Four beam types were tested in a pilot study to investigate the feasibility of using 2 by 4 lumber and structural particleboard in 16-foot garage headers. This study compares the performance of each beam type with a double 2 by 12 header, a beam used in house construction for framing a 16-foot garage opening. The study beams, 16 feet 6 inches long and 16 inches deep, were of the ″I″ type cross section using flanges of stress-graded 2 by 4 lumber and webs of one of four materials: plywood; underlayment particleboard; large-flake, phenolic-bonded aspen board; and a urea-bonded mixed-hardwood board. Each beam was nailed-glued at all contact surfaces between the 2 by 4 materials and web stock.
The Forest Products Laboratory (FPL) has promoted healthy forests and forest-based economies since 1901 through the efficient, sustainable use of American wood resources. Early research priorities at the FPL focused on timber testing, wood preservation, wood-based distillates, wood technology, pulp and paper, and wood chemistry. Fourteen scientists and six assistants were initially supported by a total of $28,000 per year. The FPL focused on characterizing the fundamental properties of wood and on wood products utilization. Determining mechanical properties of North American woods and wood products led to practical applications for under-valued species found on National Forest and private lands. Wood preservation, another focus of early FPL research, often aimed to educate industrial wood consumers such as architects and railroad and mining engineers in the ways of efficient utilization. FPL researchers in the Durability & Wood Protection unit are developing new, environmentally preferable wood preservation technologies, including formulations free of toxic metals.
An analysis of hardwood lumber consumption found that demand has changed dramatically over the past four decades as a result of material substitution, changes in construction and remodeling product markets, and globalization. In 1963 furniture producers consumed 36 percent of the hardwood lumber used by domestic manufacturers. Producers of hardwood construction and remodeling (CR) products accounted for an additional 32 percent of hardwood lumber consumption with the bulk of this volume being consumed by manufacturers of hardwood flooring. Between 1967 and 1982 hardwood lumber consumption by furniture producers remained relatively constant. By contrast, lumber demand by CR product manufacturers declined by 33 percent as carpeting was substituted for wood flooring. However, this decline in demand was countered by increased production of pallets and crossties, which accounted for 41 percent of hardwood lumber consumption by 1982. In the 1980s and 1990s overall hardwood lumber consumption surged because of increased lumber use by pallet and CR product manufacturers. Since the late 1990s furniture imports have increased while domestic furniture production has declined, thus furniture manufacturers accounted for only 18 percent of domestic hardwood lumber consumption by 2002. By contrast, consumption by the hardwood millwork, cabinet, and flooring sectors have continued to increase, partially offsetting the decreased consumption by the domestic furniture industry.
This paper examines changes in sawmill concentration and hardwood lumber production for Tennessee between 1979 and 2005. In 1979, only 2 percent of the lumber manufactured in Tennessee was produced by very large mills with capacities of 10 million board feet (MMBF) or more annually. By 2005, such mills produced more than 43 percent of the lumber, generally following an "expand or exit" model of industry concentration. The greatest change in sawmill concentration, however, occurred in the eastern region of Tennessee, where very large mills accounted for 61 percent of the production in 2005 compared to 0 percent in 1979. Construction of mills in eastern Tennessee seems to have been facilitated by relatively low delivered log prices and improved highway systems. Such changes seem to follow a different model of industry concentration, one that occurred during the timber boom of the early 20th century -if timber can be economically transported it will be "severed and sawn." Since 2005 there has been a decline in demand for higher grades of hardwood lumber and large increases in energy costs. This combination could influence the future size, location, operational objectives, and the industrial concentration of sawmills in Tennessee and other eastern hardwood states.
The Global Forest Products Model was used to project international forest sector developments, conditional on the latest RPA Timber Assessment of future domestic changes in the United States. While the United States, Japan, and Europe were predicted to remain major importers of forest products out to 2030, the rapid economic growth of China would make it the world’s largest market for raw wood, and intermediate and final forest products.Mexico and the Republic ofKoreawould also become important markets for solid wood and fiber products. The U.S. share of global exports of industrial roundwood and other paper and paperboard were predicted to increase out to 2030. In competition with the United States, itwas predicted that Finland, Austria, Latvia, Chile, and New Zealand would increase their share of global sawnwood exports, and Austria and the Republic of Korea would emerge as exporters of printing and writing paper.
Environmental accumulation of preservative adjacent to a chromated copper arsenate (type C)-treated wetland boardwalk was evaluated. The site is considered a realistic "worst case" because of the large volume of treated wood, low current speeds, high annual rainfall, and environmental sensitivity. Soil and sediment samples were collected before construction and 0.5, 2, 5.5, 11, 24, 60, and 131 months (11 y) after construction and analyzed for total chromium, copper, and arsenic concentrations. This article updates the findings after 11 years of exposure. Environmental concentrations varied with time, with proximity to the treated wood, and between riparian and aquatic locations. Concentrations of leached components in the soil developed slowly, were greatest at the 60-month sampling, and declined at the 131-month inspection. Soil samples with elevated levels of copper and chromium were confined to directly under the drip line of the boardwalk, and arsenic appeared to be limited to within 0.3 m (1 ft) of the structure. Concentrations of leached components in the sediments increased more quickly than those in the soil and tended to reach maximum or near maximum levels within the first year. However, concentrations of arsenic and copper in sediments directly under the walkway reached maximum levels after 60 months, before declining at the 131-month sampling. Elevated concentrations of copper, chromium, and arsenic were occasionally found in sediments as much as 3 m (10 ft) from the boardwalk.
Consumers choose products based on various tangible and intangible attributes. Previous research has shown that there is a difference between appearance-based and word-based evaluations ofwood species. However, little research has been done on how this difference affects consumer choice. This study examined how the presence or absence of a species name affects a cabinet door's popularity in the Pacific Northwest (including Alaska). The results showed significant difference between appearance-based and species name-based preferences for cabinet doors. For example, respondents chose cherry and red oak cabinet doors more often when the doors were labeled with the species name than when they were not labeled. In contrast, red alder was chosen less often when the doors were labeled with the species name. This suggests that certain species names should be emphasized in cabinet door marketing while others should be avoided. Age and income demographic segments are analyzed and managerial implications are discussed.
Using information from 204 individuals with an active interest in home building and/or furnishing, this study surveys consumers and purchasing agents and reports their reaction to terms used to describe forest products from southeast Alaska. Regarding terms used to describe the trees or forest products, while 67 percent of the respondents would purchase products from old growth trees, purchasing agents were more likely to refuse to purchase products from old growth forests (negative response from 12 percent of consumers vs. 29 percent for purchasing agents). Eighty-eight percent of respondents reacted positively to purchasing products from trees grown under sustainable yield management. Twenty-eight percent of respondents reacted negatively to the term national forest, while the term Tongass received the highest level of uncertainty. When asked if they would purchase products made from trees cut from a forest of concern to either environmental or preservationist groups, respondents showed polarity with approximately equal yes (38 to 46%) and no (43 to 46%) responses. It was concluded that respondents had an overall positive view of Alaska forest products.
The deterioration of heartwood from live and dead Alaska yellow-cedar trees was evaluated by exposing ministakes in soils at field sites in Alaska and Mississippi for 2 and 4 year intervals. Southern yellow pine sapwood served as a control. The vastly greater deterioration, as measured by weight loss, in Mississippi compared to Alaska (60 and 10 percent after 4 years, respec- tively) was attributed to warmer temperatures, a longer growing season, and perhaps the presence of termites. The wood from Alaska yellow-cedar trees dead 26 years did not differ in deterioration from the wood from live cedar trees, but wood from cedar trees dead 81 years experienced an intermediate deterioration between these classes and the pine controls. Slow changes in heartwood chemistry following tree death probably explain these differences for Alaska yellow-cedar. The results from this and several related studies indicate that heartwood from dead Alaska yellow-cedar trees is suitable for many indoor and outdoor applications long after tree death, but wood from live or dead cedar trees does not perform particularly well in contact with soil.
Birch lumber is often characterized by a high degree of knots, bark pockets, heartwood, and other features which force sawmill owners to decide whether to edge and trim boards to produce standard grade lumber vs. proprietary grade character-marked lumber. In addition, the edging strategies used with irregularly shaped flitches can greatly influence cut-stock recovery. To investigate this recovery, 143 kiln-dried 4/4 birch flitches were obtained from a sawmill in south-central Alaska and evaluated by a National Hardwood Lumber Association (NHLA) grader for board grade and lumber tally. Each flitch was marked by the lumber grader, indicating where the board would be edged to produce NHLA grade lumber in a production setting. The flitches were transported from Alaska to Oregon State University where they were scanned to produce digital board data. These data were then processed with the computer simulation program CORY (Computerized Optimization of Recoverable Yield) to estimate the cut-stock yield for various levels of edging severity and sound feature (character mark) inclusion. Four edging strategies were evaluated, ranging from unedged (least severe) to wane-free (most severe). As expected, cutting area recoveries and cutting yields were reduced as edging severity was increased. In many cases, however, these differences were minimal. Cutting yields for clear parts were 21.1, 23.7, 26.2, and 27.1 percent for wane-free, actual, light, and unedged strategies, respectively. Cutting yields for parts that included sound character features increased by more than double to 44.0, 49.0, 52.7, and 54.0 percent for wane-free, actual, light, and unedged strategies, respectively. These results indicate that finding value-added alternatives for this character-marked birch might prove profitable for some Alaskan sawmills that also produce secondary products such as cabinets and furniture or supply cuttings to these manufacturers.
The effects of aligning fibers and of their placement within the fiber mat on strength, elastic modulus, and dimensional stability of high-density, dry-formed hardboard were investigated. This approach was taken to produce hardboards with increase strength for use as structural components. Four sets of oriented fiber configurations and one set of random-formed control boards 3/16 in. thick were prepared from aspen and from Douglas-fir.
Oriented Strandboard (OSB) is a versatile engineered material because the orientation of the strands and the shelling ratio (a measure of weight percentage of the face layer) can be easily changed to modify its properties. This paper reports a model investigation on the influence of orientation level of the strands as measured by percent alignment (PA) and shelling ratio (SR) on linear expansion (LE) of OSB. In general, reduction of LE in one direction is achieved at the expense of LE in the other direction. There is, however, an exception. The analysis showed that if PA is equal in both the face and core layers, increasing PA decreases LE in both directions at the same time if SR is around 0.5. This paper also discusses the LE ratio (LE-Perpendicular/LE-Parallel) in relation to PA and SR. The interdependence of PA in the face, PA in the core, and SR is graphically presented for the control of LE ratio. The ramification of incorporating large amount of fines in the core of OSB, a popular practice in the industry, is also discussed.
This paper uses a previously developed theoretical simulation model to investigate the influence of orientation level of strands as measured by percent alignment (PA), and shelling ratio (SR) (weight percentage of the face layer) on modulus of elasticity (MOE) of oriented strandboard (OSB). As expected, improving PA increases MOE-parallel and decreases MOE-perpendicular, but the decrease of MOE-perpendicular levels off after PA exceeds approximately 50 percent. Increasing SR improves MOE-parallel and decreases MOE-perpendicular, but the change of MOE is negligible after SR reaches approximately 0.7. This paper also shows that orientation level and use of different species in the core only have minimal influence on MOE. Use of MOE-ratio (MOE-parallel/MOE-perpendicular) to estimate PA in the face of three-layer commercial OSB is also discussed.
The primary objective of this project was to develop baseline treatment time data for a hot water bath treatment to meet IPPC phytosanitation regulations for wood packaging material. A second objective was to determine if 100 percent borate penetration could be demonstrated and, if so, the amount of time needed. Pallet-sized material of green red and white oak and yellow-poplar was used. In a worst-case scenario of frozen stringers, the internal temperature requirement was attained on average in 96 minutes. Complete penetration of the borate (as disodium octaborate tetrahydrate-Timbor) was obtained in 24 hours or less.
Amish-made furniture sector maintains its competitiveness during the decline of the US. wood furniture manufacturing industry. Amish-made furniture is an emerging manufacturing sector. More of Amish furniture manufacturers operates at Holmes County, Ohio. It is believed that Amish are only half of the county's population and with 3 percent of Amish employed in the wood sector by 1977, the number increased to 14 percent. Amish furniture sector apply many aspects of competitiveness for the survival of domestic manufacturers with quality craftsmanship and solid wood construction. Amish-made furniture retail stores provides semi-customization, allowing consumers to choose from different species that includes oak, cherry, maple, pine, and walnut. Amish manufacturers presents clustering for short lead times for product customization. Amish manufacturers offers consumers several option on retail floors and enables consumers to buy matching pieces at a later date.
Recycled newsprint (ONP) and dry process aspen fiber were combined with styrene maleic anhydride (SMA) copolymers containing either 7 or 14 percent maleic anhydride. The fiber-filled SMA composites were equivalent or superior to unfilled SMA in strength, stiffness, and notched Izod impact strength. ONP performed surprisingly well as a filler. Unnotched Izod impact strengths for filled polymers were lower than for unfilled polymers. Water sorption was similar among fillers, and was small compared with solid wood.
I.,urnber was sawn Sro~n 150 suppressed-growth ponderosa pine trees, 6 to 16 inches in diameter, harvested near Flagstaff, Arizona. 'l'lris paper presents grade recover and properlies li)r clry 2 by 4's sawn from the logs and graded by a variety of stritclural glading syslerns. Flexural properties met or exceeded those listed in the National Design Specification. When graded as Light Flairling 43 percent of the 2 by 3's made Standard and Better arid as Stmctuial Light Framing, 34 percent made No. 2 and-better. Cb'a~p was the biggest factor limiting grade yield. About 7 percent of the lun~bcr would ~nake a rriachine stress-rated (MSR) lurnber grade of 1450f. bur xith no established market such productio~i is not recomniended. If graded as laminating stock, about 8 percent of the lumber qualified as 1.3 or better. A cornparison of the results froni this study wilh those from a con~paizion study indicates that appearance grades ofl'er the highest vali~e alternative tbl- luinber produced from this resource. Poadams;i pine (PNms po,,rrili,rrta. I..) is ow of the most
Both the disadvantages and advantages of aspen pallet lumber are enumerated. The results of tests are presented on the ultimate impact torsional and shear resistance and the torsional rigidity and shear stiffness of aspen pallet deckboard-stringer joints as well as the static stiffness and impact rigidity of 48- by 40-inch aspen pallets.
Live and Around sawing were compared for the processing of aspen poplar into 1-inch boards and dimension stock. Volume and value yields were obtained from 544 merchantable 8-foot logs. Two types of Live sawing provided lumber and dimension stock yields equal or superior to Around sawing for all log grades.
A high-temperature schedule suitable for drying mixed trembling aspen and balsam poplar, according to grade requirements for maximum moisture content and with acceptably low degrade, was developed in a small laboratory kiln and confirmed in a semicommercial steam kiln. Drying temperatures of 250 degree F dry bulb and 180 degree F wet bulb, with an 18-hour period of high humidity for dissipation of wet pockets, will result in a total drying time of about 96 hours.
This study shows that 1- one-half -inch kiln-dried, surfaced, dimension lumber may shrink in thickness by up to 0. 24 inch. Based on the frequency of occurrence in laboratory tests, these defects can be expected to develop in up to almost 30 percent of each kiln charge. Attention is drawn to the possible adverse effects of these defects on the acceptance of the species group for dimension lumber. More rigorous moisture-content metering is suggested, preferably with an in-line continuous meter, so that wet pockets may be detected.
Experimental aspen waferboards, bonded with liquid or powdered phenol-formaldehyde resins and treated by various methods with a wide selection of preservatives, were tested for fungal resistance in accelerated laboratory trials. Mold growth on the surface as well as weight and strength losses due to the actions of decay fungi were determined. Testing of board strength after decay in high and moderate hazard exposure conditions required modification of decay tests used for solid wood. A range of protection was noted with no preservative system exceeding the efficacy of the inorganic salt formulations. Averaged over all treatments, strength loss and weight loss are well correlated.
