Karen L. Abt

Evaluation of silvicultural treatments and biomass use for reducing fire hazard in western states

Several analyses have shown that fire hazard is a concern for substantial areas of forestland, shrubland, grassland, and range in the western United States. In response, broadscale management strategies, such as the National Fire Plan, established actions to reduce the threat of undesirable fire. Available budgets are insufficient to pay for vegetative management on all acres where fire threat is considered unacceptable. The purpose of this report is to begin to identify locations in the west where fire hazard reduction treatments have a potential to “pay for themselves” at a scale and over a long enough time to make investment in additional forest product processing infrastructure a realistic option. The resulting revenues from these activities could presumably subsidize treatment for other locations. Accordingly, we concentrate on areas where wood removed during fire hazard reduction treatments has the potential to support a forest products infrastructure. Areas for treatment were selected by the criterion where either torching or crowning is likely during wildfires when wind speeds are below 25 mph. We considered thinning treatments designed to result in either evenaged or uneven-aged stand conditions. If there are ecological limitations on basal area that is allowed to be removed and there is a need to obtain a certain amount of merchantable wood volume to help cover costs, then uneven-aged treatments appear more likely to achieve one of our hazard reduction targets. Thinning to maintain an uneven-aged structure could be more controversial because it removes larger trees, although the revenue from such treatment covers harvest costs more frequently than does revenue from thinning to maintain an even-aged structure. The removal of large trees by uneven-aged thinning may be reduced by supplementary treatments to increase torching index rather than thinning to reach a high crowning index. Treatments analyzed would treat 7.2 to 18.0 million acres, including 0.8 to 1.2 million acres of wildland urban interface area, and would provide 169 to 640 million oven-dry tons of woody biomass (e.g., main stem, tops, and limbs). About 55% of biomass would be from sawlogs. Sixty to 70% of acres to be treated are in California, Idaho, and Montana. To prepare an example estimate of annual harvest amount for the 12 selected western states, we assume acres needing treatment are divided into two parts of equal area. For half the acres, an uneven-aged treatment would be applied if at least 300 ft3 of merchantable wood is removed; for the other half, an even-aged treatment would be applied if at least 300 ft3 of merchantable wood is removed. Under this scenario, treatment of 0.5 million acres/year would generate 14.6 million oven-dry tons of biomass per year or about 29% of the current level of roundwood removals for the selected states.

Economic optimisation of wildfire intervention activities.

We describe how two important tools of wildfire management, wildfire prevention education and prescribed fire for fuels management, can be coordinated to minimise the combination of management costs and expected societal losses resulting from wildland fire. We present a long-run model that accounts for the dynamics of wildfire, the effects of fuels management on wildfire ignition risk and area burned, and the effects of wildfire prevention education on the ignition risk of human-caused, unintentional wildfires. Based on wildfire management activities in Florida from 2002 to 2007, we find that although wildfire prevention education and prescribed fire have different effects on timing and types of fires, the optimal solution is to increase both interventions. Prescribed fire affects whole landscapes and therefore reduces losses from all wildfire types (including lightning), whereas wildfire prevention education reduces only human-caused ignitions. However, prescribed fire offers a longer-term solution with little short-term flexibility. Wildfire prevention education programs, by comparison, are more flexible, both in time and space, and can respond to unexpected outbreaks, but with limited mitigation longevity. Only when used together in a coordinated effort do we find the costs and losses from unintentional wildfires are minimised.

Potential Impact of Bioenergy Demand on the Sustainability of the Southern Forest Resource

The use of woody biomass for the production of domestic bioenergy to meet policy-driven demands could lead to significant changes in the forest resource. These impacts may be limited if woody biomass from forests is defined as only the residues from logging. Yet, if only residue is used, the contribution of woody biomass to a renewable energy portfolio will also be limited. As the definition of woody biomass is expanded, the impacts on the forest resource increase, as does the contribution of woody biomass to the renewable portfolio. A combination of markets and policies will determine the extent to which woody biomass can be used to meet renewable electricity requirements. This article develops two hypothetical demand scenarios based on the use of woody biomass in renewable electricity generation and uses these scenarios in a model of timber supply in the U.S. South to evaluate the effects on both timber markets and forest resource sustainability. The demands for woody biomass are met by a combination of residues from logging on private forests and increased harvest of pine pulpwood. We identify the dynamics of key characteristics of the southern forest resource, including forest type and age class distributions that vary under these demand scenarios.

Timber and Amenities on Nonindustrial Private Forest Land

Economic analyses of the joint production timber and amenities from nonindustrial private forest lands (NIPF) have been conducted for several decades. Binkley (1981) summarized this strand of research and elegantly articulated a microeconomic household model in which NIPF owners maximize utility by choosing optimal combinations of timber income and amenities. Most follow-up attempts have been limited to either simulations based on stylized characterization of joint production (Max and Lehman 1988) or to empirical representations hampered by data limitations— particularly with regard to measuring amenity production (Hyberg and Holthausen 1989). In attempting to redress this gap, Holmes (1986) was limited to binary representations of timber and amenities and did not get conclusive results. In this chapter, we use data from North Carolina that includes timber output and amenity indices to illustrate a method for empirically characterizing Binkley’s household model.

Carbon Mitigation Impacts of Increased Softwood Lumber and Structural Panel Use for Nonresidential Construction in the United States

Abstract More wood use in the United States to construct low-rise nonresidential (NR) buildings would increase consumption and production of softwood (SW) lumber, engineered wood products, and structural and nonstructural wood panels. Using a consequential life-cycle analysis, we estimated the change in net CO2 emissions that would be caused by increased use of SW lumber and structural panels in NR construction. Carbon (C) storage and emissions were projected over 50 years for baseline and increased wood use scenarios using the US Forest Products Module operating within the Global Forest Products Model (USFPM/GFPM) and the Southern region timber supply model (SRTS). Increased wood use in NR construction (C content of 428 million tons of carbon dioxide equivalent [tCO2e]) could provide an emissions reduction of 870 million tCO2e over 50 years or a net emissions reduction of 2.03 tCO2e/tCO2e of extra wood used in NR buildings over 50 years. The CO2 savings varied for products provided in the South, North, a...

Optimal timing of wildfire prevention education

Public outreach and wildfire education activities have been shown to limit the number of unintentional human-caused ignitions (i.e., ‘accidental’ wildfires). Such activities include the airing of public service announcements, visiting with homeowners in at-risk areas, distributing informative brochures and flyers, hosting of public forums (with presentations), and facilitating community sponsored neighborhood hazard assessments. By limiting the number of ignitions, prevention entirely avoids costs and losses related to fire suppression (initial attack) and property damage. In this paper, we show that the benefits of wildfire prevention education activities carried out in the State of Florida, USA, far outweigh their costs. We also report how the return on wildfire prevention education investment in that State varies—i.e., the effectiveness of these programs varies—with many exogenous factors, including weather, season, and recent wildfire history and fuels management activities. To illustrate how this effectiveness variation could be exploited to increase returns to money spent on prevention, we explore the optimal timing of wildfire prevention activities. Optimal timing of wildfire prevention education spending is defined as the spending allocation over time that yields the lowest wildfire-induced cost plus net value change to society. We find that, for Florida, the optimal (monthly) timing of prevention activities can be forecasted by exploiting the relationships between prevention effectiveness and fire weather measures, which vary predictably within the year.

Projecting housing starts and softwood lumber consumption in the United States

New residential construction is a primary user of wood products in the United States; therefore, wood products projections require understanding the determinants of housing starts. We model quarterly US total, single-family, and multifamily housing starts with several model specifications, using data from 1979 to 2008, and evaluate their fit out of sample, 2009 –14. Goodness-of-fit statistics show that parsimonious models outperform general models in out-of-sample predictions. Monte Carlo simulations of total housing starts to 2070 project median starts ranging from 0.86 million/year at 0% real gross domestic product (GDP) growth to 1.91 million/year at 5% real growth, with 90% uncertainty bounds ranging from 0.52 to 2.13 million/year. Assuming that future GDP growth equals the average rate observed over 1990 –2015, there is less than 9% probability that housing starts will exceed 2.0 million in any given year, 2016 –35. Results show no evidence of structural change in the determinants of total or single-family housing starts coincident with the recession of 2007– 09. Using these housing projections in a softwood lumber consumption model shows that GDP growth slower than 2% is consistent with stagnant or declining median softwood lumber consumption.

Optimal Stand Management

The traditional Faustmann (1849) model has served as the foundation of economic theory of the firm for the forestry production process. Since its introduction over 150 years ago, many variations of the Faustmann have been developed which relax certain assumptions of the traditional model, including constant prices, risk neutrality, zero production and management costs, and the single management objective. We describe the traditional Faustmann and provide an overview of the neotraditional Faustmann and Hartman (1976) models. We then use the neotraditional Hartman model to develop testable hypotheses regarding harvest response to timber, land, and amenity values from forests. Using data from the North Carolina coastal plain, we test for inclusion of several often omitted variables in models of industrial and nonindustrial harvest behavior.