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• 1. [Article] Wood Pole Maintenance Manual: 2012 Edition

  Morrell, Jeffrey J. 2012. Wood Pole Maintenance Manual: 2012 Edition. Research Contribution 51, Forest Research Laboratory, Oregon State University, Corvallis. The specification, inspection, ...

  Citation × Citation Citation Abstract Copy Title: Wood Pole Maintenance Manual: 2012 Edition Author: Morrell, Jeffrey J. Morrell, Jeffrey J. 2012. Wood Pole Maintenance Manual: 2012 Edition. Research Contribution 51, Forest Research Laboratory, Oregon State University, Corvallis. The specification, inspection, and remedial treatment of utility poles are addressed. Included are discussions of enhancing specifications for improved performance, techniques for detecting decay and other defects, and chemical treatments available for arresting decay of poles in service. Title: Wood Pole Maintenance Manual: 2012 Edition Author: Morrell, Jeffrey J. Morrell, Jeffrey J. 2012. Wood Pole Maintenance Manual: 2012 Edition. Research Contribution 51, Forest Research Laboratory, Oregon State University, Corvallis. The specification, inspection, and remedial treatment of utility poles are addressed. Included are discussions of enhancing specifications for improved performance, techniques for detecting decay and other defects, and chemical treatments available for arresting decay of poles in service. Close

• 2. [Article] A Note on the Sensitivity of A Closed-Tube Bioassay To Volatile Methylisothiocyanate Residues In Fumigant-Treated Wood

  A closed-tube bioassay with Poria placenta was used to measure residual fungistatic vapors in wood fumigated with methylisothiocyanate (MIT). This bioassay showed an inverse linear relationship between ...

  Citation × Citation Citation Abstract Copy Title: A Note on the Sensitivity of A Closed-Tube Bioassay To Volatile Methylisothiocyanate Residues In Fumigant-Treated Wood Author: Morrell, Jeffrey J., Zahora, Andrew R. A closed-tube bioassay with Poria placenta was used to measure residual fungistatic vapors in wood fumigated with methylisothiocyanate (MIT). This bioassay showed an inverse linear relationship between fungal growth and the amount of MIT in the wood samples. For fumigated increment-core sections of unseasoned Douglas-fir heartwood (4.8 mm in diameter by 25 mm long), the sensitivity of the bioassay ranged from 2 to 10 ug MIT per section. Closed-tube-bioassay response was also determined for small slivers of seasoned ponderosa pine and Douglas-fir, and was influenced by the size of the samples. Title: A Note on the Sensitivity of A Closed-Tube Bioassay To Volatile Methylisothiocyanate Residues In Fumigant-Treated Wood Author: Morrell, Jeffrey J., Zahora, Andrew R. A closed-tube bioassay with Poria placenta was used to measure residual fungistatic vapors in wood fumigated with methylisothiocyanate (MIT). This bioassay showed an inverse linear relationship between fungal growth and the amount of MIT in the wood samples. For fumigated increment-core sections of unseasoned Douglas-fir heartwood (4.8 mm in diameter by 25 mm long), the sensitivity of the bioassay ranged from 2 to 10 ug MIT per section. Closed-tube-bioassay response was also determined for small slivers of seasoned ponderosa pine and Douglas-fir, and was influenced by the size of the samples. Close

• 3. [Article] Properties and decay resistance of preservative-treated Douglas-fir flakeboard

  The effect of pretreatment of Douglas-fir flakes with CCA-C, borate, and azaconazole on properties of flakeboard was studied. Flakes had higher retention levels of CCA-C and borate in their ends than in ...

  Citation × Citation Citation Abstract Copy Title: Properties and decay resistance of preservative-treated Douglas-fir flakeboard Author: Jeihooni, Asghar, Krahmer, Robert L., Morrell, Jeffrey J. The effect of pretreatment of Douglas-fir flakes with CCA-C, borate, and azaconazole on properties of flakeboard was studied. Flakes had higher retention levels of CCA-C and borate in their ends than in their centers. The distribution of chemicals was uniform in panels, which indicates that the chemicals did not migrate during hot-pressing. Treatment markedly enhanced resistance to brown rot (Postia placenta). Borate-treated panels had large thickness swelling and often delaminated when exposed to hot, wet conditions. In static bending and internal bond tests, strength reduction for borate- and CCAC-treated panels was evident. Azaconazole showed no deleterious effect on strength. Title: Properties and decay resistance of preservative-treated Douglas-fir flakeboard Author: Jeihooni, Asghar, Krahmer, Robert L., Morrell, Jeffrey J. The effect of pretreatment of Douglas-fir flakes with CCA-C, borate, and azaconazole on properties of flakeboard was studied. Flakes had higher retention levels of CCA-C and borate in their ends than in their centers. The distribution of chemicals was uniform in panels, which indicates that the chemicals did not migrate during hot-pressing. Treatment markedly enhanced resistance to brown rot (Postia placenta). Borate-treated panels had large thickness swelling and often delaminated when exposed to hot, wet conditions. In static bending and internal bond tests, strength reduction for borate- and CCAC-treated panels was evident. Azaconazole showed no deleterious effect on strength. Close

• 4. [Article] Controlling decay fungi in Douglas-fir heartwood with pelletized sodium n-methyldithiocarbamate

  A small block test was used in assessing whether pelletized sodium n-methyldithiocarbamate (NaMDC) would decompose and produce methylisothiocyanate (MITC) and thereby eliminate Antrodia carbonica colonies ...

  Citation × Citation Citation Abstract Copy Title: Controlling decay fungi in Douglas-fir heartwood with pelletized sodium n-methyldithiocarbamate Author: Sexton, Camille M., Morrell, Jeffrey J., Newbill, Mark A. A small block test was used in assessing whether pelletized sodium n-methyldithiocarbamate (NaMDC) would decompose and produce methylisothiocyanate (MITC) and thereby eliminate Antrodia carbonica colonies from Douglas-fir heartwood. Also evaluated were the effects of wood moisture content, dosage, incubation period, pH level, and presence of copper sulfate on percentage of kill of the fungus and amount of MITC in the wood. Increasing moisture content produced the most dramatic increases in MITC production and fungal control. The effects of pH and the presence of copper ions were more variable. The results indicate that pelletized NaMDC can effectively control fungal infestations in Douglas-fir heartwood. Field studies are planned. Title: Controlling decay fungi in Douglas-fir heartwood with pelletized sodium n-methyldithiocarbamate Author: Sexton, Camille M., Morrell, Jeffrey J., Newbill, Mark A. A small block test was used in assessing whether pelletized sodium n-methyldithiocarbamate (NaMDC) would decompose and produce methylisothiocyanate (MITC) and thereby eliminate Antrodia carbonica colonies from Douglas-fir heartwood. Also evaluated were the effects of wood moisture content, dosage, incubation period, pH level, and presence of copper sulfate on percentage of kill of the fungus and amount of MITC in the wood. Increasing moisture content produced the most dramatic increases in MITC production and fungal control. The effects of pH and the presence of copper ions were more variable. The results indicate that pelletized NaMDC can effectively control fungal infestations in Douglas-fir heartwood. Field studies are planned. Close

• 5. [Article] Internal pressure measurement techniques and pressure response in wood during treating processes

  The development of pressure inside wood during preservative impregnation was studied using Douglas-fir heartwood and ponderosa pine sapwood. Pressure sensors mounted on sample holders provided the most ...

  Citation × Citation Citation Abstract Copy Title: Internal pressure measurement techniques and pressure response in wood during treating processes Author: Levien, Keith L., Morrell, Jeffrey J., Schneider, Philip F. The development of pressure inside wood during preservative impregnation was studied using Douglas-fir heartwood and ponderosa pine sapwood. Pressure sensors mounted on sample holders provided the most reliable measurements. As expected, pressure equilibrated most rapidly with air as the treatment medium and ponderosa pine as the test species. Pressure changes were relatively slow in Douglas-fir heartwood, suggesting that process conditions involving relatively rapid changes in pressure conditions will have little effect on fluid penetration away from the wood surface. Title: Internal pressure measurement techniques and pressure response in wood during treating processes Author: Levien, Keith L., Morrell, Jeffrey J., Schneider, Philip F. The development of pressure inside wood during preservative impregnation was studied using Douglas-fir heartwood and ponderosa pine sapwood. Pressure sensors mounted on sample holders provided the most reliable measurements. As expected, pressure equilibrated most rapidly with air as the treatment medium and ponderosa pine as the test species. Pressure changes were relatively slow in Douglas-fir heartwood, suggesting that process conditions involving relatively rapid changes in pressure conditions will have little effect on fluid penetration away from the wood surface. Close

• 6. [Article] Supercritical carbon dioxide treatment: Effect on permeability of Douglas-fir heartwood

  The effect of supercritical fluid treatment on superficial gas permeability of Douglas-fir was investigated by using carbon dioxide either alone or amended with methanol. Permeability increased in a majority ...

  Citation × Citation Citation Abstract Copy Title: Supercritical carbon dioxide treatment: Effect on permeability of Douglas-fir heartwood Author: Hassan, Ali, Levien, Keith L., Morrell, Jeffrey J., Kumar, Satish, Demessie, Endalkachew Sahle The effect of supercritical fluid treatment on superficial gas permeability of Douglas-fir was investigated by using carbon dioxide either alone or amended with methanol. Permeability increased in a majority of samples, although nearly one-third of the specimens declined in permeability. Improvements in permeability appeared to be unrelated to variations in temperature, pressure, or the presence of a cosolvent, suggesting that the conditions were uniformly suitable for extractive solubilization. Decreased permeability may reflect redeposition of solubilized extractives to positions where they again diminish permeability as conditions drop out of the critical range, a possibility that will be studied further. Title: Supercritical carbon dioxide treatment: Effect on permeability of Douglas-fir heartwood Author: Hassan, Ali, Levien, Keith L., Morrell, Jeffrey J., Kumar, Satish, Demessie, Endalkachew Sahle The effect of supercritical fluid treatment on superficial gas permeability of Douglas-fir was investigated by using carbon dioxide either alone or amended with methanol. Permeability increased in a majority of samples, although nearly one-third of the specimens declined in permeability. Improvements in permeability appeared to be unrelated to variations in temperature, pressure, or the presence of a cosolvent, suggesting that the conditions were uniformly suitable for extractive solubilization. Decreased permeability may reflect redeposition of solubilized extractives to positions where they again diminish permeability as conditions drop out of the critical range, a possibility that will be studied further. Close

• 7. [Article] Decay resistance of saltwater-exposed Douglas-fir piles

  Wood that is submerged in fresh water for long periods has increased permeability and other changed properties. Wood that is submerged in salt water may absorb considerable quantities of salts, which may ...

  Citation × Citation Citation Abstract Copy Title: Decay resistance of saltwater-exposed Douglas-fir piles Author: Freitag, Camille M., Morrell, Jeffrey J., Schneider, Philip F. Wood that is submerged in fresh water for long periods has increased permeability and other changed properties. Wood that is submerged in salt water may absorb considerable quantities of salts, which may render the wood resistant to microbial colonization. In this report, we describe decay tests on Douglas-fir sapwood and heartwood after long-term exposure in the Great Salt Lake of Utah. This wood was generally resistant to fungal attack, but was susceptible to leaching. Scanning electron microscopic examination revealed that salt crystals in the wood were primarily sodium chloride, which was readily removed in a leaching procedure. Decay resistance attributed to saltwater exposure declined with prolonged leaching. Title: Decay resistance of saltwater-exposed Douglas-fir piles Author: Freitag, Camille M., Morrell, Jeffrey J., Schneider, Philip F. Wood that is submerged in fresh water for long periods has increased permeability and other changed properties. Wood that is submerged in salt water may absorb considerable quantities of salts, which may render the wood resistant to microbial colonization. In this report, we describe decay tests on Douglas-fir sapwood and heartwood after long-term exposure in the Great Salt Lake of Utah. This wood was generally resistant to fungal attack, but was susceptible to leaching. Scanning electron microscopic examination revealed that salt crystals in the wood were primarily sodium chloride, which was readily removed in a leaching procedure. Decay resistance attributed to saltwater exposure declined with prolonged leaching. Close

• 8. [Article] The effect of pH on decomposition of Mylone (dazomet) and tridipam to fungitoxic methylisothiocyanate in wood

  Mylone@ and tridipam are two solid chemicals that decompose to produce methylisothiocyanate (MIT), a highly effective wood fumigant. In this study, two techniques -- a rapid, test-tube method and small-scale, ...

  Citation × Citation Citation Abstract Copy Title: The effect of pH on decomposition of Mylone (dazomet) and tridipam to fungitoxic methylisothiocyanate in wood Author: Lebow, Stan, Morrell, Jeffrey J., Sexton, Camille M. Mylone@ and tridipam are two solid chemicals that decompose to produce methylisothiocyanate (MIT), a highly effective wood fumigant. In this study, two techniques -- a rapid, test-tube method and small-scale, wood-block assay -- were used to determine the effect of the pH of various chemical buffers on the decomposition of Mylone@ and tridipam in Douglas-fir heartwood samples colonized by Poria carbonica. Both chemicals were sensitive to pH, and higher levels of MIT were produced as the pH of the buffers increased. In general, fungal survival was not affected 1 week after chemical treatment. Complete control of P. carbonica, however, resulted after 4 weeks of exposure to 50 mg Mylone@/block or 150 mg tridipam/block, when each chemical was combined with a pH-12 buffer. These results suggest that regulating fumigant treatments according to the degree of fungal attack can substantially improve the precision of decay control in wood maintenance programs. Title: The effect of pH on decomposition of Mylone (dazomet) and tridipam to fungitoxic methylisothiocyanate in wood Author: Lebow, Stan, Morrell, Jeffrey J., Sexton, Camille M. Mylone@ and tridipam are two solid chemicals that decompose to produce methylisothiocyanate (MIT), a highly effective wood fumigant. In this study, two techniques -- a rapid, test-tube method and small-scale, wood-block assay -- were used to determine the effect of the pH of various chemical buffers on the decomposition of Mylone@ and tridipam in Douglas-fir heartwood samples colonized by Poria carbonica. Both chemicals were sensitive to pH, and higher levels of MIT were produced as the pH of the buffers increased. In general, fungal survival was not affected 1 week after chemical treatment. Complete control of P. carbonica, however, resulted after 4 weeks of exposure to 50 mg Mylone@/block or 150 mg tridipam/block, when each chemical was combined with a pH-12 buffer. These results suggest that regulating fumigant treatments according to the degree of fungal attack can substantially improve the precision of decay control in wood maintenance programs. Close

• 9. [Article] Interactions of ammoniacal copper zinc arsenate (ACZA) with Douglas-fir

  Tests were conducted to determine the effect of ACZA composition on fixation and the roles of adsorption and precipitation in fixation. The sites of copper and zinc adsorption within the treated wood and ...

  Citation × Citation Citation Abstract Copy Title: Interactions of ammoniacal copper zinc arsenate (ACZA) with Douglas-fir Author: Lebow, Stan T., Morrell, Jeffrey J. Tests were conducted to determine the effect of ACZA composition on fixation and the roles of adsorption and precipitation in fixation. The sites of copper and zinc adsorption within the treated wood and the bonding environment of adsorbed copper were also examined. The results generally support the finding that arsenic fixation occurs by precipitation of metal/arsenate complexes. Arsenic leaching was minimized with high solution ratios of metal oxide:arsenic pentoxide, and with formulations containing zinc. Zinc precipitated the majority of arsenic when ammonia was allowed to evaporate from the treating solution. The metal cations were leach-resistant regardless of ACZA formulation because of their low water solubility and their ability to adsorb to the wood. Copper was readily adsorbed by lignin and by model compounds that possessed phenolic hydroxyl groups, which suggests that phenolic hydroxyl groups were the primary reaction sites. Fourier Transform Infrared (FTIR) and Fast Atom Bombardment (FAB) mass spectroscopy analysis also supported this conclusion. Multiple copper species and increased free radical content were detected within lignin that had adsorbed copper. Adsorption of copper and zinc has important ramifications for arsenic fixation. Title: Interactions of ammoniacal copper zinc arsenate (ACZA) with Douglas-fir Author: Lebow, Stan T., Morrell, Jeffrey J. Tests were conducted to determine the effect of ACZA composition on fixation and the roles of adsorption and precipitation in fixation. The sites of copper and zinc adsorption within the treated wood and the bonding environment of adsorbed copper were also examined. The results generally support the finding that arsenic fixation occurs by precipitation of metal/arsenate complexes. Arsenic leaching was minimized with high solution ratios of metal oxide:arsenic pentoxide, and with formulations containing zinc. Zinc precipitated the majority of arsenic when ammonia was allowed to evaporate from the treating solution. The metal cations were leach-resistant regardless of ACZA formulation because of their low water solubility and their ability to adsorb to the wood. Copper was readily adsorbed by lignin and by model compounds that possessed phenolic hydroxyl groups, which suggests that phenolic hydroxyl groups were the primary reaction sites. Fourier Transform Infrared (FTIR) and Fast Atom Bombardment (FAB) mass spectroscopy analysis also supported this conclusion. Multiple copper species and increased free radical content were detected within lignin that had adsorbed copper. Adsorption of copper and zinc has important ramifications for arsenic fixation. Close

• 10. [Article] Steady-state diffusion of chloropicrin in Douglas-fir heartwood

  The effects of moisture content, flow direction, concentration, and temperature on the diffusion of chloropicrin in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) heartwood were investigated. Diffusion ...

  Citation × Citation Citation Abstract Copy Title: Steady-state diffusion of chloropicrin in Douglas-fir heartwood Author: Peralta, Perry N., Morrell, Jeffrey J. The effects of moisture content, flow direction, concentration, and temperature on the diffusion of chloropicrin in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) heartwood were investigated. Diffusion coefficients were strongly affected by wood moisture content. Coefficients for radial and tangential diffusion at the fiber-saturation point were twice as high as those at the oven-dry condition. Longitudinal diffusion coefficients, however, increased only 12.5% when the moisture content was increased over the same range. Longitudinal diffusion coefficients were about three orders of magnitude higher than those in the transverse directions, while there was no significant difference between radial and tangential diffusion coefficients. Diffusion coefficients were independent of concentration, showing the validity of Fick's law of diffusion in characterizing the flow of the fumigant in wood. Diffusion coefficients were always higher at 35 C than at 20 C; however, the difference was not statistically significant, suggesting that the flow of the fumigant is not a temperature-activated process. Title: Steady-state diffusion of chloropicrin in Douglas-fir heartwood Author: Peralta, Perry N., Morrell, Jeffrey J. The effects of moisture content, flow direction, concentration, and temperature on the diffusion of chloropicrin in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) heartwood were investigated. Diffusion coefficients were strongly affected by wood moisture content. Coefficients for radial and tangential diffusion at the fiber-saturation point were twice as high as those at the oven-dry condition. Longitudinal diffusion coefficients, however, increased only 12.5% when the moisture content was increased over the same range. Longitudinal diffusion coefficients were about three orders of magnitude higher than those in the transverse directions, while there was no significant difference between radial and tangential diffusion coefficients. Diffusion coefficients were independent of concentration, showing the validity of Fick's law of diffusion in characterizing the flow of the fumigant in wood. Diffusion coefficients were always higher at 35 C than at 20 C; however, the difference was not statistically significant, suggesting that the flow of the fumigant is not a temperature-activated process. Close