U.S. Department Of Agriculture Forest Service Research Articles

Forest Biomass Policies and Regulations in the United States of America

Using woody biomass from public lands could attract private investments, increase carbon dioxide emission reductions from sustainably harvested low-grade wood to mitigate climate change, provide benefits for the environment, and support rural community economies. Available for use are about 210 million oven dry tons (in the western U.S. alone) of small-diameter wood and harvest residues that could be removed through hazard-fuel treatments and used for bioenergy and bioproducts; representing an economic value of approximately USD 5.97 billion (109). Reaching that utilization goal requires an assessment of current U.S. policies, regulations and directives influencing the use of forest biomass and identification of barriers, challenges, and potential opportunities associated with the use of woody biomass from public lands. One objective of this review is to support the implementation of the U.S. Department of Agriculture, Forest Service (USDA-FS) new effort called “Confronting the Wildfire Crisis: A Strategy for Protecting Communities and Improving Resilience in America’s Forests”, but greater coordination of public policies (regulatory legislation, government subsidies, support programs) at different government levels could increase adoption of forest biomass for bioenergy and bioproducts while also promoting different supply chains for long-term biomass supplies and industry investments. Harmonizing the definition of key biomass terms used by different programs that support using forest biomass for bioenergy and other bioproducts, including the Renewable Fuel Standard, may increase forest biomass use from public lands.

Circular utilization of urban tree waste contributes to the mitigation of climate change and eutrophication

Circular utilization of urban tree waste contributes to the mitigation of climate change and eutrophication

Is This Flight Necessary? The Aviation Use Summary (AUS): A Framework for Strategic, Risk-Informed Aviation Decision Support

Across the globe, aircraft that apply water and suppressants during active wildfires play key roles in wildfire suppression, and these suppression resources can be highly effective. In the United States, US Department of Agriculture Forest Service (USFS) aircraft account for a substantial portion of firefighting expense and higher fatality rates compared to ground resources. Existing risk management practices that are fundamental to aviation safety (e.g., routinely asking, “Is this flight necessary?”) may not be appropriately scaled from a risk management perspective to ensure that the tactical use of aircraft is in clear alignment with a wildfire’s incident strategy and with broader agency and interagency fire management goals and objectives. To improve strategic risk management of aviation assets in wildfire suppression, we present a framework demonstrating a risk-informed strategic aviation decision support system, the Aviation Use Summary (AUS). This tool utilizes aircraft event tracking data, existing geospatial datasets, and emerging analytics to summarize incident-scale aircraft use and guide decision makers through a strategic risk management process. This information has the potential to enrich the decision space of the decision maker and supports programmatic transparency, enhanced learning, and a broader level of accountability.

Hardwood Log Grading in the United States—Part II: United States Forest Service Log Grades and the Hardwood Industry

AbstractThe major effort to develop hardwood log grades was undertaken by the US Department of Agriculture Forest Service (USDAFS) during the 1940s through the 1960s. While the USDAFS officially adopted the grading system for their own use in 1952, it has never taken hold in the hardwood lumber industry. This article discusses the variety of reasons that have most likely contributed to this failure of adoption of the USDAFS system by the industry, ranging from ease of use, to individual log grades covering wide ranges of log characteristics/quality, and to overlapping grades for a given set of log attributes, among others. Finally, the authors suggest developing a hardwood log grading system that embraces the de facto industry system of scaling diameter and clear faces.

Hardwood Log Grading in the United States—Part 1: A Historical Perspective

Abstract The ability to efficiently and consistently characterize the quality of hardwood sawlogs is an indispensable part of operating a hardwood sawmill. And it is equally important for buyers and sellers of hardwood logs to negotiate prices on a uniform basis of both scale and grade. While scaling of logs is relatively straightforward, assuming buyer and seller agree on a specific log rule to use (e.g., Doyle, Scriber, International), grading logs for the purposes of evaluating quality is more complex. Hardwood log grading is an essential component of any hardwood sawmill's operation and effectively sets the stage for profit or loss. Various efforts have been made to develop a standardized log grading system by both the forest products industry and the US Department of Agriculture Forest Service (USDAFS) since the beginning of the 20th century. However, even after over a century of effort, there is still no broadly accepted standard for grading hardwood logs. The purpose of this article is to document the historical evolution of hardwood log grading systems. Understanding the development of hardwood log grading systems over time can help to produce a better log grading standard in the future.

Conservation of Aquatic Biodiversity in the Context of Multiple‐Use Management on National Forest System Lands

The U.S. Department of Agriculture Forest Service (USFS) manages 193 million acres of public lands across 43 states and Puerto Rico. The original intent behind reserving lands managed by the USFS was to improve and protect forests, secure favorable conditions for water flows, and furnish a continuous supply of timber for the nation. Through time national forests have evolved, so they are managed for a broad array of uses. Differing expectations have led to conflicts between aquatic conservation and other aspects of the USFS’ mandate. In the 1990s, these conflicting goals came to a head with the listing of the northern spotted owl Strix occidentalis caurina and the need to better protect streams that fostered populations of anadromous salmonids. To better balance these conflicting uses, the agency placed additional emphasis on conserving and restoring aquatic systems by integrating conservation concepts into the forest planning process. If the USFS is to succeed in protecting and restoring aquatic biodiversity, it must continue to address traditional challenges such as minimizing the effects of timber harvest, roads, grazing, and mining on aquatic systems while improving policies and practices regarding contemporary challenges such as climate change and invasive species.

Quality Indexes for Oak Sawlogs Based on Green Lumber Grade Yields

Abstract Quality Indexes for red oak (Quercus rubra) and white oak (Quercus alba) logs were established using multivariate regression models developed by the US Department of Agriculture (USDA) Forest Service that predicted green 4/4 lumber grade yields from hardwood sawlogs. Past Quality Indexes were based on air-dried lumber grade yields, but these yields can be affected by mill-specific factors. Considering green lumber as the finished product isolated the drying process and any subsequent changes in lumber product value from the analysis. Lumber grades were consistent with National Hardwood Lumber Association specifications, while log grades were based on the USDA Forest Service grading rules. Input data into the models included log scaling diameter, log length, and percent scaling defect. Green lumber grade yields were then used along with price relatives developed from 5-year lumber grade price averages (nominal) to develop Quality Indexes for each species. Two applications of the Quality Index are ...

Changes in Snag Populations on National Forest System Lands in Arizona, 1990s to 2000s

Snags receive special management attention as important components of forest systems. We used data from the US Department of Agriculture (USDA) Forest Service Forest Inventory and Analysis Program, collected during two recent time periods (1995 to 1999 and 2001 to 2010), to evaluate trends in snag populations in two forest types in Arizona. Densities of snags ≥4 in. dbh increased by 21 and 72% between these time periods in mixed-conifer and ponderosa pine (Pinus ponderosa) forest, respectively. Proportions of plots meeting USDA Forest Service guidelines for density of large snags (defined as snags ≥18 in. dbh and ≥30 ft tall) increased between time periods in both forest types (from 19 to 45% in mixed-conifer and from 5 to 17% in ponderosa pine forest), but large snags remained relatively sparse, especially in less productive ponderosa pine forests. More than 50 and 75% of sampled plots lacked large snags entirely in mixed-conifer and ponderosa pine forest, respectively.

An Aquatic Organism Passage Story Map

As the manager of 380,000 miles of roads and tens of thousands of road-stream crossings, the U.S. Department of Agriculture Forest Service (USFS) plays a critical role in aquatic connectivity. Surv...

Density of Large Snags and Logs in Northern Arizona Mixed-Conifer and Ponderosa Pine Forests

Large snags and logs provide important biological legacies and resources for native wildlife, yet data on populations of large snags and logs and factors influencing those populations are sparse. We monitored populations of large snags and logs in mixed-conifer and ponderosa pine (Pinus ponderosa) forests in northern Arizona from 1997 through 2012. We modeled density of large snags and logs as a function of forest type, time period, and environmental characteristics of sampled plots. Our objective was to build models that best explained current densities of these structures using these available covariates. The best model for density of large snags indicated that snag density was greater in mixed-conifer than in ponderosa pine forests, lower in plots with evidence of past timber or fuelwood harvest than in plots lacking such evidence, and covaried positively with mean slope and distance to road. The best model for density of large logs indicated that log density was greater in mixed-conifer than in ponderosa pine forests and covaried positively with solar insolation and surface ratio (an index of topographic roughness). The best snag model predicted that current US Department of Agriculture (USDA) Forest Service guidelines for retention of large snags were met only in mixed-conifer forests lacking evidence of past harvest activity. In contrast, the USDA Forest Service guidelines for retention of large logs were met in both forest types. Our results suggest that ease of human access and management history influence density of large snags, that current snag guidelines are unlikely to be met without considering these impacts, and that those guidelines may not be readily attainable in much of the landscape.

Where Occupation and Environment Overlap: US Forest Service Worker Exposure to Libby Amphibole Fibers

The National Institute for Occupational Safety and Health (NIOSH) conducted an evaluation of exposures to asbestiform amphibole, known as Libby Amphibole (LA), to personnel from the US Department of Agriculture-Forest Service (USFS) working in the Kootenai National Forest near a former vermiculite mine close to Libby, Montana. LA is associated with vermiculite that was obtained from this mine; mining and processing over many years have resulted in the spread of LA into the surrounding Kootenai Forest where it has been found in tree bark, soil, and forest floor litter. As a result of this and other contamination, Libby and surrounding areas have been designated a “Superfund” site by the US Environmental Protection Agency (EPA). This article describes the application of EPA methods for assessing cancer risks to NIOSH sampling results. Phase-contrast microscopy for airborne asbestos fiber evaluation was found to be less useful than transmission electron microscopy in the presence of interfering organic (plant) fibers. NIOSH Method 7402 was extended by examination of larger areas of the filter, but fiber counts remained low. There are differences between counting rules in NIOSH 7402 and the ISO method used by EPA but these are minor in the context of the uncertainty in concentration estimates from the low counts. Estimates for cancer risk are generally compatible with those previously estimated by the EPA. However, there are limitations to extrapolating these findings of low risk throughout the entire area and to tasks that were not evaluated.

Progress in Private Forest Landowner Estimation

T wo recent issues of the Journal of Forestry contained a discussion of methods for estimating private forest landowner (PFL) population parameters. Initially, Metcalf et al. (2012) raised questions about the application of unequal probability estimation equations to samples of PFLs drawn proportional to property size (i.e., PPS). In response, Dickinson and Butler (2013) presented corrections to National Woodland Owner Survey (NWOS) methods that clarified sampling protocols and revised equations and procedures used to generate estimates of PFL parameters. Dickinson and Butler (2013) also raised questions about the validity of the analysis and conclusions reached by Metcalf et al. (2012). This response addresses those questions, amends conclusions presented in Metcalf et al. (2012), and expands the discussion of implications for managers and researchers concerned with private forest ownership and management. It was never our intent to critique and/or debate methodological issues. Our research was funded by the Pennsylvania Department of Conservation and Natural Resources, Bureau of Forestry with the specific goal of informing outreach and extension efforts promoting stewardship of the Commonwealth’s vast private forest (approximately 11.5 million acres, 70% of the state’s forestland). This project did not focus on the exploration of the functionality of estimation equations. Our methodological approach was fashioned after the NWOS methods presented in US Department of Agriculture (USDA) Forest Service publications (e.g., Birch 1996, Butler et al. 2005), but coupled to a substantial increase in sampling intensity. After collecting data and conducting different analyses, we were left with curiously incongruent results (e.g., estimates of PFL population size in the millions rather than the hundreds of thousands reported in the NWOS). This finding led us to initiate a systematic review of both the NWOS methods and our own to explore possible sources for bias and/or error. The review uncovered problems with the NWOS estimation equations and their application. We presented these findings in Metcalf et al. (2012), in which we specifically addressed the confusion of inclusion probabilities with selection probabilities and the erroneous exclusion of duplicate PFL selections when using the Hansen-Horvitz estimator (HHE). The implications of these errors on our data and the resources needed to conduct the review itself severely constrained our research. The conclusions tied to estimation approaches helped clarify our research, led to changes in NWOS estimation procedures as presented by Dickinson and Butler (2013), and allowed other researchers to have significantly more confidence when designing and interpreting results from PFL studies. Dickinson and Butler (2013) dismissed the issues presented in Metcalf et al. (2012) as trivial because of an unestablished theoretical basis (p. 319), case study methodology (p. 320), limited sampling intensity of NWOS (p. 323), and unaddressed issues (i.e., nonprivate forest sampling points and variance estimation, p. 323, 324). We disagree. Consumers of NWOS results need to be assured that they are unbiased; researchers using USDA Forest Service methods also need to be assured that their resulting estimates are unbiased. This was not the case before the publication of Metcalf et al. (2102). Indeed, Dickinson and Butler (2013) acknowledged the following two errors in past NWOS methods: confusion of selection probability and inclusion probability calculations; and unwarranted omission of duplicate selections of PFLs in the sampling process. Such errors, when applied to sampling designs identical to NWOS, produce biased estimates (increasingly so as sample size increases), thus potentially affecting past NWOS panels and any PFL study replicating NWOS methods before this discussion. Further, because the source of bias is largely affected by the exclusion of duplicate selections of PFLs, estimates for areas of interest (e.g., regions and states) characterized by larger private forest parcels (i.e., the western United States) may be disproportionately biased. Dickinson and Butler (2013) suggested a review of past NWOS data to explore possible changes in results due to updated methods; we strongly encourage this analysis of legacy NWOS data because it will help us understand the full implication of these errors on past results and reveal true trends in private forest ownership characteristics. Allocations of federal formula funds are, in part, determined by estimates of PFL population sizes by state and/or region. Parcelization patterns vary disproportionately across states: some states are highly parcelized, whereas others are less so. Thus, the likelihood for duplicate selections of PFLs in past NWOS sampling varies from state to state. It follows that the bias in estimates of PFL population parameters (including total population size) may be more pronounced in some states than others; this bias results in skewed resource allocations. Understanding the nature of such errors would not be possible without analysis of past NWOS data using revised methods. This type of legacy analysis to remove past bias is essential for a longitu-

Narrative History of the Resistance Screening Center: It’s Origins, Leadership and Partial List of Public Benefits and Scientific Contributions

Forty years ago, the US Department of Agriculture (USDA) Forest Service developed and currently operates the Resistance Screening Center near Asheville, North Carolina, as a service to both industry and university-based tree improvement programs and tree-seed exporting companies in the southern US, Mexico, and Central America. Seed lots from more than 15,000 selections of slash and loblolly pines have been evaluated for genetically-controlled resistance to fusiform rust and other diseases including pitch canker, dogwood anthracnose, and brown spot needle blight. The screening system uses a greenhouse-based artificial inoculation system with controlled density of inoculum from geographically diverse sources of the rust pathogen. Results are completed in 6–9 months and are reasonably well-correlated with field-based progeny tests. Operating costs of the Center are shared by both the USDA Forest Service and its clients. The technologically sophisticated methods and professional skills of the Center staff have been applied to facilitate and accelerate progress in region-wide timber production, scientific understanding of the fusiform rust pathosystem, and graduate education of forest geneticists and pathologists in universities.

USDA Forest Service research and development - caring for the land and serving people

Total forested area in North America is 677.5 million ha (32.7% of land area), which is 17.1% of the global forests. Total area of the U.S forests is 303 million ha, which is the 4th largest in the World behind the Russian Federation, Brazil and Canada. In 1876, the United States Congress created the office of Special Agent in the Department of Agriculture to assess the quality and conditions of forests in the United States. In 1881, the office was expanded into the Division of Forestry. The Forest Reserve Act of 1891 authorized withdrawing land from the public domain as “forest reserves” managed by the Department of the Interior. In 1901, the Division of Forestry was renamed the Bureau of Forestry. The Transfer Act of 1905 transferred the management of forest reserves from the General Land Office of the Interior Department to the Bureau of Forestry, henceforth known as the US Forest Service (http://www.fs.fed.us/aboutus/history/). Presently the agency is part of the US Department of Agriculture (USDA). The USDA Forest Service (USDA FS) manages public lands, provides assistance in management of the privately-owned forested lands, and does research. Major divisions of the agency include the National Forest System, State and Private Forestry, and the Research and Development (R&D) branches. The R&D branch provides research support for forests and range management and helps in knowledge and technology transfer to the National Forest System and the State and Private Forestry. The United States currently has a system of 155 national forests, 20 national grasslands, and 79 research and experimental forests, as well as other special areas, covering more than 193 million acres of public land (Adams et al. 2008). The USDA FS has evolved into a 30,000 employee agency that manages the national forests for a number of multiple uses, including recreation, timber, wilderness, minerals, water, grazing, fish, and wildlife (http://www.fs.fed.us/aboutus/history/). As of fiscal year 2010, the USDA FS has a total budget authority of $5.15 billion, of which 42% is spent fighting fires (http://www.fs.fed.us/aboutus/budget/). The mission of the USDA FS is: to sustain the health, diversity, and productivity of the Nation’s forests and grasslands to meet the needs of present and future generations. Its motto is: caring for the land and serving people. As a lead Federal Agency in natural resource conservation, the USDA FS provides leadership in the protection, management, and use of the Nation’s forest, rangeland, and aquatic ecosystems.

Carbon stocks on forestland of the United States, with emphasis on USDA Forest Service ownership

The U.S. Department of Agriculture Forest Service (USFS) manages one-fifth of the area of forestland in the United States. The Forest Service Roadmap for responding to climate change identified assessing and managing carbon stocks and change as a major element of its plan. This study presents methods and results of estimating current forest carbon stocks and change in the United States for public and private owners, consistent with the official 2010 U.S. greenhouse gas inventory, but with improved data sources for three states. Results are presented by National Forest System region, a major organizational management unit within the Forest Service, and by individual national forest. USFS forestland in the United States is estimated to contain an average of 192 Mg C/ha (megagrams carbon per hectare) on 60.4 million ha, for a total of 11,604 Tg C (teragrams C) in the year 2005. Privately-owned forestland averages 150 Mg C/ha on 173.8 million ha, with forestland of other public owners averaging 169 Mg C/ha on 43.1 million ha. In terms of change, private and USFS ownerships each sequester about a net 150 Tg CO2/yr, but an additional 92 Tg CO2/yr is stored in products from private harvests compared to about 3 Tg CO2/yr from harvest on USFS land. Emissions from other disturbances such as fires, as well as corresponding area estimates of disturbance are also important, but the needed datasets are not yet available. Recommendations are given for improving the estimates.

Urban Forest Health Monitoring: Large-Scale Assessments in the United States

The U.S. Department of Agriculture, Forest Service (USFS), together with state partners, developed methods to monitor urban forest structure, function, and health at a large statewide scale. Pilot studies have been established in five states using protocols based on USFS Forest Inventory and Analysis and Forest Health Monitoring program data collection standards. Variables and data analysis are described. Advantages of a large-scale monitoring study are discussed and examples of results from Wisconsin are presented. Studies in Indiana, Wisconsin, New Jersey, Tennessee, and Colorado, U.S., have shown that urban forest health monitoring data collection and analysis is feasible and can be implemented nationally.

Conterminous U.S. and Alaska Forest Type Mapping Using Forest Inventory and Analysis Data

Classification-trees were used to model forest type groups and forest types for the conterminous United States and Alaska. The predictor data were a geospatial data set with a spatial resolution of 250 m developed by the U.S. Department of Agriculture Forest Service (USFS). The response data were plot data from the USFS Forest Inventory and Analysis program. Overall accuracies for the conterminous U.S. for the forest type group and forest type were 69 percent (Kappa � 0.66) and 50 percent (Kappa � 0.57), respectively. The overall accuracies for Alaska for the forest type group and forest type were 78 percent (Kappa � 0.69) and 67 percent (Kappa � 0.61), respectively. This is the first forest type map produced for the U.S. The forest type group map is an update of a previous forest type group map created by Zhu and Evans (1994).

A Project for Monitoring Trends in Burn Severity

Elected officials and leaders of environmental agencies need information about the effects of large wildfires in order to set policy and make management decisions. Recently, the Wildland Fire Leadership Council (WFLC), which implements and coordinates the National Fire Plan (NFP) and Federal Wildland Fire Management Policies (National Fire Plan 2004), adopted a strategy to monitor the effectiveness of the National Fire Plan and the Healthy Forests Restoration Act (HFRA). One component of this strategy is to assess the environmental impacts of large wildland fires and identify the trends of burn severity on all lands across the United States. To that end, WFLC has sponsored a six-year project, Monitoring Trends in Burn Severity (MTBS), which requires the U.S. Department of Agriculture Forest Service (USDA-FS) and the U.S. Geological Survey (USGS) to map and assess the burn severity for all large current and historical fires. Using Landsat data and the differenced Normalized Burn Ratio (dNBR) algorithm, the USGS Center for Earth Resources Observation and Science (EROS) and USDA-FS Remote Sensing Applications Center will map burn severity of all fires since 1984 greater than 202 ha (500 ac) in the east, and 404 ha (1,000 ac) in the west. The number of historical fires from this period combined with current fires occurring during the course of the project will exceed 9,000. The MTBS project will generate burn severity data, maps, and reports, which will be available for use at local, state, and national levels to evaluate trends in burn severity and help develop and assess the effectiveness of land management decisions. Additionally, the information developed will provide a baseline from which to monitor the recovery and health of fire-affected landscapes over time. Spatial and tabular data quantifying burn severity will augment existing information used to estimate risk associated with a range of current and future resource threats. The annual report of 2004 fires has been completed. All data and results will be distributed to the public on a Web site.

Factors in United States Forest Service district rangers' decision to manage a fire for resource benefit

United States wildland fire policy and program reviews in 1995 and 2000 required both the reduction of hazardous fuel and recognition of fire as a natural process. Despite the fact that existing policy permits managing natural ignitions to meet resource benefits, or Wildland Fire Use (WFU), most fuel reduction projects rely on mechanical treatments and prescribed fire. Budget constraints suggest that successful fuel and ecosystem management hinges on expanding WFU. The decision to authorise WFU in the US Department of Agriculture Forest Service (USFS) rests with line officers, and the so-called ‘go/no go’ decision constitutes a time-critical risk assessment. Factors influencing this decision clearly impact the viability of WFU. The present study examined influences on line officers’ go/no go decision. A telephone survey was conducted of all USFS district rangers with WFU authority in the Northern, Intermountain, and Southwestern Regions. The census was completed during February 2005 and obtained an 85% response rate. Data were analysed using Classification and Regression Tree analysis. Personal commitment to WFU provided the primary classifier for 91% of the district rangers who authorised WFU. External factors, negative public perception, resource availability, and a perceived lack of support from the USFS were the main disincentives to authorising WFU.

Guidelines to Engineering Analysis of Motorized Mixed Use on Low-Volume Roads in U.S. National Forests

In the past few decades, the availability and capability of off-highway vehicles (OHVs) have increased tremendously. On November 9, 2005, the U.S. Department of Agriculture (USDA) Forest Service published a final travel management regulation governing use of OHVs and other motor vehicles on National Forest System lands. The final rule requires individual national forests to designate those roads, trails, and areas open to motor vehicle use. For the USDA Forest Service to designate a road to be open for operation of both highway-legal and non-highway-legal vehicles at the same time (motorized mixed use), an engineering analysis must be performed. When motorized mixed-use designation is proposed for a road, a qualified engineer must determine whether that road can accommodate motorized mixed use, mitigation measures should be implemented before designation, or designation would be inappropriate. The guidelines that will be used by qualified engineers of the USDA Forest Service to analyze low-volume National Forest System roads are described, along with factors to be included in the analysis, possible mitigation measures, and documentation for motorized mixed-use analysis.