The U.S. Forest Service Forest Products Laboratory (FPL), located in Madison, Wisconsin, celebrated its centennial in 2010, and one of the lab’s signature research areas during this century of achievement has been lignocellulosic transportation fuels. Many of these research advances have occurred either during wartime emergencies or times of economic crisis. Although great progress has been made, commercial production of lignocellulosic fuels has been limited. In this paper, the authors take an in depth look at advances, breakthroughs, and motivating factors in liquid fuels research both at the FPL and in the private sector. The authors examine the current status of lignocellulosic transportation fuels as well as near-term prospects for commercialization. The authors then summarize leading efforts at lignocellulosic fuel production in a comprehensive table. The authors consider the role that the FPL might have in developing lignocellulosic fuels during its second century as well as the commercial potential for private sector firms.
This report is a scientific assessment of the current condition and likely future condition of forest resources in the United States relative to climatic variability and change. It serves as the U.S. Forest Service forest sector technical report for the National Climate Assessment and includes descriptions of key regional issues and examples of a risk-based framework for assessing climate-change effects.
Many threats are jeopardizing the sagebrush steppe of the Columbia Basin, including the spread of invasive species such as cheatgrass (Bromus tectorum L.) and the expansion of western juniper (Juniperus occidentalis Hook.) into historic shrub steppe. Native sagebrush steppe provides productive grazing lands and important habitat for many wildlife species, and managers are in need of landscapescale tools to assess shrub steppe conversion risk and management options to maintain native shrub steppe. We used a state-and-transition modeling approach to project changes in sagebrush steppe vegetation across the landscape of southeastern Oregon. Models were constructed using both empirical data, including empirically derived fire probabilities, and expert opinion for processes that are still poorly documented, such as livestock grazing effects. With unrestricted grazing and no restoration treatments, future invasion by exotic annual grasses in warm, dry sagebrush steppe and juniper expansion into cool, moist sagebrush steppe are likely to accelerate in the next 50 years under current climatic conditions. Invasions are also likely to be
Iosco jobless rate passes 20 percent” read the headline in the Oscoda Press, February 3, 2010 (Nelson 2010). Although never described as prosperous, in the past, Iosco and neighboring Alcona, Crawford, and Oscoda Counties had benefited from diverse economies, with jobs found in small manufacturing plants, timber harvesting, wood processing facilities, and four-season recreation. But the economic downturn has been felt even in the relatively isolated communities of the Huron National Forest. When the opportunity arose to propose projects for Forest Service Recovery Act funding, staff on the Mio and Huron Shores Ranger Districts asked how they could develop a safe Total Forest Service Recovery Act Investment in Michigan (as of 09/08/09): ~$39,382,290 (Michigan projects: $34,557,000; Michigan share of multistate projects: ~$4,825,290)
Many factors increase susceptibility of forests to wildfire. Among them are increases in human population, changes in land use, fire suppression, and frequent droughts. These and other factors have been exacerbating forest susceptibility to wildfires over the past century in southern California. We report on the significant role that air pollution has had on increasing forest susceptibility to wildfires, based on a 1999-2003 case study in the San Bernardino Mountains. Air pollution, specifically ozone (O-3) and wet and dry deposition of nitrogenous (N) compounds as a by-product of fossil fuel combustion, has significantly increased since urbanization and industrialization of the region after 1945. Ozone and elevated N deposition cause specific changes in forest tree carbon (C), N, and water balance that enhance individual tree susceptibility to drought, bark beetle attack, and disease, and when combined, contribute to whole ecosystem susceptibility to wildfire. For example, elevated O-3 and N deposition increase leaf turnover rates, leaf and branch litter, and decrease decomposability of litter, creating excessively deep litter layers in mixed-conifer forests affected by air pollutants. Elevated O-3 and N deposition decrease the proportion of whole tree biomass in foliage and roots, thereby increasing tree susceptibility to drought and beetle attack. Because both foliar and root mass are compromised, carbohydrates are stored in the bole over winter. Elevated O-3 increases drought stress by significantly reducing plant control of water loss. The resulting increase in canopy transpiration, combined with O-3 and N deposition-induced decreases in root mass, significantly increases tree susceptibility to drought stress, likely contributing to successful host colonization and population increases of bark beetles. Phenomenological and experimental evidence is presented to support the role of these factors contributing to an increase in the susceptibility of forests to wildfire in southern California.
Swiss needle cast of Douglas-fir (Pseudotsuga menziesii) is Caused by the ascomycete Phaeocryptopus gaeumannii. Symptoms are foliage chlorosis and premature needle abscission due to occlusion of stomata by the ascocarps of the pathogen, resulting in impaired needle gas exchange. Growth losses of 20%-50% due to Swiss needle cast have been reported for approximately 150 000 ha of Douglas-fir plantations in western Ore oil since 1996. In the western Coast Range of Oreuon and in New Zealand, winter temperature is strongly correlated with pathogen abundance. Models for predicting, disease severity based oil winter temperature account for 77% and 78% of the variation in 1- and 2-year-old needles, respectively, for western Oregon sites and approximately 80% for New Zealand. A trend of temperatures increasing by 0.2-0.4 degrees C during the Winter Months and Spring precipitation increasing by 0.7-1.5 cm/decade since 1970 suggests that regional climate trends are influencing the current distribution and severity of Swiss needle cast disease. Continuing winter temperature increases predicted for the Pacific Northwest of approximately 0.4 degrees C/decade through 2050 suggest that the severity and distribution of Swiss needle cast is likely to increase in the coming decades as a result of climate change. with significant consequences for Pacific Northwest forests.
The southern pine beetle, Dendroctonus frontalis (Zimmerman) (Coleoptera: Curculionidae: Scolytinae) (SPB), is an indigenous invasive species that infests and causes mortality to pines (Pinus spp.) throughout the Southern United States. The hemlock woolly adelgid, Adelges tsugae (Annand) (Homoptera: Adelgidae) (HWA), is a nonindigenous invasive species that infests and causes mortality to Eastern hemlock (Tsuga canadensis (L.) Carr.) and Carolina hemlock (T. caroliniana Engelm.) throughout their range in Eastern North America. Both of these insect species occur in the Southern Appalachians, and both have recently caused tree mortality exceeding historical records. Herbivory by both species is of concern to forest managers, but for different reasons. In the case of the SPB, emphasis centers on forest restoration strategies, and in the case of the HWA, the concern is on predicting the impact of removing hemlock from the forest environment. Both of these issues can be investigated using a landscape simulation modeling approach. LANDIS is a simulation modeling environment developed to predict forest landscape change over time. It is a spatially explicit, landscape-scale ecological simulation model that incorporates disturbance by fire, wind, biological disturbance (insects and pathogens) and harvesting. Herein, we present a case study using LANDIS to evaluate the impact of herbivory by the SPB and HWA on forest landscapes in the Southern Appalachians.
Government agencies, industrial landowners, and private landowners often strive to maintain soil quality after site management activities in order to maintain site productivity, hydrologic function, and ecosystem health. Soil disturbance resulting from timber harvesting, prescribed fire, or site preparation activities can cause declines, improvements, or have no effect on site productivity and hydrologic function. In many cases, detailed soil resource data can be used to determine the stress level and ecosystem health of stands and may be one method used to determine the risk of disease or insect outbreak. Currently, organic matter accumulations in many forests exceed historical levels. Fire suppression or fire exclusion has produced numerous overstocked stands. When this condition is combined with increased climatic variation, drought, and type conversion, these stands have a high risk for catastrophic wildfire. The resulting large, high-intensity, and high-severity fires could contribute to changes in soil quality and lead to outbreaks of insects and diseases in many ecosystems. Changes in ecosystem processes can also be associated with changes in overstory properties that alter forest stand resilience. For example, loss of western white pine to blister rust infection in the Northwestern United States has caused a type conversion to forest species that are not tolerant of root diseases, are not fire resistant, and sequester nutrients in the surface mineral soil and tree crown that can later be lost through logging or fire. These relationships, and others, can be used in conjunction with soil resource data bases to assess susceptibility to threats and to help develop management strategies to mitigate disturbances. Development of monitoring strategies that use common methods that can be utilized by a variety of land management agencies and specialists is a key component for relating forest health to soil changes after fire or other land management activities.
We used state and transition models to integrate natural disturbances and management activities for a 275 000-ha landscape in the central Oregon Cascades. The landscape consists of a diverse mix of land ownerships, land use allocations, and environments. Three different management scenarios were developed from public input: (1) no management except wildfire suppression on federally managed lands, (2) manage Federal lands to increase multistory forests of large and very large trees, and (3) manage Federal lands to move toward historical conditions. All scenarios treated privately owned lands as if they were wildlandurban interface (WUI) areas and all recognized wilderness, reserves, and general forests within federally managed lands. Models were run for 200 years and 30 Monte Carlo simulations to include variability in fire years and other natural disturbances. Passive management on federally managed lands resulted in small increases in single-story and multistory large-tree forests and increases in highseverity wildfire and insect outbreaks. Managing toward multistory large- and very-large-tree forests resulted in minor increases in those forest types and increased wildfire and insect outbreaks. Contrary to intent, this scenario did not generate appreciable increases in multistory large- and very-large-tree forests. Managing toward historical conditions resulted in strong increases in single-story large- and very-large-tree forests and decreases in high-severity wildfire and insect outbreaks. All three scenarios resulted in conversion of most WUI to open grass, shrub, and forest conditions.
The construction of the 2006 National Insect and Disease Risk Map, compiled by the USDA Forest Service, State and Private Forestry Area, Forest Health Protection Unit, resulted in the development of a GIS-based, multicriteria approach for insect and disease risk mapping that can account for regional variations in forest health concerns and threats. This risk mapping framework, used by all nine Forest Service regions and 49 States, provides a consistent, repeatable, transparent process through which interactive spatial and temporal risk assessments can be conducted at various levels to aid in decisionmaking. The national framework was designed to be highly iterative, using input from a wide range of sources including subject area experts. The framework consists of a five-step process: (1) identify agents of concern (insects and diseases) and target-host species; (2) identify, rank, and weight criteria that determine the susceptibility (potential for introduction and establishment) and vulnerability (potential for tree mortality to occur if an agent is established) to each agent; (3) standardize criteria values, and combine the resultant maps using a series of weighted overlays; (4) convert modeled values for each agent to predicted basal area (BA) loss over a 15-year period; and (5) identify regions at risk of encountering a 25-percent or greater loss of total basal area in the next 15 years. This potentially interactive threshold was set by the National Risk Map Oversight team for the national risk map product. The National Insect and Disease Risk Map resulted in the integration into a national map of 186 forest insect and disease models, individually run and assembled on a central server located at the Forest Health Technology Enterprise Team (FHTET) in Fort Collins, Colorado. The national framework also enables local knowledge and data to be entered into models, allowing for quick, large-scale assessments. The development of this national framework is described here.
Numerous factors, some of which cannot be controlled, are continually interacting with the forest resource, introducing risk to management, and making consistent predictable management outcomes uncertain. Included in these factors are threats or hazards such as windstorms and wildfire. Factors influencing the probability (risk) of windthrow or windsnap occurring can be grouped into four broad categories: regional climate, topographic exposure, soil properties, and stand characteristics. Of these categories, stand characteristics are most commonly and easily modified through forest management. To augment our understanding of the interaction between forest management and wind damage vulnerability in Maine, we developed a wind damage model that reflects site and stand characteristics. Model calibration used information from published literature and experiences of regional managers. The model was evaluated using spatially explicit wind damage records from a 40 800-ha managed forest area in northern Maine. A comparison of means analysis identified significant differences in vulnerability index values between categorical populations of stands that have either recorded blowdown or no recorded blowdown during the last 15 years.
A framework that organizes natural and protected areas is often used to help understand the potential risks to natural areas and aspects of their ecological and human dimensions. The spatial (or landscape) context of these dynamics is also a critical, but, rarely considered, factor. Common classification systems include the U.S. Geological (USGS) Gap Analysis Program GAP) stewardship coding scheme, the International Union for the Conservation of Nature (IUCN) Protected Area Management Categories, and the American Planning Association (APA) Land-Based Classification Standards. The GAP and IUCN frameworks are coarse classifications (four to eight categories), whereas the APA focuses primarily on private land uses. To address these limitations, we develop here more refined implementation methods based on the human modification framework, which conceptually is rooted in characterizing the degree to which natural processes are free or controlled, and the degree to which landscape patterns are natural or artificial. To provide useful and tighter coupling of specific threats and spatial data surrogates, we refine the conceptual basis by identifying three primary types of human activities that cause modification of natural systems and patterns. These are land uses categorized as urban/built-up, recreation, and production/extraction. We detail specific metrics and common data used as surrogates that can provide a stronger basis for characterizing the degree of human modification. We illustrate our methods by presenting analysis results for a Colorado case study.
Current information on broad-scale climatic conditions is essential for assessing potential distribution of forest pests. At present, sophisticated spatial interpolation approaches such as the Parameter-elevation Regressions on Independent Slopes Model (PRISM) are used to create high-resolution climatic data sets. Unfortunately, these data sets are based on 30-year normals and rarely incorporate up-to-date data. Furthermore, because they are constructed on a monthly rather than a daily time step, they do not directly measure simultaneous occurrence of multiple climatic conditions (e.g., days in the past year with appropriate temperature and adequate precipitation). Yet, the actual number of days—especially consecutive days—where multiple conditions are met could be significant for pest dispersal or establishment. For the sudden oak death pathogen (Phytophthora ramorum), we used National Oceanic and Atmospheric Administration daily weather station data to create current, national-scale grids depicting co-occurrence of multiple climatic conditions. For each station, we constructed two count-based variables: the total number of days and the greatest number of consecutive days in a year where the station met several conditions (temperature, rain/fog, relative humidity). We then employed gradient plus inverse distance squared (GIDS) interpolation to generate grids (4-km2 resolution) of these variables for 5 years (2000-2004). The GIDS technique weights standard inverse distance squared interpolation using coefficients based on geographic location (x, y) and a spatial covariate such as elevation. Using these variables, we determined the GIDS coefficients for each output grid cell via Poisson regression on the 30 closest stations. We also performed model selection to ensure only significant variables contributed to the GIDS coefficients. We compared the GIDS approach to cokriging and detrended kriging using cross-validation and found similar accuracies among all three interpolation methods. We also compared the output grids to maps assembled from the PRISM data depicting the probability all conditions were met in a given year. As expected, we found differences in areas highlighted as suitable for P. ramorum establishment by the two methods. We suggest that using current weather data and calculating the variable of interest directly will provide more practical information for mapping forest pest risk.
