Abstract
Aboveground field performance data are needed to help users select appropriate materials, assist in the development of evidence-based codes and standards, and support the development of new export markets. A review of the literature in the early 2000s revealed that there was very little hard data on the performance of North American naturally durable wood species, particularly for aboveground applications. Field tests of six Canadian wood species reputed to have moderate to high natural durability were therefore installed in test out-of-ground contact in the autumn of 2004 and spring of 2005 at two test sites in Canada and two in the United States. Decay results are reported after 10 years. The test site with the fastest aboveground decay rate was in Hawaii. Above ground, yellow cedar (Callitropsis nootkatensis) and western red cedar (Thuja plicata) were the most consistently durable at all four test sites. However, it would not have been possible to predict the relative performance of naturally durable species in one climate and location from their relative performance in another climate and location. The presence of sapwood was associated with more severe decay, although it was unclear whether the presence of sapwood increased the risk of decay in the adjacent heartwood. There was no substantial difference between decay in old-growth and second-growth samples above ground. The presence of a coating applied to decking had some protective effect against decay at the less aggressive test sites.
Abstract
Black walnut (Juglans nigra) is one of the most important tree species in the United States for producing lumber and other forest products. However, a recent outbreak of thousand cankers disease vectored by the walnut twig beetle (Pityophthorus juglandis) threatens the population of black walnut in the United States. Infected walnut trees are typically removed to prevent spread of the vector, resulting in large quantities of potential sawlogs that must be sanitized. The objective of this study was to identify the temperature and time combination necessary to heat treat infested materials to 100% beetle mortality. Testing was done on infested sample blocks that contained sapwood and bark. The specimens were heated to various temperatures and examined, both through emergence chambers and destructive sampling, for the presence of P. juglandis at any life stage. Results of the study indicate that heat treating black walnut products to 50.1°C at a depth of 3.8 cm (1.5 in.) for 30 minutes will result in 100 percent beetle mortality. As a side product, this study also produced 3,000 board feet of rough-cut lumber. These boards were heat treated and sold, following the protocol developed in this study. This study demonstrates that wood from black walnut trees infected with thousand cankers disease can be effectively heat sterilized and utilized, reducing the need to chip, landfill, or otherwise dispose of the material without economic return.
Abstract
Surface coatings of melamine-modified urea-formaldehyde resins (MUFs) containing ammonium polyphosphate (APP) have been shown to significantly improve the fire retardancy of wood by prolonging the ignition time and reducing the heat release rate, total heat released, and mass loss rate. Dual protection of wood against both decay and fire has been proposed for remedial situations and interior construction. In this study, the fire retardant MUF resin type 3 (MUF3)/APP mixture system showed strong activity against wood decay fungi via an activity inhibition test. Two species of wood were subjected to steeping with the fire retardants MUF3/APP. The treatments were evaluated for fire and decay resistance using cone calorimetry and fungal decay resistance tests. The results showed that MUF3/APP surface treatment can provide dual protection to wood against degradation by decay fungi and fire.
Abstract
The present research was performed with an aim to develop an alternative preservative treatment method for marine- and shuttering-grade plywood. Per Indian Standards, 12 kg/m3 of retention is required in marine- and shuttering-grade plywood, which is very difficult to achieve. The higher loadings of wood preservative chemical are being achieved only by the pressure impregnation method. The pressure impregnation method requires energy to run the equipment, skilled manpower, and sophisticated instruments; a large amount of damage takes place to the plywood during the process. Hence, an alternative to this glue-line poisoning followed by hot and cold dipping of plywood has been found suitable to achieve the 12 kg/m3 of retention without affecting the glue and plywood properties.
Abstract
The present study investigated the effect of various types of impregnating and surface treatment materials on the fire resistance of wood material indoors and outdoors. Wood samples (Cedrus libani A. Rich.) were impregnated with Wolmanit-CB or Tanalith-E according to ASTM D1413‐76 (American Society for Testing and Materials 1976). The impregnated surface was treated with either synthetic or water-based outdoor varnish materials. The impregnated and varnished samples were left in outdoor conditions for 1 year. The combustion characteristics of the samples were investigated at the end of 1 year according to the combustion parameters detailed in the ASTM E160‐50 (1975) combustion test. The results of this study indicated that the combustion parameters were lower in the 1-year-old samples (89.12% of control values), in the samples impregnated using Wolmanit-CB (89.18% of control values), and in samples treated using water-based varnish (88.43% of control values). The analysis of flue gas indicated that the O2 content of the 1-year-old samples impregnated with Wolmanit-CB and treated with synthetic varnish was higher, whereas the CO content was lower. In conclusion, impregnated Wolmanit-CB specimens provide higher fire resistance.
Abstract
Using wooden waste as insulation material benefits society by using waste products, reducing building thermal load, and sequestering carbon dioxide. In this study on heat insulating materials, a novel low-density wooden mat was fabricated from wood shavings and kenaf fibers. This research addressed the influences of fabrication conditions on the thermal conductivity and volumetric specific heat of the materials used. The raw materials (wood shavings and kenaf fibers) were mixed with a binder component, and the mixture was thermoformed. The thermal conductivity and volumetric specific heat of the mats were measured, and the influence of mixing ratio, density, and heat flux was evaluated. The results demonstrated that thermal conductivity was largely affected by the mat density and mixing ratio but was largely unaffected by changes in the heat flux. The volumetric specific heat of the mats was largely unaffected by the raw material mixing ratio but was greatly affected by the mat density. The tendency of the thermal conductivity decrease was changed according to the combination ratio of the wood shavings and the kenaf. The wood shavings are flake shaped and curled, and the kenaf is fibrous. It was thought that the internal void was made smaller effectively by mixing two different shaped fibers and the thermal conductivity was minimized. As a result, the thermal performance of the subject mats, as compared with glass wool, exhibited a slightly lower thermal insulation level and higher heat capacity. The results are important in improving efficiency and the commercial design of insulation materials.
Abstract
Superheated steam vacuum drying shows major advantages in terms of reducing the boiling point of water and speeding up the drying process, but to our knowledge, no researcher has addressed the effects of drying conditions on heat transfer characteristics during superheated steam vacuum drying of wood. In this study, we did so using fast-growing poplar. Temperatures inside the wood were measured and the convective heat transfer coefficients calculated under temperature conditions of 35°C, 55°C, and 70°C and absolute pressures of 0.03, 0.06, and 0.1 MPa. The results of our subsequent analysis showed that the ultimate temperatures inside wood increase alongside increasing absolute pressure at the set temperature conditions and are lower than that of the drying medium. In addition, we found that convective heat transfer coefficients increase as absolute pressure increases at the set temperatures and also increase as temperature increases at set absolute pressure conditions. We then established a convective heat transfer coefficient model based on the experimental results. The findings presented here may provide theoretical guidance for maximizing the available advantages of superheated steam vacuum drying and choosing appropriate drying schedules for poplar in future applications.
Abstract
Polyphenolic chemical compounds were extracted from merbau (Intsia spp.) wood with an aqueous medium at a 1:4 ratio (wt/wt) heated to 80°C for 3 hours. The extracted compounds were characterized by matrix assisted laser desorption ionization time of flight spectrometry and included oligomers with up to six repeating flavonoid units, with resorcinol being the dominant compound paired with a minor amount of catechin units. The extract had a Stiasny number of 92.4 percent. The extract was combined with formaldehyde to produce a resin that was used to manufacture five-layer glued laminated lumber using four wood species, namely, pangsor (Ficus callosa), mindi (Melia azedarach), pine (Pinus merkusii), and mangium (Acacia mangium). The modulus of rupture and shear strength of mangium glued laminated lumber met the requirements of the Japanese standard (“Japanese Agricultural Standard for Structural Glued Laminated Timber,” 2003), and all products had a low formaldehyde emission.
Abstract
The fiber and chemical properties of Dendrocalamus giganteus at three ages from three different sites in China were investigated. For samples from all sites, the fibers in the middle internodes of culms were longer than those of other internodes. A similar trend was also observed within one internode. The fiber achieved its maximum length after 1 year, but the maximum length differed with site. The chemical composition and fiber characteristics also varied with height and site. Bamboo culms at the age of 3 years were suitable for utilization purposes, and the bamboos of Cangyuan provenance were the best for pulping and processing. They were also more suitable for popularization as a timber-yielding type owing to having the longest fibers and the lowest ratio of wall thickness to lumen diameter, the lowest SiO2 and lignin contents, and the highest holocellulose content.
Abstract
Presently there is a lack of information describing US southwestern energy consumption and emissions generated from the sawmilling industry. This article uses a mail survey of softwood sawmills in the states of Arizona, Colorado, and New Mexico to develop a profile of on-site energy consumption and selected emissions for the industry. Energy consumption is categorized by fuel type on a production basis for both renewable and nonrenewable sources for production year 2012. Selected emissions from on-site energy consumption were also estimated for respondent sawmills. Survey respondents represented 35 percent of total softwood lumber production of 169.2 million board feet. Total annual on-site sawmill energy required was 64.8 billion British thermal units. Sixty-one percent was derived from diesel fuel, primarily for on-site rolling stock; 35 percent was from electricity; 3 percent was from gasoline used for on-site rolling stock; and the remainder was from propane and wood. Energy produced from nonrenewable sources accounted for 94 percent of total on-site energy consumption. Off-site electricity generation for consumption at sawmills comprise the majority of all emissions in this analysis: 62 percent of CO2, 99 percent of CH4, 94 percent of NOX, 99 percent of SOX, and 99 percent of particulate matter ≤ 10 μm (PM10). Diesel fuel, which supplies the majority of on-site energy, comprises 36 percent CO2, 0 percent CH4, 5 percent NOX, 0.4 percent SOX, and 1.1 percent of PM10.
Abstract
Contaminated storm-water discharge is a growing concern in the United States owing to a steady increase of harmful pollutants entering freshwater sources. This study remediated contaminated storm-water runoff from a bio-oil conversion facility through a simulated constructed wetland. A six-phase series of constructed wetlands was contaminated with varying dilution levels of bio-oil process water. The study concluded that there was a significant decrease in biological oxygen demand (BOD) and microtoxicity over a 10-day remediation cycle within the constructed wetlands for the lower levels of contaminated storm water. The higher levels of contamination changed very little in total volume of pollution. A comparative screening of the bacterial community within the wetlands during the contamination process showed a similar trend in species richness and composition for the first three phases of contamination. There was a shift in richness and diversity for the final three phases of contamination after 10 days. The constructed wetlands were successful at lowering BOD and toxicity levels and achieving permissible pH levels at dilutions higher than 500 times. When the concentrations of contaminated water were lower than 830 mL of contaminated bio-oil wastewater for every 240 liters of rainwater, the constructed wetlands were successful only at achieving permissible pH discharge levels. Better results for high-level contamination may be achievable with longer residence time in the wetlands.
Abstract
The use of social media as a marketing tool has increased significantly in recent years. However, limited information is available regarding social media use in the US forest products industry or social media adoption at the organizational level, especially within the business-to-business context. This study presents part two of a two-part series of articles that look at the forest products industry in the digital age. A mail survey was conducted in 2013 to examine factors affecting the use of social media in the US forest products industry. This article also looks at the perception of forest products companies regarding social media effectiveness and identifies challenges faced by the forest products companies regarding social media use. Results show that close to 58 percent of respondents currently use some form of social media. The most common social media tool implemented was Facebook. Respondents' adoption of social media was influenced by company age, net sales revenue, product type, Web site content, perceived importance of e-commerce, and perceived ease of use of social media as a marketing tool. About 94 percent of the respondents thought that social media was an effective tool for marketing. Although no major concerns were expressed regarding the use of social media, there was some concern about generating the return on investment to cover the costs associated with social media use. The information collected from this study can be used in assisting the forest products industry in understanding the world of social media marketing and developing an effective social media marketing strategy.
Abstract
The use of woody biomass as a feedstock for wood-burning energy facilities and pellet mills has increased across the southern United States in recent years. Feedstock for these facilities comes in a variety of forms, including roundwood, logging residues, and mill residues. Precommercial thinning (PCT) of pine stands is sometimes used to mitigate southern pine beetle (Dendroctonus frontalis) risk that traditionally incurs added cost to landowners. Utilization of biomass from PCT for biomass energy production may provide an opportunity to reduce the costs of southern pine beetle risk mitigation practices. Potential use of PCT biomass has been suggested in previous studies, but little effort has focused on quantifying amounts available for utilization. Using a list of nonindustrial, private forests enrolled in the Virginia Department of Forestry Pine Bark Beetle Prevention Program, we conducted inventories of pine stands scheduled to undergo PCT to estimate potentially harvestable biomass. Inventories of stands in the 5- to 7-year-old and the 8- to 12-year-old age groups showed average volumes of 14.47 and 39.63 green tons per acre of biomass, respectively. Results suggest that PCT stands in the 8- to 12-year-old age group may contain sufficient volumes for economically feasible harvests based on removal estimations, thinning costs, and regional biomass prices. The feasibility of such harvests will largely depend on the degree to which harvesting costs are affected by utilizing the small-diameter stems typically found in PCT stands and local demand for biomass.
Abstract
Communication is an important tool in maintaining legitimacy and acceptability of forest sector operations and activities, and expectations by the general public on the forest sector conduct in Europe are in general very high. Despite this, there is scarce research in cross-national contexts on how forest sector sustainability is communicated to the general public and what development areas can be identified in terms of communication content. This study applies a qualitative content analysis in four forestry-rich European countries (Austria, Finland, Germany, and Slovenia). The state of online communication of 61 companies and 19 industry associations was qualitatively analyzed in 2014 with a focus on eight core sustainability topics of interest that were identified via an international forest sector stakeholder feedback process. Our results show some great similarities, but also some interesting differences in terms of communication frequency and weight of hot topics across countries. The most frequently communicated area was economic contribution of forests (in Finland and Austria), followed by debate over forest conservation versus production (Germany) and the concept-added value of wood (in Slovenia). With the exception of Slovenia, the role of forests in combating global warming was emphasized more frequently within industry associations than among individual forest industry companies. Characteristically, current content of sustainability communication focuses on supplying factual information. Thus, there is a need for developing more targeted and bidirectional forms of stakeholder communication in the future, emphasizing also more active use of social media channels and empowering organizations to promote interactive communication and collaborative learning.
Abstract
The goal of this study was to integrate forest management practice with the mechanical properties of oriented strand board (OSB). Modulus of elasticity (MOE), modulus of rupture (MOR), and internal bond strength (IBS) were determined from OSB panels made from control, thinned, and fertilized trees. Different trends were associated with growth ring counts and heights of the feedstock trees. The mechanical properties were not dependent on the density profiles. MOE and IBS from the different forest managed trees were strongly correlated with different anatomical structures. However, the MOR of panels made trees from different forest management schemes was not strongly correlated with any anatomical structures but was strongly correlated with MOE.
Effect of a Water Repellent on Moisture Intrusion Patterns in Small-Scale Mass Ply Panel Floors
Regional Drivers of Primary Wood Processing Mills in the Western Southeast US
Hardwood Sawing Costs: Log Size Differences and Sawing Strategies
Effect of Incising on Flexural Properties of Nominal 4 by 6-Inch Douglas-Fir
Effect of Decoration Complexity and Age on Aesthetic Evaluation, Purchase Intention, and Visual Attention in Wood Furniture
Study on Urea-Formaldehyde Prepolymer and Hot-Press Treatment of Italian Poplar Wood
Vermont Stumpage Price Trends Revisited: With Comparisons to New Hampshire
Demonstration Results from Greenhouse Heating with Bio-Oil
Potential Use of Deformed Shank Nails as a Solution to Annoying Vibrations in Wood Floor Systems
eISSN: 2376-9637 | ISSN: 0015-7473