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Seasonal response of feeding, differentiation, and growth in the eastern subterranean termite Reticulitermes flavipes (Kollar) in Wisconsin
2007 - IRG/WP 07-10604
In termites, differentiation plasticity in undifferentiated Reticulitermes progresses with growth stages from larvae to workers, which may then differentiate into soldiers, winged nymphs, or neotenics. Although studies have been done on seasonality of the termite life cycle, data appears to vary from location to location. Reticulitermes populations in Wisconsin appear to behave slightly differentl...
R A Arango, F Green III, G R Esenther


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


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...
I Usta


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...
I Usta.


Seasonal effects of the field evaluation on wood preservatives against mold fungi
1996 - IRG/WP 96-20087
For the purpose of the amelioration of field test methods, commercial preservatives against mold fungi were tested under two different seasons, in winter and in summer. The specimens were bundled and set over the water bath and all these systems were covered with plastic film. At top of the system under film, black films for regeneration of sunlight were put in, and windows for changing air were r...
K Suzuki, Y Sugai, K Ryugo, D Watanabe


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


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


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 ...
J Norton


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...
D Dirol


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


Some recent studies on the marine wood-borers of the west coast of India
1982 - IRG/WP 486
Occurrence and distribution of marine wood-borers along the west coast of India from Mangalore to Kandla are presented together with the distribution pattern of all the molluscan and crustacean wood-borers so far reported from India coasts. The survey, conducted for the first time along this coast, revealed the presence of 14 species of Teredinidae, 2 species of Pholadidae, 3 species and one varie...
L N Santhakumaran


Observations on the morphology, ecology and biology of Xylophaga dorsalis (Turton) (Mollusca: Xylophagainae) in the Trondheimsfjord (Western Norway)
1981 - IRG/WP 475
The paper deals with various aspects of the systematics, ecology and biology of the little known pholad wood-borer, Xylophaga dorsalis (Turton) of the Trondheimsfjord (Western Norway). Diagnostic characters of the species have been given based on examination of fresh living specimens and accommodating the several morphological variations. A key to the identification of Norwegian species of Xylopha...
L N Santhakumaran


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...
J Bjurman


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


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


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


Observations on the morphology, ecology and biology of Xylophaga dorsalis (Turton) (Mollusca: Xylophagainae) in the Trondheimsfjord (Western Norway)
1981 - IRG/WP 466
The paper deals with the various aspects of the systematics, ecology and biology of the little known pholad wood-borer, Xyophaga dorsalis (Turton) of the Trondheimsfjord (Western Norway). Diagnostic characters of the species have been given, based on examination of fresh living specimens and accomodating the several morphological variations. A key to the identification of Norwegian species of Xylo...
L N Santhakumaran


Variation in field test performance of untreated and CCA-treated lesser-known Surinamese wood species
2000 - IRG/WP 00-20213
In Suriname three different field test sites have been used to verify the biological durability of CCA-treated wood and a range of wood species including lesser-known and lesser-used wood species. In total 37 tropical wood species were tested untreated and for 17 of the less durable species CCA-treatments were included as well. Although the three sites are located in the tropical region they diffe...
J Van Acker, M Stevens, L Comvalius


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