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The work presented here focuses on the, incorporation of an engineered polysaccharide polymer, α-1,3-glucan, derived from the enzymatic polymerization of sucrose, as a performance-enhancing additive for commercial, latex-based wood adhesives used in wood bonding applications. Adhesive performance was measured on hard maple (Acer saccharum) using ASTM Standard Method D-905. Dynamic mechanical analysis and solid-state nuclear magnetic resonance spectroscopy were the characterization techniques used to assess the properties of room-temperature–cured adhesive films. Significant increases in shear stress were observed for these formulated latex adhesives containing the polysaccharide polymer.

Maple and poplar are common names of species that grow in the eastern United States. Physical and mechanical properties were evaluated from small clear wood specimens of hard maple (Acer saccharum) and yellow poplar (Liriodendron tulipifera). Specific gravity, static bending strength and modulus of elasticity, compression parallel and perpendicular to grain, and Janka hardness were tested. The experiments were carried out on defect-free specimens extracted from boards supplied by members of the Staircase Manufacturers Association. The material was donated by companies located in the eastern United States. On the basis of the findings, it can be stated that mechanical properties for maple and yellow poplar have not changed substantially because the average values remain in a range that is very close to the values published in previous studies.

The possibility of the use of thermally modified European beech (Fagus sylvatica L.) in necks of electric bass guitars for the substitution of Hard maple (Acer saccharum) has been studied. The heat treatments were performed at relatively mild treatment temperatures of 140 and 160 °C for 12 h. The acoustic properties were determined by means of experimental modal analysis (EMA) and the mechanical properties by means of static and impact bending tests. The results show that both the acoustic and mechanical, static properties of beech improve significantly owing to thermal modification, being similar or better compared to Hard maple. The impact bending strengths decrease owing to thermal modification. Additional tests on complete necks of electric bass guitars by means of EMA and plucking tests on total instruments show that thermally treated beech at mild temperatures can substitute Hard maple for the use as neck material in electric bass guitars.

Solid wood railway ties have widely been used in the railway system in North America. With decreasing average log diameter and quality, laminated wood railway ties have been developed but used on a very limited scale due to the added cost for adhesive and labour. With significant technological advances made by the wood adhesive industry recently, it is considered timely to investigate the feasibility of fabricating laminated wood railway ties using the new structural adhesives. This study was aimed at developing laminated railway ties using low grade hardwoods to meet the North American performance specifications. A two-component polyurethane structural adhesive was used to bond hard maple (mainly) and yellow birch (limited) lumber of No. 3B Common grade to manufacture 16 ties following four fabricating procedures. The modulus of elasticity (MOE) and modulus of rupture (MOR) of laminated wood ties were evaluated. The key findings were (1) the average MOR of the ties of type A-2 (i.e., laminating first followed by creosote treatment) met the AREMA specifications, however, the average MOE was 3% lower than the required value; and (2) both MOE and MOR of the ties of type A-3 (i.e., CCA treatment first followed by laminating) satisfied the specifications. It is feasible to fabricate laminated wood ties using low grade (No. 3B Common) hardwoods and a proper structural adhesive.

In this article, we report on the effect of internal log defect scanning on the gain in lumber value recovery for five hardwood species, consisting of black cherry, hard maple, yellow poplar, red oak, and white oak logs. A total of 29 logs, 6 logs per species and 2 logs each for log Grades 1, 2, and 3, were scanned with a medical X-ray computed tomography scanner to acquire their cross-sectional images. The one exception being for red oak logs, for which we scanned two Grade 1 logs, one Grade 2 log, and two Grade 3 logs. These logs were then sawn in the sawmill to determine the actual value recovered from each log. Virtual logs constructed with the scanning images of these logs were then sawn on the computer using the TOPSAW software. Based on simple live sawing simulations, overall the average value gain for all species and grades was 46%, while the gains for black cherry, hard maple, yellow poplar, red oak, and white oak were 42, 33, 83, 24, and 60 percent, respectively. The average gains for Grades 1, ...

Between 1963 and 2005 hardwood lumber production in the eastern United States increased by more than 50%. Production more than doubled in the northeastern and north central regions while increasing by less than 25% in the southeastern and south central regions. Increased lumber production in the northern regions was facilitated by an expanding sawtimber inventory, relative high volumes of select oak species and hard maple, an expanding kitchen cabinet industry, increased exports, and increased lumber demand by the pallet industry. Hardwood lumber production in the south central region was correlated with hardwood flooring production. When flooring production declined between 1963 and 1982, south central lumber production declined. After 1982 flooring production increased and hardwood lumber production in the south central region followed. By contrast, lumber production in the southeastern region has been tied to the fortunes of the wood and upholstered furniture industries. As furniture imports increased, the demand for lumber by these industries first stagnated and then declined. As a result, lumber production in this region declined between 1982 and 2005. Today, much of the commodity product portions of hardwood-demanding industries are facing international competition. By contrast, a driver of growth in hardwood lumber demand seems to be smaller manufacturers producing custom and semicustom products. These new industries tend to purchase higher-quality lumber but can use a variety of species. Therefore, states or regions with high volumes of timber and a broad composition of species have the greatest potential for future growth in hardwood lumber production.

The eastern hardwood resource contains numerous species that differ in grain, color, texture, and workability. Because the value of hardwoods is derived from appearance, these variations in physical attributes can cause the price for identical grades of hardwood lumber to vary by as much as 600% between species. As a result, there is incentive for primary processors to harvest certain species more intensively than others, which could affect long-term forest composition. This article introduces the concept of relative utilization to augment the infrequently published annualized growth-to-drain ratio and examines the relative utilization of 13 eastern hardwood species on a national and regional basis. An analysis of relative utilization coefficients developed from primary and secondary data showed that black cherry, red oak, hard maple, and yellow-poplar were relatively overutilized, while the gums, hickory, and beech were underutilized. Relative utilization has varied by species over time due to changes in furniture styling and the ability of industry to substitute species. Shade-tolerant species such as hard and soft maple are regenerating faster than shade- intolerant species, resulting in increased long-term supply even if current sawtimber volumes are relatively overutilized. North. J. Appl. For. 18(2):37–41.

The climatic conditions during container shipment of color sensitive veneer logs (hard maple and black cherry) were documented using a computerized data-logger.