Your search resulted in 142 documents. Displaying 25 entries per page.
Accelerated laboratory testing of preservatives on 13 North American wood species
1999 - IRG/WP 99-30201
The ability of selected water and solvent based biocides to protect wood against fungal attack was evaluated on 13 North American wood species using 7 decay fungi in a modified soil block test. Most preservatives were capable of providing protection at their recommended above ground and soil contact use levels. Many decay fungi caused substantial weight losses on blocks treated with chlorothalonil...
J J Morrell, C M Freitag
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 effici...
J J Morrell
Feasibility of using biological control agents to arrest and prevent colonization of Douglas fir and southern pine by decay fungi
1988 - IRG/WP 1345
The use of microfungi to control basidiomycetous decay has been evaluated in Europe for many years, where it has produced mixed results against Lentinus lepideus Fries, the fungus presumed to be the major cause of decay in Scots Pine poles. In the United States, remedial decay control has been largely chemical, with little use of alternative decay control strategies. Increasing restrictions on che...
J J Morrell, C M Sexton
The effect of glycol additives on diffusion of boron through Douglas-fir
2000 - IRG/WP 00-30235
Boron is highly effective against a variety of fungi and insects and is able to diffuse with moisture through wood. Diffusion decreases sharply at lower moisture contents, a characteristic that limits the potential use of this material as a remedial treatment for arresting internal decay. One approach to improvi ng boron diffusion is the simultaneous addition of glycol, which is presumed to enhanc...
C M Freitag, R Rhatigan, J J Morrell
Effect of kerfing on performance of Douglas-fir utility poles in the Pacific Northwest
1990 - IRG/WP 3604
Preservative treatment produces an external layer of protection in Douglas-fir poles, but the development of deep checks as the wood dries after treatment can permit entry by fungi and insects. A variety of remedial treatments can arrest this decay; however, it is far more efficient to prevent checking. Kerfing represents one potential method for limiting the development of deep checks. In previou...
J J Morrell
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 microscopi...
M E Anderson, R J Leichti, J J Morrell
A review of incising as a means of improving treatment of sawnwood
1994 - IRG/WP 94-40019
The use of incising, perforation of the wood surface, is increased because of the need to treat refractory wood species. This paper reviews the development of incising and shows how the required incising patterns can be determined and specified. Most of the development has been in the area of toothed-roller incisors because of their rapid throughput. Needle, Laser, drill and water jet incisors hav...
P I Morris, J J Morrell, J N R Ruddick
Ability of chloropicrin, Vorlex, or methylisothiocyante to prevent marine borer attack of Douglas fir piling
1989 - IRG/WP 4153
The preservative-treated shell around Douglas-fir piling is an excellent barrier to attack by marine borers; however, damage to this shell can permit marine borer attack. The feasibility of using fumigants to enhance piling performance was examined by exposing fumigant-treated Douglas-fir sections in marine waters off Newport, OR, or Port Hueneme, CA. The piling were inspected annually and increme...
M A Newbill, J J Morrell
Integrated protection of freshly sawn lumber using Bacillus subtilis and selected fungicide
1997 - IRG/WP 97-10235
Bioprotection against stain fungi has tremendous potential for reducing discoloration of freshly sawn wood while decreasing chemical consumption. Unfortunately, most bioprotectants appear to be unable to consistently perform under the array of conditions to which freshly sawn wood is exposed. While research is underway to understand the nature of the inconsistent performance, a more pragmatic appr...
M E Mankowski, M Anderson, J J Morrell
Supercritical fluid impregnation of Douglas-fir heartwood with cyproconazole using temperature induced deposition
2003 - IRG/WP 03-40259
A limited understanding of the fundamental aspects of supercritical fluid (SCF) impregnation in wood remains an obstacle to the development of this technology. Developing a better understanding of the effects of various process parameters on treatment results would facilitate more rational development of SCF impregnation. In this project, the effect of treating period and specimen length on su...
Sung-Mo Kang, J J Morrell
Supercritical fluid treatment: Effects on bending strength of white spruce heartwood
1993 - IRG/WP 93-20008
The effects of supercritical carbon dioxide on wood strength were evaluated using white spruce heartwood, a species known to be especially susceptible to collapse during exposure to higher pressures. The effects of pressures of 2000 or 3600 psig and temperatures of 40 or 80°C were evaluated using 30 or 60 minute exposure periods. No significant differences were noted in modulus of rupture or modu...
S M Smith, J J Morrell, E Sahle-Demessie, K L Levien
Performance of Paraserianthus falcataria treated with ACZA, ACQ, CC or CCA and exposed in Krishnapatnam harbour, India
2005 - IRG/WP 05-30382
Paraserianthus falcataria (=Albizia falcataria) treated to two retentions with ammoniacal copper zinc arsenate (ACZA), ammoniacal copper quaternary (ACQ), ammoniacal copper citrate (CC) and chromated copper arsenate (CCA) was assessed over 34 months in a tropical marine waters at Krishnapatnam harbour on the east coast of India. ACZA treatment showed comparatively better resistance than CCA, ACQ a...
B Tarakanadha, K S Rao, J J Morrell
Ability of an acoustic inspection device to detect internal voids
in untreated pole sections
2002 - IRG/WP 02-20246
Detecting deterioration before substantial losses in material properties occur poses a major challenge to most wood users. While physical inspection techniques such as drilling or coring are useful, these methods can miss small pockets of damage and they lack the ability to detect early or incipient decay. The development of sonic test methodologies has created the potential for detecting change...
J J Morrell, R G Rhatigan
Relative merits of laboratory and field tests for assessing wood decay resistance
1993 - IRG/WP 93-20009
Laboratory and field trials have long been employed for assessing natural durability of a variety of wood species, but there is a continuing debate concerning the relative merits of approach. While laboratory tests provide carefully controlled conditions for decay, they are often criticized for being too artificial to produce meaningful results. Conversely, field trials often vary widely between t...
T C Scheffer, J J Morrell
Effect of nutrient regimes, temperature, pH, and wood sterilization method on performance of selected bioprotectants against wood staining fungi
1992 - IRG/WP 92-1551
The effect of nutrient regimes, incubation temperature, media pH, and wood sterilization method on performance of four potential bioprotectants (Pseudomonas putida, Pseudomonas cepacia, Bacillus subtilis, and Trichoderma harzianum) against wood staining fungi were evaluated using small ponderosa pine samples over a four week period. Incubation at 32°C resulted in slight increases in the degree of...
J J Morrell, C M Secton
Preliminary evaluations of a small wafer assay for screening potential biological control agents
1989 - IRG/WP 2332
Screening potential biological agents for controlling wood decay fungi poses a dilemma. The ideal test would eliminate as many variables as possible. Most tests utilize pure cultures of the test organism on an artificial media which in no way resembles wood. The use of sawdust improves this approach, but the sawdust increases fungal access to the lignocellulose matrix, potentially inflating the im...
C M Freitag, J J Morrell
A comparison between high and conventional incision densities for improving preservative treatment of Douglas-fir heartwood lumber
1993 - IRG/WP 93-40009
Incising is required for the preservative treatment of most wood species from the western United States; however, there is considerable debate about the density of incisions required to achieve adequate treatment. Previous studies have shown that the incision effect on treatment is relatively narrow, suggesting that incision densities should be significantly increased over current practices and st...
S T Lebow, J J Morrell
Effects of Prior Establishment of Trichoderma harzianum on Ophiostoma picea Growth in Freshly Sawn Douglas-fir Sapwood
2003 - IRG/WP 03-10476
Trichoderma harzianum has been shown to be an effective biocontrol agent against a number of wood inhabiting fungi under laboratory conditions, but this fungus has performed poorly in field trials. Understanding the interactions between biocontrol agents and their intended targets in wood may provide important clues for developing improved approaches to biocontrol, potentially reducing our relianc...
Ying Xiao, J J Morrell, L M Ciuffetti
Potential for using dip/supercritical fluid treatments for wood impregnation
2004 - IRG/WP 04-40276
While supercritical fluid impregnation offers tremendous potential for impregnating wood species that resist conventional liquid preservative treatments, the resulting treatments are often not uniform among samples in a charge or between charges. One factor that influences treatment is the dynamic change in pressure that occurs during introduction of the biocide laden supercritical fluid into the ...
Sung-Mo Kang, J J Morrell
Fluoride movement through Douglas-fir and hem-fir lumber following dipping in potassium/ammonium bifluoride
1995 - IRG/WP 95-40040
The ability of ammonium and potassium fluoride to diffuse through Douglas-fir and hem-fir lumber was evaluated over a 90 day period. Boards were dipped in a solution containing 10% (by weight) of ammonium and potassium bifluoride, then stored under cover for 90 days. Samples removed 30, 60 and 90 days after treatment indicated that the fluoride was unable to completely penetrate the wood. Penetrat...
J J Morrell, C S Love
Biological control of wood decay fungi. - Part II. Effects of exogenous nitrogen on effectiveness
2000 - IRG/WP 00-10360
The effects of nitrogen (urea and ammonium nitrate) on the ability of Trichoderma harzianum to inhibit the enzyme capabilities and decay capacities of Trametes versicolor and Gloeophyllum trabeum were investigated using a small wood sandwich decay test. The biocontrol fungus generally had a greater effect on the brown rot fungus, confirming previous reports. Nitrogen produced inconsistent effects ...
E A Canessa, J J Morrell
Sterilization to limit pretreatment decay: Internal temperature during kiln drying of Douglas-fir poles
2001 - IRG/WP 01-40206
Sterilization to limit pretreatment decay: Internal temperature during kiln drying of Douglas-fir poles. Fungal colonization of poles following peeling has been the subject of considerable concern among electric utilities. While the presence of fungi does not, in itself constitute a risk, the survival of these fungi through the conventional treating processes could allow them to continue to degrad...
J J Morrell, P G Forsyth, K L Levien
Effects of air-seasoning on fungal colonization and wood strength of Douglas fir poles
1987 - IRG/WP 1315
Air seasoning economically reduces the moisture content of Douglas fir poles before pressure treatment with preservatives. Advanced decay in poles in service has resulted when decay fungi (Basidiomycetes) colonized poles during air-seasoning and survived the treatment process. These problems have led to recommendations to severely limit this practice. To determine the role of these fungi in peeled...
J J Morrell, M E Corden, R D Graham, B L Kropp, P Przybylowicz, S M Smith, C A Sexton
Effect of substrate type and moisture requirements in relation to colony initiation in two carpenter ant species
1999 - IRG/WP 99-10320
Conditions necessary for optimal colony initiation or the rate of initial colony expansion by early brood in the carpenter ant species Camponotus modoc and C. vicinus on various substrates conditioned to different moisture contents were studied. Camponotus modoc and Camponotus vicinus queens were placed in Douglas-fir, western red cedar and Styrofoam® blocks conditioned in sealed chambers at 70% ...
M E Mankowski, J J Morrell
Marine performance of preservative treated Southern pine panels. - Part 1: Exposure in Newport, Oregon
2000 - IRG/WP 00-10368
The ability of selected wood preservative to protect southern pine sapwood against marine borer attack was evaluated over a 6 year period in Yaquina Bay, Oregon. The site exposed the wood to potential attack by both Teredo navalis and Limnoria spp. Both creosote and CCA provided excellent protection at moderate retentions, while ACQ produced slight differences in performance depending on the coppe...
R G Rhatigan, J J Morrell, A R Zahora