Abstract

Wood products have many environmental advantages over nonwood alternatives. Documenting and publicizing these merits helps the future competitiveness of wood when climate change impacts are being considered. The manufacture of wood products requires less fossil fuel than nonwood alternative building materials such as concrete, metals, or plastics. By nature, wood is composed of carbon that is captured from the atmosphere during tree growth. These two effects—substitution and sequestration—are why the carbon impact of wood products is favorable. This article shows greenhouse gas emission savings for a range of wood products by comparing (1) net wood product carbon emissions from forest cradle–to–mill output gate minus carbon storage over product use life with (2) cradle-to-gate carbon emissions for substitute nonwood products. The study assumes sustainable forest management practices will be used for the duration of the time for the forest to regrow completely from when the wood was removed for product production during harvesting. The article describes how the carbon impact factors were developed for wood products such as framing lumber, flooring, moulding, and utility poles. Estimates of carbon emissions saved per unit of wood product used are based on the following: (1) gross carbon dioxide (CO₂) emissions from wood product production, (2) CO₂ from biofuels combusted and used for energy during manufacturing, (3) carbon stored in the final product, and (4) fossil CO₂ emissions from the production of nonwood alternatives. The results show notable carbon emissions savings when wood products are used in constructing buildings in place of nonwood alternatives.

Abstract

Pallets are one of the basic building blocks of supply chains. Pallets are the most common unit-load platform used across the world and allow for efficient and seamless handling, storage, and transportation of goods. Every year, 500 million new pallets are manufactured and become part of the large pool (roughly 2 billion) of pallets that are in circulation in the United States. Wood remains the most common pallet material, accounting for more than 90 percent of the inventory and applications worldwide. As companies strive to become more sustainable, a thorough understanding of the environmental impacts of every aspect of their logistics operations becomes critical. Among the many factors affecting the life cycle of wood pallets are the pallet structural design, logistics management approach, and service environment conditions. This work is the result of a comprehensive 2-year study on the operations and practices that take place during a wood pallet life cycle. In this article, a prescribed approach for estimating the carbon footprint, or greenhouse gas emissions, that arise across all phases of a pallet life cycle, is presented. In addition, the impact of contributing materials, processes, and activities in each phase is quantified. The findings presented in this article provide a foundation to guide strategies on pallet design and returnable container network and policy design.

Abstract

Some forest products companies have enrolled in forest certification and chain-of-custody certification programs due to a perceived increase in demand for certified products. The results of studies on certification conflict in regard to whether certification provides a competitive advantage and enhances market access. There is a lack of information regarding forest industry perceptions of forest certification, including potential barriers and challenges. To address these shortcomings, a survey was mailed to forest products manufacturers in Virginia to study their opinions about forest certification. The majority of respondents believed there were few benefits to certification programs; in particular, a majority perceived limited to no benefit with regard to market share, exports, future demand, and gaining a competitive edge. A similar number also reported that they associate little to no environmental benefits or improvements to company image associated with certification. The top barriers to certification identified by forest products manufacturers were that certification systems do not add value to their products and there is a lack of certified raw material.

The top challenges that certification faces in regard to acceptance by manufacturers included limited to no perceived financial benefit and lack of market demand. The barriers and challenges identified will likely have to be overcome to increase the number of firms enrolling in certification programs.

Abstract

The net value of hardwood trees (dollars per tree) is thought to increase with stem size for three reasons. First, large trees yield a greater volume (cubic meters) of logs, which tend to be larger than logs from small trees; second, large logs are more valuable (dollars per cubic meter) than small logs; and, third, large logs cost less (dollars per cubic meter) to process than small logs. Yet few studies have assessed both the cost of processing hardwood trees and the value of their products. In this article, we examine how the net value of sugar maple trees (Acer saccharum) varies with tree size and the presence of defects, such as fungi and seams. We quantify the gross value of firewood, lumber, and residues as well as the costs of harvesting and sawmilling. For each tree, we also calculate its net value to an integrated forestry company by subtracting costs from gross values. Our results confirm that large trees are more profitable than small trees but challenge current assumptions as to why. As expected, the volume and value of products are reduced by defects, while costs (dollars per cubic meter) are lower for larger trees. However, we found that gross value (dollars per cubic meter) does not vary with tree size, indicating that large trees yield more but not necessarily better products. The results of this study provide insight into how loggers can improve value recovery while limiting processing costs. These results also challenge the rationale behind silvicultural prescriptions that retain large trees based on the assumption that they produce greater volumes of higher-quality wood.

Abstract

Antimicrobial fabric is increasingly used, and could eventually be required, in garments that are in direct contact with the human body, an environment that is ideal for microbial growth. Forest species such as Cassia fistula, Pongamia pinnata, Tectona grandis, and Jatropha curcas represent major groups of antimicrobial agents, which consist of active phytochemical constituents and can be used as antimicrobial agents for applying special finishes on textiles. In the present study, qualitative and quantitative screening of leaf extracts of forest species was carried out. Leaf extracts of C. fistula, P. pinnata, T. grandis, and J. curcas were prepared using solvents, viz., ethanol (70%), methanol (70%), choloroform, and deionized water. Extracts were determined for the presence of phytochemicals. Results of phytochemical screening revealed the presence of alkaloids, flavonoids, and tannins in all the leaf extracts of selected forest species. However, the saponins were absent in P. pinnata and J. curcas leaf extracts, and terpenoids were absent only in P. pinnata extracts. Further, the total phenolic content (TPC) was evaluated using the Folin-Ciocalteu assay method, whereas total flavonoid content (TFC) was analyzed using the colorimetric method. Methanolic extracts of T. grandis, P. pinnata, and C. fistula exhibited the highest TPC and TFC in the increasing order 143.74, 161.53, and 228.08 mg, and 126.21, 148.33, and 179.1 mg, respectively, while J. curcas exhibited high amounts of TPC and TFC content in ethanolic extract. We therefore conclude that extracts from forest species such as C. fistula, P. pinnata, T. grandis, and J. curcas can be used for applying eco-friendly and healthy finishes to textile substrates.

Abstract

Utilization of biomass from logging residues for renewable energy production depends on forest harvesting businesses. As biomass markets emerge, businesses will need to adapt to meet operational requirements. Logging businesses that supplied biomass for energy production in Virginia were surveyed regarding operations and attitudes. Results show that businesses across a broad range of total production levels (150 to 6250 tons/wk) harvested biomass and roundwood using integrated harvesting operations with whole tree chippers. Businesses had produced biomass an average of 6.8 years. Sixty-one percent of operations utilized a single loader at the landing for processing roundwood and biomass. Biomass accounted for an average of 28 percent of each respondents total reported production and was often produced with relatively large (median = 600 horsepower) chippers with an average age of 12.5 years. Characteristics of operations where business owners agreed they profited from biomass production were compared with those that were neutral or disagreed. Business owners that agreed they profited had an average investment of $188,500 in biomass production equipment, versus $377,143 for the neutral/disagree group (P = 0.02). Respondents indicated they were more likely to begin harvesting biomass to satisfy landowners and diversify operations rather than in response to encouragement from consuming facilities. Most owners viewed biomass harvesting positively and plan to continue production in the future.

Abstract

The average forest landowner in Wisconsin owns fewer than 30 acres, and in 2014, landowners with as few as 10 acres of forestland were eligible to enroll in a tax program that required periodic timber harvests. These factors point to a need for loggers capable of profitably harvesting small parcels of timber. A series of in-person interviews were conducted with representatives of 15 Wisconsin logging firms previously identified as successful at harvesting small parcels of timber. Ninety-two percent of mechanized loggers had harvested parcels of 10 acres and smaller within the past year. Eighty-five percent of mechanized loggers were willing to harvest parcels as small as 5 acres assuming that only a short move (<5 mi) was required between timber sales. The average direct moving cost for mechanized loggers was $406 per move, versus an estimated $778 when the costs of idle employees and equipment are included. Seventy-seven percent of the participants in this study purchased at least half of the timber that they harvested, and 85 percent performed services other than timber harvesting, such as establishing food plots, as a procurement tool. This study demonstrates that properly equipped Wisconsin loggers are profitably harvesting small parcels of timber; however, loggers and other timber buyers must recognize the additional costs associated with these harvests and adjust stumpage rates to compensate for these costs.

Abstract

Thermal modification can increase resistance to biological degradation, reduce equilibrium moisture content, and improve the dimensional stability of solid wood. In this study, oriented strand board (OSB) and two types of plywood were thermally modified as a posttreatment at 140°C, 150°C, 160°C, 170°C, and 180°C. Plywood moduli of rupture (MOR) and elasticity (MOE) decreased up to 54 and 22 percent, respectively, at the 180°C treatment, while OSB MOR and MOE decreased up to 25 and 4.3 percent, respectively. Internal bond strength of plywood decreased with increasing temperature, while OSB experienced minimal change. Screw-holding strength of all panels was more adversely affected by increasing temperatures than nail-holding strength, with OSB experiencing 17 and 27 percent maximum reductions in nail- and screw-holding strengths, respectively. Thickness swell performance of all panels improved with increasing temperature, with plywood exhibiting 41 and 77 percent improvements at the 160°C and 180°C treatments, respectively. Mass increase (when subjected to a water soak) of OSB decreased 12 percent at the 150°C treatment, after which it increased.

These results suggest that thermal modification posttreatments can improve the thickness swell and water absorption performance of plywood and OSB panels. However, some mechanical properties decreased significantly at treatment temperatures exceeding 160°C. The results provide a technical baseline that may help advance thermal modification technology from primarily solid-wood-only applications toward new, high-volume engineered wood markets. With further research, it may be possible to optimize the treatment technique(s) to ensure that the panels retain sufficient mechanical strength for the desired end-use applications.

Abstract

Transportation costs of ground forest residues can be reduced by increasing the dry wood bulk density per trailer per trip. Increasing the dry wood bulk density can be achieved by compacting the material into the trailer after it is processed by a grinder. However, increasing load density is often difficult to achieve in conventional conveyor-fed, gravity drop loading methods. The effect of high speed blowing during loading of low moisture wood grindings on the final bulk density was analyzed for two feedstock piece sizes, branches-and-tops and pulpwood. A structured fully randomized field test was implemented with two factors: loading method (high speed blowing and conveyor fed) and bit type (carbide hammer bits and knife-edge bits). The high speed blowing of grindings was made using a blower system to pack the material into the trailer during loading. The resulting bulk density using high speed blowing was compared against the results obtained from the conventional conveyor-fed (gravity drop) loading. The high speed blowing method produced a significant increase in bulk density ranging between 24 and 35 percent more than the conventional conveyor-fed loading. In terms of grinding configuration, knife-edge bits produced a higher bulk density (9%) compared with carbide hammer bits but only for the pulpwood piece size class. The use of high speed blowing during loading was the most powerful factor impacting truckload bulk density in these trials and demonstrated promising results that can lead to significantly lower transportation costs when processing low moisture content harvest residues.

Abstract

Routine inspection of wood utility poles to detect internal decay involves drilling holes at or about the ground line. While these holes are useful for detecting internal decay, their presence raises concern among engineers about their potential effects on pole flexural properties. The effect of inspection holes on flexural properties was studied on 92 Douglas-fir poles. Drilling up to six 20-mm-diameter inspection holes had no significant effect on flexural properties, indicating that inspection does not adversely affect pole condition.

Abstract

Detection and delimitation, usually accomplished via visual inspection, are primary tactics used for integrated pest management of drywood termite infestations, helping to determine whether whole-structure or localized treatment will be required. Borescopes, fiber-optic devices enabling views within voids, represent alternative or supplemental inspection tools, potentially increasing accuracy and efficiency. We observed and recorded successes of seven participants, with varied levels of termite inspection experience, when asked to identify sample items evidential of drywood termite infestation or likely to be confused with such items. Identifications were made in the laboratory, where samples were protected from view by a physical division, and in a simulated field environment, where samples were placed within inaccessible wall voids, some of which contained insulation material and were therefore designated as “external” voids. Identification accuracy was 80.6 percent overall, highest in the laboratory and lowest in external voids in the field. Differences due to participant became evident in the field, where accuracy ranged from 35.7 to 78.6 percent. Differences in identification accuracy due to sample type were important in both the laboratory and the field. In some cases, participants were able to achieve levels of identification accuracy comparable to those previously observed with alternative inspection devices such as acoustic emission and microwave. Borescope-aided inspection may be useful (but should not be solely relied upon) in cases where structural/environmental impediments are few, inspectors are experienced and physically able, and infestations are large enough to produce evidential items such as dead alate termites and accumulations of termite pellets.