Rapid discoloration and checking of wooden surfaces when exposed outdoors has caused wood to fall out of favor as an outdoor building material, especially in applications where appearance is important. The surface appearance of wood products exposed outdoors can be improved through the application of film forming coatings or by...
Engineered wood composites are used in many structural applications and are intended for dry use. However, these materials may encounter significant amounts of wetting while in service, which can lead to structural failures. This study combined aspects of wood science, mechanics, structural engineering, and mycology to assess changes in material...
Western juniper and cinnamon essential oils were combined with ethanol at 2.5, 5, and 10% concentrations by weight and applied to hybrid poplar (Populus trichocarpa x P. deltoids) veneers by vacuum soaking to produce a naturally durable wood veneer with increased mechanical properties for use in structural composites. Half of...
The effects of incorporation of selected biocides on physical and mechanical properties of aspen strandboard were assessed using five copper-based preservatives or zinc borate at three retention levels. Tebuconazole or 4,5-dichloro-2-N-octyl-4-isothiazolin-3-one (DCOI) were added as co-biocides to selective copper-based treatments. Mold box tests showed that only panels treated with DCOI...
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JefferyJ. Morrell Frederick A. Kamke
The effects of incorporation of selected biocides
The links between forests, streamflow, and climate are poorly understood. Despite hundreds of studies over the past 60 years, fundamental questions of forests' effects on the hydrologic cycle remain unanswered. The hydrological cycle involves mutually-dependent biological and physical processes that operate at multiple scales of time and space, and this...
Plywood panels collected from thirty seven mills located
throughout the Pacific Northwest they were treated with chromated copper
arsenate Type C (CCA-C) or ammoniacal copper zinc arsenate (ACZA) using
modified full cell and full cell processes respectively. Preliminary
tests were performed to determine plywood sample size, replication, and
treating schedule....
The ability of the fluorescent-coupled lectins wheat germ
agglutinin (WGA) and concanavalin A (Con A) to react with selected
Basidiomycetes, Ascomycetes, and Fungi Imperfecti was evaluated using
pure cultures of thirty-five fungi grown on malt extract agar. WGA,
which is specific for residues of N-acetylglucosamine present in fungal
chitin, reacted...
Experiments investigated how the fumigant methylisothiocyanate
(MIT), Douglas-fir wood at various moisture contents (MC), and the
wood decay fungus Poria carbonica Overh., interacted to govern
overall fumigant effectiveness.
MIT decomposed in wood to form non-MIT residues at rates of
about 0.16%, 0.9%, and 1.6% of the total bound MIT per...
This research examined the potential for using peanut husk as a fiber alternative to wood in the production of melamine-formaldehyde (MF) particleboard. MF resin was used to produce panels with one, three, six, nine or 12 percent resin contents. Modulus of Rupture (MOR), Modulus of Elasticity (MOE), Internal Bond (IB)...
The sustainable use of wood for rail ties requires chemical treatment to increase service life and maintain structural integrity. Treatment can only be applied after lengthy air-seasoning to reduce moisture content in wood, but seasoning leaves ties exposed to attack by decay fungi for up to a year. One factor...
Boron and boron compounds have been long used for pressure treatment, dip-diffusion, and remedial treatments of wood because of their proven efficacy against fungi and insects. These materials are especially attractive because their high water solubility promotes deeper penetration into wood. Other useful properties of boron include its neutral pH,...
Resistance to moisture uptake is an important attribute of some wood preservatives and can help reduce moisture cycling that leads to the development of deep checks. While the potential for preservative treatments to help improve wood/moisture interactions is acknowledged, there are no tests that specifically evaluate this performance parameter. Checking...
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Jeffrey J. Morrell
Resistance to moisture uptake is an important attribute of some wood
Copper is the most common ingredient in waterborne preservatives and provides excellent activity against most fungi and insects. However, issues associated with copper migration from treated wood have created increasing concerns about potential risks to non-target organisms in surrounding environments, especially those in sensitive aquatic environments. Various Best Management Practices...
The goal of this project was to develop an integrated pest management strategy
for the control of a powder-post beetle (Dinoderus minutus F.). This species causes
serious damage in Philippine bamboo. Developmental threshold and thermal constants
were examined and natural enemies and ftmgi associated with beetles were investigated.
Finally, the...
Supercritical fluid (SCF) impregnation is a promising preservative treatment method, however, the development of SCF processes has been slowed by a limited understanding of the process. Developing a better understanding of the effects of various process parameters on treatment results would allow for a more rational development of SCF impregnation....
Copper is an excellent biocide which has a long history of usage for protecting wood from deterioration, but some organisms have developed tolerance for this chemical. Copper tolerance among wood decay fungi is a poorly understood phenomenon that is gaining importance as cofactors such as arsenic and chromium are removed...
Moisture intrusion in residential structures can lead to substantial fungal decay and this damage costs billions in repair/replacement costs. The extent of damage and the rate at which it occurs are primarily dependent on the wood moisture content and temperature in the structure. Determining the risk of decay for various...
Small size wood assays were utilized to study the
effect of added nutrients to the wood on the interactions
of Trichoderma harzianum Rifai and two wood decay fungi,
Trametes versicolor (white rot) and Gloeophyllum trabeum
(brown rot). Weight losses related to time of exposure
were monitored as a measure of...
Biological stain (blue stain) reduces wood value and
prevents its use in many structural applications. Increasing
environmental concerns have restricted the chemicals
available for controlling this damage. As a result,
biological control has received more interest. The
application of these systems to wood has been limited due to
their inability...
The fungi that cause mold and stain of freshly sawn lumber result in millions of dollars in losses to the forest products industry. Stain and mold are typically prevented by either kiln drying or by application of a topical fungicide. While these treatments are effective, kiln drying is costly and...
The biocontrol potential of Trichoderma harzianum strains
B-2A, B-8A, B-4B, B-15B, and B-41 and Serratia plymuthica was
evaluated using agar plates and wood wafers of unseasoned
ponderosa pine (Pinus ponderosa laws). All five isolates of
Trichoderma harzianum and Serratia plymuthica could inhibit
stain fungi growth in agar plates and exhibited...
Pest control operators in Oregon were surveyed to examine the occurrence of carpenter ants and other wood destroying organisms in structures. Carpenter ants frequently occurred in the coast and Willamette valley regions of the state and were associated with wetter, mesic habitats. To examine the effects of substrate and moisture...
Two approaches to improving wood treatability include the modification of pressure
schedules during conventional liquid treatments and the use of supercritical fluids (SCFs). In
both of these techniques, pressure differences are important for transporting materials into
wood. The level of pressure and its change during SCF treatments are also important...
Basamid^R (3,5-dimethy1-1,3,5,2H-tetrahydrothiadiazine-
2-thione) is a crystalline powder used as a soil sterilant.
This fumigant acts in soil by decomposing to methylisothiocyanate
(MITC), the primary active ingredient, as well as
hydrogen sulfide, methylamine, and formaldehyde. In wood,
Basamid decomposes too slowly to be efficacious against
decay fungi unless amended with various...
Metham sodium or NaMDC is one of the four major soil
fumigants that are currently registered for controlling
internal decay of wood products in use. Fumigants are used
primarily in utility poles but are also applied to piling,
timbers and other large wood members.
NaMDC must decompose to fungitoxic compounds...
Over-the-counter (OTC) wood preservatives can provide wood with both a moisture barrier and fungicidal protection against biodeterioration, yet there is little comparative data on the performance of these preservatives. In this study, the potential of various low-toxicity, OTC preservatives was evaluated on five western wood species, western red cedar (Thuja...
In spite of the lack of accurate information about the
treatability of western wood species with waterborne wood
preservatives, consumption of these products continues to
increase. Western wood species, notably Douglas-fir, are
notoriously difficult to treat with waterborne systems, yet
there is relatively little data on the effects of wood...
Studies of physiological effects of fungicides on fungi are critical for understanding
modes of action and mechanism of resistance; however, studies are difficult to perform
on filamentous fungi because of the inability to produce homogeneous a biological
system using a mass of mycelium. Moreover, the presence of rigid cell wall...
The potential of 9 bacterial and 6 fungal isolates to
protect wood against wood staining microorganisms was
studied using small sapwood samples of unseasoned Ponderosa
pine [Pinus ponderosa Laws] sapwood. Bacillus subtilis Cohn,
isolate 733 A , Gliocladium virens J.H. Miller, J.E. Giddens
& A.A. Foster isolate H 3 and...
The biocontrol potential of Trichoderma harzianum Rifai,
Trichoderma polysporum (Link.:Pers.) Rifai, Scytalidium aurantiacum
Klingstr. et Beyer or a Penicillium sp. against Trametes versicolor
(L. :Fr.) Pilat, Neolentinus lepideus (Fr.) Redh. et Ginns, Postia
placenta (Fr.) M.Lars. et Lomb. and Irpex lacteus Fr. was evaluated
using agar plate, soil bottle and...
While microbial colonization of wood is presumed to be characterized by a myriad of interactions between numerous organisms, studying these processes is often difficult owing to the opaque nature of the wood and the inability to readily distinguish among the many species colonizing the material. One method for enhancing the...
Copper migration from treated wood has created concerns within the
environmental community because of the potential effects of this heavy
metal on aquatic organisms. Migration can be limited, to some extent, by
more controlled treatments and by post-treatment processing, but these
actions cannot completely overcome the problem. An alternative approach...
New species introductions have been associated with the movement of
people for thousands of years. For instance, horses were introduced into North
America by Spanish explorers, while pigs were introduced by the Polynesians
into many Pacific islands long before the establishment of permanent
European settlements. Both of these species introductions...
Fungi are the primary biological agents of wood deterioration and cause major economic losses of wood products globally. Wood in outdoor applications tends to remain wet for extended time periods, making it susceptible to fungal attack. Understanding the factors involved in fungal colonization of wood is important for developing improved...
There are over 130 million wood poles supporting electrical transmission and distribution lines in the U.S. The vast majority of these poles are preservative treated to prolong their useful life. In some cases, however, the depth of treatment is relatively shallow, leaving a deep zone of moderately durable, untreated heartwood....
This study seeks to determine the feasibility of
utilizing one vaporizable copper compound - bis-[1-
(dimethylamino)-2-propanolato] copper(II) (Cu(DMAP)₂ as a
potential wood preservative. The synthesis of Cu(DMAP)₂
was conducted in accordance with a method developed by
Buhro and Dingman, Washington University, St. Louis,
Missouri. The yields of Cu(DMAP)₂ synthesis were...
The goal of this study was to optimize a through-boring pattern that will provide adequate preservative penetration while minimizing the reduction in overall pole bending strength. Hole spacing was developed using longitudinal and transverse chemical penetration data from previous studies. Finite element analysis was used as a preliminary assessment tool...
It is difficult to treat the heartwood of many wood species with liquid preservatives using conventional liquid processes. Supercritical fluids (SCF) used as carriers of preservatives to impregnate refractory wood species may be an attractive alternative to conventional liquid carriers. While SCF impregnation has many potential advantages, some wood species...
Wood plays a key role in modern electrical infrastructure; crossarms and power poles utilize the high strength to weight ratio, availability and low cost of wood to facilitate the access of power to millions of Americans. However, wood presents a variety of challenges as a material. In structural applications, one...
Natural durability remains one of the most attractive characteristics of wood, and helps wood obtain a premium price. A worldwide shift towards the use of younger trees from intensively managed forests has created greater concerns about wood quality, especially the wood’s resistance to fungi and insects. Wood durability is assessed...
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Jeffrey J. Morrell
Natural durability remains one of the most attractive characteristics of
Phytophthora ramorum is a plant pathogen that was accidentally introduced to the United States. This invasive microorganism has killed over a million trees in California and Oregon, and continues to spread to new areas. Diseased areas have been nationally quarantined to prevent further spread and more than ninety countries include...
Logging and forest thinning operations generate large amounts of residues in the form of small trees, branches and foliage that are usually left on the ground to decay or are burned. These resources are readily available, but it is uneconomical to remove them from the forest. The potential utilization of...
The Pacific Northwest is blessed with an abundance of precipitation. This rainfall, however, can have important consequences for industries that must process the resulting stormwater for proper discharge. This is particularly true of wood treatment facilities. Past management practices at wood preserving facilities located in the Western United States create...
Heartwood can have properties that are distinct from sapwood,
including resistance to insect and microbial attack. Despite the practical
importance of heartwood formation in trees, a review of the literature revealed
that little was known about the effects of environmental factors on heartwood
quality or how variations in heartwood properties...
In investigating wood treatment as a possible processing option for Alaska forest products manufacturers, the double-diffusion method using sodium fluoride followed by a copper sulfate appeared to be the most advantageous approach. Yet, little information was available as to the chemical retention after treating and its resistance to leaching. Green...
This study examined the decay resistance of the pine and maple components of wood plastic composites (WPC' s) of varying thicknesses exposed on several culture media to wood decay fungi under laboratory conditions. The ability of malt agar extract (MEA), potato dextrose agar (PDA), amended basal salts, sawdust (maple and...