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• 31. [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

• 32. [Article] Copper, chromium, and arsenic levels in soils surrounding posts treated with chromated copper arsenate (CCA)

  The levels of copper, chromium, and arsenic in soil surrounding CCA-treated posts and beneath CCA-treated stakes were investigated at a plot near Gainesville, Florida. Metal levels were elevated in soil ...

  Citation × Citation Citation Abstract Copy Title: Copper, chromium, and arsenic levels in soils surrounding posts treated with chromated copper arsenate (CCA) Author: Morrell, Jeffrey J., Huffman, Jacob The levels of copper, chromium, and arsenic in soil surrounding CCA-treated posts and beneath CCA-treated stakes were investigated at a plot near Gainesville, Florida. Metal levels were elevated in soil immediately adjacent to the treated wood, but decreased with distance away or depth. Mean extractable arsenic levels ranged from 1.74 to 8.19 ppm immediately adjacent to the posts, but declined to less than 1 ppm in samples 150 and 300 mm away, regardless of depth sampled. The results suggest that soil contamination due to the presence of CCA-treated wood for 45 years is minimal. Title: Copper, chromium, and arsenic levels in soils surrounding posts treated with chromated copper arsenate (CCA) Author: Morrell, Jeffrey J., Huffman, Jacob The levels of copper, chromium, and arsenic in soil surrounding CCA-treated posts and beneath CCA-treated stakes were investigated at a plot near Gainesville, Florida. Metal levels were elevated in soil immediately adjacent to the treated wood, but decreased with distance away or depth. Mean extractable arsenic levels ranged from 1.74 to 8.19 ppm immediately adjacent to the posts, but declined to less than 1 ppm in samples 150 and 300 mm away, regardless of depth sampled. The results suggest that soil contamination due to the presence of CCA-treated wood for 45 years is minimal. Close

• 33. [Article] Durability of a changing western redcedar resource

  The heartwood of western redcedar (Thuja plicuta) is known for its natural resistance to fungal attack, but some users of western redcedar utility poles have suggested that its durability may be diminished ...

  Citation × Citation Citation Abstract Copy Title: Durability of a changing western redcedar resource Author: Freitag, Camille M., Morrell, Jeffrey J. The heartwood of western redcedar (Thuja plicuta) is known for its natural resistance to fungal attack, but some users of western redcedar utility poles have suggested that its durability may be diminished as suppliers begin to harvest trees from younger stands. The decay resistance of western redcedar samples from the Pacific Northwest and Idaho was tested by using Postia placenta in a soil block test. Weight losses varied widely among and between sites and were not correlated with position in the heartwood cross section, tree age, or silvicultural factors. With results similar to those from a 1957 study, we can infer that the durability of the currently used younger material has not changed from that of earlier, older stocks. Title: Durability of a changing western redcedar resource Author: Freitag, Camille M., Morrell, Jeffrey J. The heartwood of western redcedar (Thuja plicuta) is known for its natural resistance to fungal attack, but some users of western redcedar utility poles have suggested that its durability may be diminished as suppliers begin to harvest trees from younger stands. The decay resistance of western redcedar samples from the Pacific Northwest and Idaho was tested by using Postia placenta in a soil block test. Weight losses varied widely among and between sites and were not correlated with position in the heartwood cross section, tree age, or silvicultural factors. With results similar to those from a 1957 study, we can infer that the durability of the currently used younger material has not changed from that of earlier, older stocks. Close

• 34. [Article] Methylisothiocyanate fumigant content of Douglas-fir heartwood at various moisture levels after treatment with solid sodium N-methyldithiocarbamate

  The relationship between moisture content and the presence of methylisothiocyanate (MITC) in wood following various applications of sodium n-methyldithiocarbamate (NaMDC) was investigated with small Douglas-fir ...

  Citation × Citation Citation Abstract Copy Title: Methylisothiocyanate fumigant content of Douglas-fir heartwood at various moisture levels after treatment with solid sodium N-methyldithiocarbamate Author: Lebow, Stan T., Morrell, Jeffrey J. The relationship between moisture content and the presence of methylisothiocyanate (MITC) in wood following various applications of sodium n-methyldithiocarbamate (NaMDC) was investigated with small Douglas-fir heartwood blocks. While MITC levels were initially higher in wetter blocks, MITC levels in drier blocks remained more stable over the 8-week test period. The addition of water as well as NaMDC to blocks enhanced MITC levels only initially; this effect declined over the test period for blocks at 30% MC or greater. In comparing the effect on MITC levels of applying the NaMDC in powder or pellet form, no significant difference between the two application methods emerged. Title: Methylisothiocyanate fumigant content of Douglas-fir heartwood at various moisture levels after treatment with solid sodium N-methyldithiocarbamate Author: Lebow, Stan T., Morrell, Jeffrey J. The relationship between moisture content and the presence of methylisothiocyanate (MITC) in wood following various applications of sodium n-methyldithiocarbamate (NaMDC) was investigated with small Douglas-fir heartwood blocks. While MITC levels were initially higher in wetter blocks, MITC levels in drier blocks remained more stable over the 8-week test period. The addition of water as well as NaMDC to blocks enhanced MITC levels only initially; this effect declined over the test period for blocks at 30% MC or greater. In comparing the effect on MITC levels of applying the NaMDC in powder or pellet form, no significant difference between the two application methods emerged. Close

• 35. [Article] In-situ measurement of dimensional changes during supercritical fluid impregnation of white spruce lumber

  Supercritical fluids can markedly enhance preservative treatment of wood, but the high pressures employed can lead to collapse. We investigated the effects of the rates of pressure application and release ...

  Citation × Citation Citation Abstract Copy Title: In-situ measurement of dimensional changes during supercritical fluid impregnation of white spruce lumber Author: Morrell, Jeffrey J., Kim, Gyu Hyeok Supercritical fluids can markedly enhance preservative treatment of wood, but the high pressures employed can lead to collapse. We investigated the effects of the rates of pressure application and release on displacement of white spruce lumber during supercritical impregnation with carbon dioxide. Displacement was greatest when pressure was rapidly increased at the start of the process. Conversely, rapid pressure release at the conclusion of the treatment process resulted in the lowest level of permanent displacement. The results suggest that wood displacement during supercritical fluid impregnation can be controlled by altering process variables for a given species. Title: In-situ measurement of dimensional changes during supercritical fluid impregnation of white spruce lumber Author: Morrell, Jeffrey J., Kim, Gyu Hyeok Supercritical fluids can markedly enhance preservative treatment of wood, but the high pressures employed can lead to collapse. We investigated the effects of the rates of pressure application and release on displacement of white spruce lumber during supercritical impregnation with carbon dioxide. Displacement was greatest when pressure was rapidly increased at the start of the process. Conversely, rapid pressure release at the conclusion of the treatment process resulted in the lowest level of permanent displacement. The results suggest that wood displacement during supercritical fluid impregnation can be controlled by altering process variables for a given species. Close

• 36. [Article] Controlling hardwood sapstain : trials of stain-preventive products on red alder lumber

  Production of hardwood lumber (mostly red alder) has been a small but growing part of the forest products industry in the Pacific Northwest. In laboratory tests, Rodewod® 200 EC plus borax protected alder ...

  Citation × Citation Citation Abstract Copy Title: Controlling hardwood sapstain : trials of stain-preventive products on red alder lumber Author: Morrell, Jeffrey J., Oregon State University. Forest Research Laboratory, Miller, Donald J. (Donald James) Production of hardwood lumber (mostly red alder) has been a small but growing part of the forest products industry in the Pacific Northwest. In laboratory tests, Rodewod® 200 EC plus borax protected alder at nearly all levels tested. Eight other chemicals provided some protection at the highest level tested. Fungal-stain preventive treatments were evaluated on red alder lumber in both an accelerated 6-week test on small specimens In the laboratory and on bundled boards (1 inch x 4 inches x 8 feet) exposed outdoors for 2 or 6 months. Strong solutions of RODEWOD® 300. PQ-8 plus borax, and Permatox 101 protected freshly sawed red alder lumber that was solid-piled and stored for 2 months during which summer temperatures peaked. None of the treatments provided good protection through 6 months of storage that included summer weather. Title: Controlling hardwood sapstain : trials of stain-preventive products on red alder lumber Author: Morrell, Jeffrey J., Oregon State University. Forest Research Laboratory, Miller, Donald J. (Donald James) Production of hardwood lumber (mostly red alder) has been a small but growing part of the forest products industry in the Pacific Northwest. In laboratory tests, Rodewod® 200 EC plus borax protected alder at nearly all levels tested. Eight other chemicals provided some protection at the highest level tested. Fungal-stain preventive treatments were evaluated on red alder lumber in both an accelerated 6-week test on small specimens In the laboratory and on bundled boards (1 inch x 4 inches x 8 feet) exposed outdoors for 2 or 6 months. Strong solutions of RODEWOD® 300. PQ-8 plus borax, and Permatox 101 protected freshly sawed red alder lumber that was solid-piled and stored for 2 months during which summer temperatures peaked. None of the treatments provided good protection through 6 months of storage that included summer weather. Close

• 37. [Article] Effects of Postlayup Borate Treatment on Appearance and Flexural Properties of Douglas-Fir Glued Laminated Beams

  Preservative treatments are required whenever glued laminated beams are exposed outdoors. Treatments can be either water-based systems applied to individual laminations prior to layup or organic solvent–borne ...

  Citation × Citation Citation Abstract Copy Title: Effects of Postlayup Borate Treatment on Appearance and Flexural Properties of Douglas-Fir Glued Laminated Beams Author: Morrell, Jeffrey J., Long, Brady Preservative treatments are required whenever glued laminated beams are exposed outdoors. Treatments can be either water-based systems applied to individual laminations prior to layup or organic solvent–borne systems applied after the beams are fabricated. Water-based systems are not recommended for posttreatment because of concerns over checking and the potential for reductions in flexural properties, but there are few data on the effects of these treatments. The effects of pressure treatment with disodium octaborate tetrahydrate (boron) on flexural properties, glue-line shear, and visual appearance were investigated using Douglas-fir (Pseudotsuga menziesii) glued laminated beams. While treatment did result in the presence of drying checks on some beams, boron treatment followed by air seasoning or mild kiln drying did not produce any significant effects on modulus of rupture, modulus of elasticity, or glue-line shear. The results indicate that boron treatment does not affect load-bearing properties. Title: Effects of Postlayup Borate Treatment on Appearance and Flexural Properties of Douglas-Fir Glued Laminated Beams Author: Morrell, Jeffrey J., Long, Brady Preservative treatments are required whenever glued laminated beams are exposed outdoors. Treatments can be either water-based systems applied to individual laminations prior to layup or organic solvent–borne systems applied after the beams are fabricated. Water-based systems are not recommended for posttreatment because of concerns over checking and the potential for reductions in flexural properties, but there are few data on the effects of these treatments. The effects of pressure treatment with disodium octaborate tetrahydrate (boron) on flexural properties, glue-line shear, and visual appearance were investigated using Douglas-fir (Pseudotsuga menziesii) glued laminated beams. While treatment did result in the presence of drying checks on some beams, boron treatment followed by air seasoning or mild kiln drying did not produce any significant effects on modulus of rupture, modulus of elasticity, or glue-line shear. The results indicate that boron treatment does not affect load-bearing properties. Close

• 38. [Article] Antifungal effects of hinokitiol and its sodium salt for wood protection

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by North Carolina State University, Department of Wood and Paper Science. The published article can ...

  Citation × Citation Citation Abstract Copy Title: Antifungal effects of hinokitiol and its sodium salt for wood protection Author: Freitag, Camille M., Morrell, Jeffrey J., Okabe, Toshihiro, Li, Shujun This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by North Carolina State University, Department of Wood and Paper Science. The published article can be found at: http://www.ncsu.edu/bioresources/. Title: Antifungal effects of hinokitiol and its sodium salt for wood protection Author: Freitag, Camille M., Morrell, Jeffrey J., Okabe, Toshihiro, Li, Shujun This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by North Carolina State University, Department of Wood and Paper Science. The published article can be found at: http://www.ncsu.edu/bioresources/. Close

• 39. [Article] Supercritical fluid (SCF) treatment: Its effect on bending strength and stiffness of ponderosa pine sapwood

  Adverse effects on mechanical properties from using a supercritical fluid (SCF) to increase preservative penetration of refractory woods were evaluated by treating small ponderosa pine sapwood specimens ...

  Citation × Citation Citation Abstract Copy Title: Supercritical fluid (SCF) treatment: Its effect on bending strength and stiffness of ponderosa pine sapwood Author: Levien, Keith L., Morrell, Jeffrey J., Smith, Susan M., Ng, Harry, Demessie, E. Sahle Adverse effects on mechanical properties from using a supercritical fluid (SCF) to increase preservative penetration of refractory woods were evaluated by treating small ponderosa pine sapwood specimens with supercritical carbon dioxide at 64 combinations of temperatures (35 to 80 C), pressure (1,000 to 4,000 psig), and time (0.5 to 2 h). Thereafter, the treated and identical untreated specimens were equilibrated to constant moisture content and tested for bending strength and stiffness. The SCF-treated and untreated specimens were not significantly different in modulus of rupture (MOR) or modulus of elasticity (MOE). Temperature, pressure, and time had no significant effect on MOR; there were interacting effects of these variables on MOE, although these interactions had no meaningful patterns. Title: Supercritical fluid (SCF) treatment: Its effect on bending strength and stiffness of ponderosa pine sapwood Author: Levien, Keith L., Morrell, Jeffrey J., Smith, Susan M., Ng, Harry, Demessie, E. Sahle Adverse effects on mechanical properties from using a supercritical fluid (SCF) to increase preservative penetration of refractory woods were evaluated by treating small ponderosa pine sapwood specimens with supercritical carbon dioxide at 64 combinations of temperatures (35 to 80 C), pressure (1,000 to 4,000 psig), and time (0.5 to 2 h). Thereafter, the treated and identical untreated specimens were equilibrated to constant moisture content and tested for bending strength and stiffness. The SCF-treated and untreated specimens were not significantly different in modulus of rupture (MOR) or modulus of elasticity (MOE). Temperature, pressure, and time had no significant effect on MOR; there were interacting effects of these variables on MOE, although these interactions had no meaningful patterns. Close

• 40. [Article] Effect of incising and preservative treatment on shear strength of nominal 2-inch lumber

  This study evaluated the effects of pretreatment incising of dry lumber and preservative treatment on the shear strength of 1980 pieces of 2 X 4 dimension lumber (nominal 50 mm X 100 mm X 3.6 m long). ...

  Citation × Citation Citation Abstract Copy Title: Effect of incising and preservative treatment on shear strength of nominal 2-inch lumber Author: Morrell, Jeffrey J., Gupta, Rakesh, Winandy, Jerrold E., Riyanto, Djoko S. This study evaluated the effects of pretreatment incising of dry lumber and preservative treatment on the shear strength of 1980 pieces of 2 X 4 dimension lumber (nominal 50 mm X 100 mm X 3.6 m long). Three species groups (Douglas-fir, Hem-Fir. and Spruce-Pine-Fir-South) and two commercially produced machine-stress-rated grades per species group were tested in torsion to determine their shear strength. Incising and preservative treatment produced significant reductions in the average shear strength of Douglas-fir, Hem-Fir, and Spruce-Pine-Fir-South dimension lumber. These effects need to be addressed through the development of more appropriate design values for uses of preservative-treated wood of these species when shear is a governing factor. An adjustment factor of 0.70 is proposed for incised and preservative-treated nominal 2-inch lumber. Title: Effect of incising and preservative treatment on shear strength of nominal 2-inch lumber Author: Morrell, Jeffrey J., Gupta, Rakesh, Winandy, Jerrold E., Riyanto, Djoko S. This study evaluated the effects of pretreatment incising of dry lumber and preservative treatment on the shear strength of 1980 pieces of 2 X 4 dimension lumber (nominal 50 mm X 100 mm X 3.6 m long). Three species groups (Douglas-fir, Hem-Fir. and Spruce-Pine-Fir-South) and two commercially produced machine-stress-rated grades per species group were tested in torsion to determine their shear strength. Incising and preservative treatment produced significant reductions in the average shear strength of Douglas-fir, Hem-Fir, and Spruce-Pine-Fir-South dimension lumber. These effects need to be addressed through the development of more appropriate design values for uses of preservative-treated wood of these species when shear is a governing factor. An adjustment factor of 0.70 is proposed for incised and preservative-treated nominal 2-inch lumber. Close