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Performance of surface-treated hardwoods and softwoods out of ground contact
1990 - IRG/WP 3592
A number of fungicides were tested as brush treatments for protection of southern pine, Douglas-fir, maple, and red oak against decay above ground. Cross-brace and L-joint test units were treated just before assembly and exposed from 3-10 years. Untreated Douglas-fir cross-brace units were not decayed at either the Mississippi or Madison, WI, site. Untreated red oak cross-brace units were not decayed at the Madison site. The two hardwood species were more difficult to protect from decay than the softwood species. Decay development in maple cross-brace units was considerably slowed by several of the treatments but none of the treatments provided complete protection from decay during the 9 or 10 years exposure in Mississippi. Most of the treatments did not reduce decay development in red oak cross-brace units. Many treatments protected pine cross-brace units. The L-joints were exposed for only 3-4 years, but appear more difficult to protect from decay than the cross-brace units.
T L Highley


Estimation of effective diffusion path lengths in wood by swelling studies
1989 - IRG/WP 3524
The effective average distance that a solute must diffuse to penetrate the cell wall matrix following pressure treatment is estimated from the rate of swelling of wood, vacuum treated with water. It is assumed that the diffusion paths are similar for water and a solute such as a wood preservative component. Since bound water diffusion coefficients for water in wood have been estimated by others, the effective path lengths (Le) can be estimated. Effective average path lengths are estimated for red pine (Pinus resinosa), Southern yellow pine (Pinus sp), trembling aspen (Populus tremuloides) and soft maple (Acer rubra) sapwood and red oak (Quercus rubra) heartwood samples. The estimated path lengths are shortest for the softwoods, and longest for the ring porous oak. The results reflect the different patterns of cell penetration and different densities of the wood species.
P A Cooper, R Churma


The effect of creosote and Basilit on the boards of 4 wood species against destructive fungi in Northern Iran
1989 - IRG/WP 3555
The results of the experiments conducted on the boards of maple, hornbeam, alder and beech, show that under the humid and moderate climate condition of Northern Iran, after 30 months, the witness samples were about 10% destructed by fungi, especially by Schyzophyllum commune and Coriolus versicolor. The impregnated samples by Creosote Basilite using Rueping and Bethell methods, were quite intact. There was no difference between these two chemicals. Among destructed boards, maple and hornbeam containing the most sugar and starch materials are more senitive than beech and alder. Until 50% destruction of witness samples, the experiments will follow up.
D Parsapajouh


Probing red maple pit membrane pore size at FSP and OD using polystyrene macromolecules
2001 - IRG/WP 01-40217
A modified solute exclusion technique was used to pressure impregnate a polystyrene molecular weight (MW) series dissolved in styrene into red maple samples at approximately the fiber saturation point (FSP) and oven dry (OD). Radial penetration was less than tangential and FSP less than OD. There was a marked penetration change with MW in the tangential direction, although there appeared to be a slight decrease in FSP penetration at the higher MW tested.
A Omidvar, M H Schneider, A R P Van Heiningen


Effect of wood species on decomposition efficiency of metham sodium
1992 - IRG/WP 92-3699
The effect of wood species and temperature on efficiency of metham sodium (32.1% sodium N-methyldithiocarbamate) decomposition to methylisothiocyanate (MITC) was investigated on 10 hardwoods and 9 conifers over a 144 hour period. Gas chromatographic analyses of headspace samples and ethyl acetate extracts of the wood revealed that decomposition never approached the theoretical decomposition efficiency (40%). Decomposition was generally better with hardwoods and at higher temperatures, although there were exceptions with some species. The results suggest that there is some potential for improving the performance of metham sodium through the use of additives which enhance decomposition efficiency.
J J Morrell


Durability of five wood species against Coriolus versicolor
1992 - IRG/WP 92-1578
The durability of following five wood species Zelkova carpinifolia, Ulmus glabra, Carpinus betulus, Acer trauvetteri and Pterocarya fraxinifolia were studied against Coriolus versicolor under laboratory conditions according to DIN 52176 standards. Zelkova caprinifolia shows a reduction in weight of 2.19%, Ulmus glabra 41.69%, Carpinus betulus 45.64%, Acer trauvetteri 53.05%, and Pterocarya fraxinifolia 43.08%. There was a negative correlation between decay and amount of extractive materials for all species except Pterocarya fraxinifolia.
S M Kazemi


Efficacy of waterborne copper naphthenate as preservative for northern hardwood species
1995 - IRG/WP 95-30091
Northern red oak (Quercus rubra) and red maple (Acer rubrum) cubes pressure treated with waterborne formulation of copper naphthenate were evaluated for resistance to attack by brown fungi Gloeophyllum trabeum (Pers. ex Fr.) Murr. (Madison 617 ATCC 11539) and Poria placenta (Fr.) Cooke (Madison 698, ATCC 11538), white rot fungi Trametes versicolor (L. ex Fr.) Pilat (R-105 from Jeff Morrell), Irpex lacteus Fries (FP-105915 from Jeff Morrell) and Pleurotus ostreatus (Jacq. ex Fr.) Kummer (ATCC 32237), and soft rot Chaetomium globosum (ATCC 34152) and Phialophoria sp. (from Dr. B. Goodell, University of Maine). Wood samples measuring 19 x 19 x 19 mm³ were pressure treated to target copper retentions of 12.48 kg/m³ (0,78 pcf), 9.77 kg/m3 (0.61 pcf), 5.6 kg/m³ (0.35 pcf), 4.5 kg/m³ (0.30 pcf), 2.56 kg/m³ (0.16 pcf), 1.2 kg/m³ (0.075 pcf), 0.48 kg/m³ (0.03 pcf). Data from laboratory soil block tests indicate that at 2.0 ± 0.5 kg/m³ (0.13 pcf) copper retention from waterborne copper naphthenate, the protection is similar to that from a 1.6 kg/m³ (0.10 pcf) elementar copper from oilborne copper nathenate or 7.2 kg/m³ (0.45 pcf) total oxide from CCA-C. Higher copper levels (3.0 ± 0.2 kg/m³) are needed to protect against copper tolerant brown rot fungus Poria placenta. Results from an American Wood Preserver's Association standard leaching test on samples treated with waterborne copper naphthenate show that 10 to 20% of the copper initially absorbed is leached and the amount of copper leached increases with the pH of the leaching solution or with the copper loading in the samples.
D P Kamdem, R Fair, M H Freeman


Biological resistance of electrolessly plated wood (1). Preliminary report
1994 - IRG/WP 94-40024
Surface metal coating is considered to improve biological resistance of wood as some metal ions are fungitoxic. Six wood species (three softwoods: Cryptomeria japonica, Tsuga heterophylla and Larix spp; three hardwoods: Fagus crenata, Acer mono and Betula platyphylla) were electrolessly plated with nickel or copper, and those were served for laboratory evaluation of their resistance against decay fungi (Coriolus versicolor and Tyromyces palustris) and subterranean termites (Coptotermes formosanus). On the basis of weight losses after 12 weeks' decay test, all the plated wood species proved resistant against Coriolus versicolor, while none of the treatments could satisfactorily protect wood from decay by Tyromyces palustris. High termite resistance was produced in any case, and especially nickel-plated wood specimens caused 100% mortality of test termites within two weeks.
M Hasegawa, K Tsunoda, T Yoshimura


The micro-distribution of copper/chrome/arsenate in Acer pseudoplatanus and Eucalyptus maculata
1973 - IRG/WP 319
The excellent field performance of copper-chrome-arsenate (CCA) treated timber has been accepted for many years. The preservative loadings used in practice have been based on field trial results, backed by service tests. The performance of treated hardwoods in trials and practice indicated that provided the required loading and penetration could be achieved the performance would be good. Recent unexpected failures in a few hardwoods treated to specification indicate that some hardwoods behave differently in ground contact from the normal test species with equal preservative loadings. Field evidence with creosote suggests that some discrepancies can occur with other preservatives as well. The immediate problem is confined to a vary few species and in all cases failure has been due to soft-rot at the ground line. Petty & Preston (1968) demonstrated that CCA preservatives penetrate deeply into the tracheid wall of conifers affording excellent protection to the timber. It was decided to investigate the micro-distribution of CCA preservative components in two problem hardwood species, Acer pseudoplatanus and Eucalyptus maculata. If the components were found to be distributed less uniformly than in softwood tissues this could possibly account for the unexpected field performance of these hardwoods in ground contact.
D J Dickinson


Effects of pre-harvest girdling on selected properties of red pine, red maple and Eastern larch
1999 - IRG/WP 99-40137
Trees of three species - tamarack (Larix laricina), soft maple (Acer rubrum) and red pine (Pinus resinosa) - were girdled immediately below the crown,one to two years before felling. The wood from these trees was compared with wood taken from un-girdled control trees felled at the same. Sapwood and heartwood, from the controls, and from above and below the girdle of treated trees, were examined for parenchyma viability, moisture content and various extractive components. The susceptibility of the wood to sap-stain and mould fungi, non-microbial staining and decay fungi was compared, as well as the wood's CCA treating characteristics. Results indicate that girdling changes the physical and chemical state of the wood and influences its susceptibility to sap-stain and mould fungi.
A Taylor, P A Cooper


Decay Resistance of Maple (Acer Insigne) Wood Against White Rot
2010 - IRG/WP 10-10740
In this study, the decay resistance of maple (Acer insigne) in natural state and treated with ACC (Acid copper chromate) was investigated against the white rot fungus (Coriolus versicolor). ACC is a kind of water borne preservatives that was used in this study for treating specimens under vacuum and pressure (Bethell procedure) with 3 percent concentration. In conducting mentioned evaluation, kolleschale’s method according to DIN 52176 and B.S. 838: 1961 were used in completely randomized block design. Specimens were contaminated with cultured fungus for fourteen weeks in condition (22, 75% relative humidity). After this period, weight reduction, compressive strength (parallel to grain) and hardness of specimens were tested. Under test conditions weight reduction of control sample were much higher than treated ones. Compressive strength (parallel to grain) and hardness of treated samples were higher than control ones.
V Tazakor Rezaei