The objective of this report is to summarize the scientific findings that support the environmental and economic benefits of using wood and wood products in green building construction. Despite documented advantages in many peer-reviewed scientific articles, most building professionals and members of the public do not recognize wood as a renewable resource or the role that efficient wood utilization plays in mitigating climate change and promoting healthy forests. Research and development of wood products and building systems also are lagging behind that of other materials. Both scientific advancement in the areas of life cycle analysis and development of new technologies for improved and extended wood utilization are needed to continue to advance wood as a green construction material. We provide three research and technology transfer recommendations that will allow USDA to help to achieve its climate change objectives while creating jobs, bolstering the competitive position and long-term economic stability of the industry, and reducing U.S. dependence on foreign oil.

This paper summarizes the results of an update to a resource assessment, published in 2005, commonly referred to as the Billion-Ton Study (BTS). The updated results are consistent with the 2005 BTS in terms of overall magnitude. The 2005 BTS projected between 860 and 1240 Tg of biomass available in the 2050 timeframe, while the Billion-Ton Update (BT2), for a price of 66 $ Mg-1, projected between 994 and 1483 Tg in 2030. For the BT2, forest residue biomass potential was determined to be less owing to tighter restrictions on forest residue supply including restrictions due to limited projected increase in traditional harvest for pulpwood and sawlogs. Crop residue potential was also determined to be less because of the consideration of soil carbon and not allowing residue removal from conventionally tilled corn acres. Energy crop potential was estimated to be much greater largely because of land availability and modeling of competition among various competing uses of the land. Generally, the scenario assumptions in the updated assessment are much more plausible to show a "billionton" resource, which would be sufficient to displace 30% or more of the country's present petroleum consumption and provide more than enough biomass to meet the 2022 requirements of the Renewable Fuel Standard. (C) 2014 Elsevier Ltd. All rights reserved.

Substantial knowledge has been generated in the U.S. about the resource base for forest-and other residue-derived biomass for bioenergy including co-firing in power plants. However, a lack of understanding regarding power plant-level operations and manager perceptions of drivers of biomass co-firing remains. This study gathered information from U.S. power plant managers to identify drivers behind co-firing, determine key conditions influencing past and current use, and explore future prospects for biomass in co-firing. Most of the biomass used in co-firing was woody biomass procured within 100 km of a power plant. Results show that the most influential co-firing drivers included: adequate biomass supply, competitive cost of biomass compared to fossil fuels, and costs of biomass transport. Environmental regulations were generally considered second-most influential in decisions to test or co-fire with biomass, but were of high importance to managers of plants that are currently not co-firing but may in the future. (C) 2013 Elsevier Ltd. All rights reserved.

Past studies have established measures of co-firing potential at varying spatial scales to assess opportunities for renewable energy generation from woody biomass. This study estimated physical availability, within ecological and public policy constraints, and associated harvesting and delivery costs of woody biomass for co-firing in selected power plants of the Northern U.S. Procurement regimes were assessed for direct sources of woody biomass from timberland including logging residues (slash, by-products), small-diameter trees, and integrated harvest (logging residues and small-diameter trees). Concentric woody biomass procurement areas were estimated for each power plant using county-level estimates and varying procurement radii. Delivered fuel cost estimates were calculated for each power plant and procurement regime based on incremental maximum transport distances. Procurement regimes focused on small-diameter trees can potentially produce the most electric power, but are constrained by lower economical transport distances than logging residues. These estimates enabled us to assess which power plants in the Northern U.S. had the highest electricity generation potential. For most procurement regimes, an average power plant co-firing had the potential to replace greater than 30% of coal electricity generation if there was no competition for the feedstock. However, woody biomass resource competition from adjacent co-firing plants could reduce this generation potential to less than 10%.

Consequential life cycle assessment (CLCA) has emerged as a tool for estimating environmental impacts of changes in product systems that go beyond physical relationships accounted for in attributional LCA (ALCA). This study builds on recent efforts to use more complex economic models for policy‐based CLCA. A partial market equilibrium (PME) model, called the U.S. Forest Products Module (USFPM), is combined with LCA to analyze an energy demand scenario in which wood use increases 400 million cubic meters in the United States for ethanol production. Several types of indirect economic and environmental impacts are identified and estimated using USFPM‐LCA. A key finding is that if wood use for biofuels increases to high levels and mill residue is used for biofuels and replaced by natural gas for heat and power in forest products mills, then the increased greenhouse gas emissions from natural gas could offset reductions obtained by substituting biofuels for gasoline. Such high levels of biofuel demand, however, appear to have relatively low environmental impacts across related forest product sectors.

Nationwide, county-level supply curves have been estimated for forest-based biomass to evaluate their potential contributions to producing biofuels. This study builds on the estimates of potential supply in the Billion Ton Supply study prepared by the U.S. Department of Agriculture and the U.S. Department of Energy. Forest biomass sources include logging residue, thinnings, other removals, unused mill residue, urban wood waste, and conventionally sourced wood (pulpwood size material). To make the estimates, we assume that lower cost forest biomass will be supplied from integrated harvesting operations that also remove sawlogs and pulpwood. We also assume that such removals can be estimated at the county level in two ways: first, as a portion of recent estimates of logging residues; and second, by simulated thinning operations that use tops, branches, and small trees for biomass. Supply from thinning dense forest stands is assumed to occur over 30 yr. Harvest and stumpage costs are estimated for each of these methods. Final supply estimates for each county assume supply that is half-way between the two estimates. Forest and agricultural biomass supply estimates have been used to indicate that for a cost of $44 per oven dry ton (odt) at forest roadside or farm gate, we could produce produce 20-billion gal of advanced biofuels as called for under the 2007 Energy Independence and Security Act. Forests could provide about 40-million odt to produce 4-billion gal, and agricultural feedstocks could provide about 200-million odt and produce 16-billion gal of biofuel.

The different uses of wood result in a hierarchy of carbon and energy impacts that can be characterized by their efficiency in displacing carbon emissions and/or in displacing fossil energy imports, both being current national objectives. When waste wood is used for biofuels (forest or mill residuals and thinnings) fossil fuels and their emissions are reduced without significant land use changes. Short rotation woody crops can increase yields and management efficiencies by using currently underused land. Wood products and biofuels are coproducts of sustainable forest management, along with the other values forests provide, such as clean air, water, and habitat. Producing multiple coproducts with different uses that result in different values complicates carbon mitigation accounting. It is important to understand how the life-cycle implications of managing our forests and using the wood coming from our forests impacts national energy and carbon emission objectives and other forest values. A series of articles published in this issue of the Forest Products Journal reports on the life-cycle implications of producing ethanol by gasification or fermentation and producing bio-oil by pyrolysis and feedstock collection from forest residuals, thinnings, and short rotation woody crops. These are evaluated and compared with other forest product uses. Background information is provided on existing life-cycle data and methods to evaluate prospective new processes and wood uses. Alternative management, processing, and collection methods are evaluated for their different efficiencies in contributing to national objectives.

The heightened interest in biofuels addresses the national objectives of reducing carbon emissions as well as reducing dependence on foreign fossil fuels. Using life-cycle analysis to evaluate alternative uses of wood including both products and fuels reveals a hierarchy of carbon and energy impacts characterized by their efficiency in reducing carbon emissions and/or in displacing fossil energy imports. Life-cycle comparisons are developed for biofuel feedstocks (mill and forest residuals, thinnings, and short rotation woody crops) with bioprocessing (pyrolysis, gasification, and fermentation) to produce liquid fuels and for using the feedstock for pellets and heat for drying solid wood products, all of which displace fossil fuels and fossil fuel-intensive products. Fossil carbon emissions from lignocellulosic biofuels are substantially lower than emissions from conventional gasoline. While using wood to displace fossil fuel-intensive materials (such as for steel floor joists) is much more effective in reducing carbon emissions than using biofuels to directly displace fossil fuels, displacing transportation fuels with ethanol provides the opportunity to also reduce dependence on imported energy. The complex nature of wood uses and how wood fuels and products interact in their environments, as well as the methods needed to understand these impacts and summarize the relative benefits of different alternatives, are discussed herein. Policies designed to increase biofuel use by subsidies or mandates may increase prices enough to divert biomass feedstock away from producing products, such as for composite panels, resulting in increased emissions from fossil fuel-intensive substitutes. Policies that fail to consider life-cycle implications are discussed, identifying their unintended consequences.

This review on research on life cycle carbon accounting examines the complexities in accounting for carbon emissions given the many different ways that wood is used. Recent objectives to increase the use of renewable fuels have raised policy questions, with respect to the sustainability of managing our forests as well as the impacts of how best to use wood from our forests. There has been general support for the benefits of sustainably managing forests for carbon mitigation as expressed by the Intergovernmental Panel on Climate Change in 2007. However, there are many integrated carbon pools involved, which have led to conflicting implications for best practices and policy. In particular, sustainable management of forests for products produces substantially different impacts than a focus on a single stand or on specific carbon pools with each contributing to different policy implications. In this article, we review many recent research findings on carbon impacts across all stages of processing from cradle-to-grave, based on life cycle accounting, which is necessary to understand the carbon interactions across many different carbon pools. The focus is on where findings are robust and where uncertainties may be large enough to question key assumptions that impact carbon in the forest and its many uses. Many opportunities for reducing carbon emissions are identified along with unintended consequences of proposed policies.

Business clusters are geographic concentrations of companies that provide mutual advantages for their participants. Clusters can include diverse members including competitors, customers, partners, and/or suppliers. In Alaska, wood products business clusters can have unique challenges associated with remote locations, high raw material costs, limited local markets, and potentially long transportation distances. Further, multiple land ownership near communities (for example state versus federal ownership) can influence raw material procurement, since different administrative processes for timber harvesting may be required. This study evaluates 2 resource dependent communities in southeast Alaska (Haines, AK and Craig, AK), seeking to identify elements that could enhance their potential for wood products clusters and new business formation. We consider how the flow of forest resources, from harvest to finished product, can influence local communities and either enhance or limit opportunities for wood products businesses. We evaluate the effect of various product mixes—including firewood, woody residues, house logs, lumber, and secondary wood products—on the composition, scale, and dynamics of wood products firms. We consider the effect of harvesting practices and proximity to timber sales in evaluating how land ownership can influence the viability of wood products clusters. Lastly we consider the impact of transportation costs on serving local and export markets. Our research builds upon past work in Alaska that evaluated national-forest based communities in Alaska, finding opportunities for greater innovation, higher productivity, and greater social well-being associated with wood products clusters.

In 2009, five unique methods were used to inspect vegetation-related conditions along Bonneville Power Administration (BPA) rights-of-way (ROW). Some methods were trials that BPA committed to execute as part of a settlement with its regional regulatory organization, the Western Electric Coordination Council (WECC), for violations of reliability standards from vegetation grow-in related outages. A combination of simple, stratified, and 100

The Lake States region of Minnesota, Wisconsin and Michigan offers significant potential for bioenergy production. We examine the sustainability of regional forest biomass use in the context of existing thermal heating, electricity, and biofuels production, projected resource needs over the next decade including existing forest product market demand, and impacts on price and feasibility. Assuming $36 per dry tonne at roadside, 4.1 million dry tonnes of forest biomass could be available region-wide. However, less is likely available due to localized environmental and forest cover type constraints, and landowner willingness to harvest timber. Total projected demand of 5.7 million dry tonnes, based on current and announced industry capacity, exceeds estimates of biomass availability, which suggests that anticipated growth in the forest-based bioeconomy may be constrained. Attaining projected demand will likely require a combination of higher cost feedstocks, integration of energy and non-energy uses, and careful management to meet environmental constraints. State distinctions in biomass harvest guidelines and the propensity for third-party forest certification will be critical in providing environmental safeguards. The cumulative effect of policy initiatives on biomass competition are discussed in the context of an emerging Lake States bioeconomy.