Fire History of the Appalachian Region: A Review and Synthesis

The importance of fire in shaping Appalachian vegetation has become increasingly apparent over the last 25 years. This period has seen declines in oak (Quercus) and pine (Pinus) forests and other fire-dependent ecosystems, which in the near-exclusion of fire are being replaced by fire-sensitive mesophytic vegetation. These vegetation changes imply that Appalachian vegetation had developed under a history of burning before the fire-exclusion era, a possibility that has motivated investigations of Appalachian fire history using proxy evidence. Here we synthesize those investigations to obtain an up-to-date portrayal of Appalachian fire history. We organize the report by data type, beginning with studies of high-resolution data on recent fires to provide a context for interpreting the lower-resolution proxy data. Each proxy is addressed in a subsequent chapter, beginning with witness trees and continuing to fire-scarred trees, stand age structure, and soil and sediment charcoal. Taken together, these proxies portray frequent burning in the past. Fires had occurred at short intervals (a few years) for centuries before the fire-exclusion era. Indeed, burning has played an important ecological role for millennia. Fires were especially common and spatially extensive on landscapes with large expanses of oak and pine forest, notably in the Ridge and Valley province and the Blue Ridge Mountains. Burning favored oak and pine at the expense of mesophytic competitors, but fire exclusion has enabled mesophytic plants to expand from fire-sheltered sites onto dry slopes that formerly supported pyrogenic vegetation. These changes underscore the need to restore fire-dependent ecosystems

Temperature as a potent driver of regional forest drought stress and tree mortality

As the climate changes, drought may reduce tree productivity and survival across many forest ecosystems; however, the relative influence of specific climate parameters on forest decline is poorly understood. We derive a forest drought-stress index (FDSI) for the southwestern United States using a comprehensive tree-ring data set representing AD 1000–2007. The FDSI is approximately equally influenced by the warm-season vapour-pressure deficit (largely controlled by temperature) and cold-season precipitation, together explaining 82% of the FDSI variability. Correspondence between the FDSI and measures of forest productivity, mortality, bark-beetle outbreak and wildfire validate the FDSI as a holistic forest-vigour indicator. If the vapour-pressure deficit continues increasing as projected by climate models, the mean forest drought-stress by the 2050s will exceed that of the most severe droughts in the past 1,000 years. Collectively, the results foreshadow twenty-first-century changes in forest structures and compositions, with transition of forests in the southwestern United States, and perhaps water-limited forests globally, towards distributions unfamiliar to modern civilization

Advancing dendrochronological studies of fire in the United States

© 2018 by the authors. Licensee MDPI, Basel, Switzerland. Dendroecology is the science that dates tree rings to their exact calendar year of formation to study processes that influence forest ecology (e.g., Speer 2010 [1], Amoroso et al., 2017 [2]). Reconstruction of past fire regimes is a core application of dendroecology, linking fire history to population dynamics and climate effects on tree growth and survivorship. Since the early 20th century when dendrochronologists recognized that tree rings retained fire scars (e.g., Figure 1), and hence a record of past fires, they have conducted studies worldwide to reconstruct [2] the historical range and variability of fire regimes (e.g., frequency, severity, seasonality, spatial extent), [3] the influence of fire regimes on forest structure and ecosystem dynamics, and [4] the top-down (e.g., climate) and bottom-up (e.g., fuels, topography) drivers of fire that operate at a range of temporal and spatial scales. As in other scientific fields, continued application of dendrochronological techniques to study fires has shaped new trajectories for the science. Here we highlight some important current directions in the United States (US) and call on our international colleagues to continue the conversation with perspectives from other countries

Canons for Writing and Editing Manuscripts

Writing is much like any other activity-the more you read and write, the more proficient you become as a scientist. Here, I provide canons for writing and editing scientific papers that should help novice writers avoid common hazards that could render a manuscript unpublishable. Abstracts should be well-written and concise and contain all the major results and conclusions. The manuscript should be well organized. Sentences in all paragraphs should stick to the central theme of the paragraph. Writers should provide Latin names for species analyzed, and should use SI units in all cases. The use of bulleted lists, active voice, and commas after introductory phrases will improve the clarity of the manuscript. Tables and figures should be clear, well-organized, stand-alone accessories to the text, and usually convey data and results that are numerous or complex. Writers should avoid both plagiarism and self-plagiarism, and should have their manuscript proofread before submitting to a journal. Finally, authors should consult primary references (such as Scientific Style and Format, published by the Council of Biology Editors in 1994) to become familiar with troublesome words and phrases.This item is part of the Tree-Ring Research (formerly Tree-Ring Bulletin) archive. It was digitized from a physical copy provided by the Laboratory of Tree-Ring Research at The University of Arizona. For more information about this peer-reviewed scholarly journal, please email the Editor of Tree-Ring Research at [email protected]

An Updated List of Species Used in Tree-Ring Research

During the past 100 years, researchers have investigated the potential of hundreds of tree and shrub species for use in applications of tree-ring research. Although several lists of species known to crossdate have been published, investigated species that do not crossdate are rarely included despite the usefulness of this information for future research. This paper provides a list of the Latin and common names of 573 species that have been investigated in tree-ring research, information on species known to crossdate, and information on species with measurement and/or chronology data in the International Tree-Ring Data Bank. In addition, a measure of the suitability of a species for future tree-ring applications, the Crossdating Index (CDI), is developed and proposed for standard usage.This item is part of the Tree-Ring Research (formerly Tree-Ring Bulletin) archive. It was digitized from a physical copy provided by the Laboratory of Tree-Ring research at The University of Arizona. For more information about this peer-reviewed scholarly journal, please email the Editor of Tree-Ring Research at [email protected]

The 2008 Ameridendro Awards

This item is part of the Tree-Ring Research (formerly Tree-Ring Bulletin) archive. For more information about this peer-reviewed scholarly journal, please email the Editor of Tree-Ring Research at [email protected]

FHX2 - Software for Analyzing Temporal and Spatial Patterns in Fire Regimes from Tree Rings

Many studies use the temporal record of dendrochronologically-dated fire scars to document properties of fire regimes before human interference (e.g. fire suppression, logging, and agriculture) became pervasive. Such reconstructions provide vital information that can be used by land management agencies when designing and implementing fire management policies, and are especially useful for justifying the reintroduction of fire to areas where fire has long been excluded by humans. Tree-ring based fire history studies produce large quantities of data that require efficient tools for compilation, organization, and analysis. In this paper, I describe the development and use of FHX2, software comprised of individual modules designed specifically for (1) entering and archiving of fire history data, (2) creating graphs that display both temporal and spatial features of the site fire history, (3) conducting statistical analyses on fire intervals and seasonality, and (4) performing superposed epoch analysis to analyze climate /wildfire interactions. Although designed to analyze fire history, the software can be used to analyze any set of events recorded in the tree- ring record, such as growth suppressions and releases, floods, and insect outbreaks.This item is part of the Tree-Ring Research (formerly Tree-Ring Bulletin) archive. It was digitized from a physical copy provided by the Laboratory of Tree-Ring Research at The University of Arizona. For more information about this peer-reviewed scholarly journal, please email the Editor of Tree-Ring Research at [email protected]

A Manual and Tutorial for the Proper Use of an Increment Borer

An increment borer is the primary tool used to collect samples for dendrochronological analyses. These are precision instruments and users should be trained in their proper use, care, and maintenance. In this paper, I describe the various parts of an increment borer and how to keep these in working condition. I provide details on how to sharpen an increment borer, properly core a tree, check for core compression ("jamming"), extract the core, and store the core for transport. I provide tips on how to clear a jammed borer and remove a borer stuck in a tree. An important topic concerns the effects of boring on trees. The majority of studies indicate that conifers are minimally affected by both fungal decay and discoloration, whereas certain hardwood species can sustain major internal damage. Plugging the holes created by coring is unnecessary.This item is part of the Tree-Ring Research (formerly Tree-Ring Bulletin) archive. It was digitized from a physical copy provided by the Laboratory of Tree-Ring Research at The University of Arizona. For more information about this peer-reviewed scholarly journal, please email the Editor of Tree-Ring Research at [email protected]

Software Review

This item is part of the Tree-Ring Research (formerly Tree-Ring Bulletin) archive. It was digitized from a physical copy provided by the Laboratory of Tree-Ring Research at The University of Arizona. For more information about this peer-reviewed scholarly journal, please email the Editor of Tree-Ring Research at [email protected]

Book Review

This item is part of the Tree-Ring Research (formerly Tree-Ring Bulletin) archive. It was digitized from a physical copy provided by the Laboratory of Tree-Ring Research at The University of Arizona. For more information about this peer-reviewed scholarly journal, please email the Editor of Tree-Ring Research at [email protected]