DF) seed origins (Darrington, J. Landing, Naselle and Hawkinsville) in a pure culture decay test and fungal cellar test. The pure culture tests were performed against two brown rot fungi (Coniophora puteana and Postia placenta). In the fungal cellar test soft rot was the p...
S Akhter, M D C Hale
Aureobasidium or Hormonema? A Genetic Approach.
2004 - IRG/WP 04-10529
Aureobasidium pullulans is the main organism causing disfigurement of coatings on wood and the surface of exposed timber. This disfigurement of timber in-service is referred to as “bluestain in-service”. A. pullulans is also associated with the sapstaining of dead wood in the forest and in-service. A. pullulans is noted for its highly variable growth forms (polymorphisms). This variability pre...
M J Ray, D J Dickinson, M Buck
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 wh...
J Van Doorsselaere, H Beeckman, M Van Montagu, W Boerjan
Variation in biological performance of CCA caised by preservative application method
1996 - IRG/WP 96-40072
A series of laboratory studies to investigate the influence of treatment application method on CCA performance in Cosican pine has been completed. Biological decay tests, such as serial exposures, were used to induce decay in wood at preservative retentions of up to 10 kg/m³ CCA salts. Significant differences in performance of the preservative against either brown, white or soft rot decay fungi w...
P R Newman, R J Murphy