Prescribed fire alters structure and composition of a mid-Atlantic oak forest up to eight years after burning

Abstract Background Prescribed fire in Eastern deciduous forests has been understudied relative to other regions in the United States. In Pennsylvania, USA, prescribed fire use has increased more than five-fold since 2009, yet forest response has not been extensively studied. Due to variations in forest composition and the feedback between vegetation and fire, Pennsylvania deciduous forests may burn and respond differently than forests across the eastern US. We measured changes in forest structure and composition up to eight years after prescribed fire in a hardwood forest of the Ridge and Valley region of the Appalachian Mountains in central Pennsylvania. Results Within five years post fire, tree seedling density increased more than 72% while sapling density decreased by 90%, midstory density decreased by 46%, and overstory response varied. Following one burn in the mixed-oak unit, overstory tree density decreased by 12%. In the aspen–oak unit, where pre-fire harvesting and two burns occurred, overstory tree density increased by 25%. Not all tree species responded similarly and post-fire shifts in species relative abundance occurred in sapling and seedling size classes. Abundance of red maple and cherry species decreased, whereas abundance of sassafras, quaking aspen, black oak, and hickory species increased. Conclusions Forest composition plays a key role in the vegetation–fire relationship and localized studies are necessary to measure forest response to prescribed fire. Compositional shifts in tree species were most pronounced in the aspen–oak unit where pre-fire overstory thinning and two prescribed fires were applied and significant structural changes occurred in all stands after just one burn. Increases in fire-tolerant tree species combined with reductions in fire-intolerant species highlight the role of prescribed fire in meeting management objectives such as altering forest structure and composition to improve game habitat in mid-Atlantic hardwood forests.

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Effects of fire and thinning on Kansas oak woodlands

10.32469/10355/63574 ◽

2017 ◽

Author(s):

◽

Mary Faith Short

Keyword(s):

Prescribed Fire ◽

Sugar Maple ◽

Basal Area ◽

The United States ◽

Tree Density ◽

Canopy Openness ◽

First Year ◽

Herbaceous Plant ◽

Basal Diameter ◽

Advance Regeneration

Prior to Euro-American settlement, a mosaic of prairie, savanna, woodland, and forest existed within the Forest-Prairie Transition Region of the United States, with anthropogenic fire acting as an important driver in the perpetuation of open-oak communities. As fire suppression became a regular practice throughout the 20th century, these historically open communities became threatened by encroaching fire-sensitive, and often shade-tolerant, species. This study evaluated the effects of prescribed fire and thinning treatments as methods to achieve woodland restoration objectives, which commonly include reducing stand density, reducing mesophytic oak-competitors, increasing canopy openness, increasing herbaceous plant cover, and promoting the regeneration of oak. We investigated the effects of six treatment types on the structure and composition of a Kansas oak woodland. Treatments included: prescribed fire (burn), thin to 60 ft sq/acre basal area (T60), thin to 30 ft sq/acre basal area (T30), the combination of fire and thin to 60 ft sq/acre basal area (BT60), the combination of fire and thin to 30 ft sq/acre basal area (BT30), and an untreated control. Additionally, we examined the effect of fire on advance regeneration survival probability for five tree species: chinkapin oak (Quercus muehlenbergii), black oak (Q. velutina), bitternut hickory (Carya cordiformis), sugar maple (Acer saccharum), and eastern redcedar (Juniperus virginiana). Following a single girdle and herbicide application thinning treatment, we found low mortality in the first year, especially for sugar maple. As a result, the reduction in overstory basal area did not meet our intended targets. A single dormant season prescribed burn was effective at reducing large and small seedling densities of sugar maple and other oak-competitors, and increased forb and legume cover in the understory. However, the burn only treatment had no effect on overstory stand metrics, including basal area, tree density, percent stocking, and canopy openness. Thinning of the overstory and midstory in combination with prescribed fire resulted in similar effects to seedling densities and ground flora cover as the burn only treatment, but also created reduced tree density in the sapling layer and greater canopy openness. Additionally, the effect of the burn only treatment on advance regeneration revealed that significant relationships exist between pretreatment stem basal diameter and height and the probability of surviving a single fire for some of the species. These initial results are for the first year following treatments and over time we expect vegetation dynamics to continue to respond to treatments.

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Nitrogen Fertilization, Stand Age, and Overstory Tree Species Impact the Herbaceous Layer in a Central Appalachian Hardwood Forest

Forests ◽

10.3390/f12070829 ◽

2021 ◽

Vol 12 (7) ◽

pp. 829

Author(s):

Lacey J. Smith ◽

Kirsten Stephan

Keyword(s):

Community Composition ◽

Nitrogen Fertilization ◽

Tree Species ◽

Sugar Maple ◽

Diversity Indices ◽

Deciduous Forests ◽

Stand Age ◽

Herb Layer ◽

Herbaceous Layer ◽

Overstory Tree

Research Highlights: Herb-layer community composition, abundance, species richness, and Shannon–Wiener diversity index are shaped by nitrogen fertilization, disturbance history, and the overstory tree species in its immediate vicinity. Background and Objectives: While the herbaceous layer in deciduous forests is increasingly recognized for its importance in various aspects of forest ecosystem function, this study sought to describe the factors impacting the herbaceous layer. Specifically, this study’s objective was to quantify and compare herb-layer species composition, cover, and other community indices in watersheds with (a) different levels of N deposition, (b) different stand ages due to differing disturbance histories, and (c) different watershed aspects. This study also tested the hypothesis that herb-layer characteristics vary beneath tree species with contrasting nutrient dynamics (i.e., red and sugar maple). Materials and Methods: At the Fernow Experimental Forest in West Virginia (USA), the cover of all herb-layer species was recorded directly under nine red maple and nine sugar maple trees in each of four watersheds (WS): long-term fertilized WS3 and unfertilized WS7, both with a stand age of about 50 years, and two unmanaged watersheds with 110-year-old stands and opposite watershed aspects (south-facing WS10, north-facing WS13). Community composition and plot-level indices of diversity were evaluated with multivariate analysis and ANOVA for watershed-level differences, effects of the maple species, and other environmental factors. Results: In the fertilized watershed (WS3), herb-layer diversity indices were lower than in the unfertilized watershed of the same stand age (WS7). In the unfertilized watershed with the 50-year-old stand (WS7), herb-layer diversity indices were higher than in the watershed with the 110-year-old stand of the same watershed aspect (WS13). WS10 and WS13 had similar herb-layer characteristics despite opposite watershed aspects. The presence of sugar maple corresponded to higher cover and diversity indices of the herb-layer in some of the watersheds. Conclusions: Despite the limitations of a case study, these findings bear relevance to future forest management since the forest herb layer plays important roles in deciduous forests through its influence on nutrient cycling, productivity, and overstory regeneration.

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Effectiveness of prescribed fire as a fuel treatment in Californian coniferous forests

International Journal of Wildland Fire ◽

10.1071/wf06065 ◽

2009 ◽

Vol 18 (2) ◽

pp. 165 ◽

Cited By ~ 33

Author(s):

Nicole M. Vaillant ◽

Jo Ann Fites-Kaufman ◽

Scott L. Stephens

Keyword(s):

Prescribed Fire ◽

Forest Structure ◽

Tree Mortality ◽

Wildland Fire ◽

Fire Behavior ◽

Weather Conditions ◽

Fire Effects ◽

The United States ◽

Behavior Modeling ◽

Fuel Loads

Effective fire suppression and land use practices over the last century have altered forest structure and increased fuel loads in many forests in the United States, increasing the occurrence of catastrophic wildland fires. The most effective methods to change potential fire behavior are to reduce surface fuels, increase the canopy base height and reduce canopy bulk density. This multi-tiered approach breaks up the continuity of surface, ladder and crown fuels. Effectiveness of fuel treatments is often shown indirectly through fire behavior modeling or directly through monitoring wildland fire effects such as tree mortality. The present study investigates how prescribed fire affected fuel loads, forest structure, potential fire behavior, and modeled tree mortality at 90th and 97.5th percentile fire weather conditions on eight National Forests in California. Prescription burning did not significantly change forest structure at most sites. Total fuel loads (litter, duff, 1, 10, 100, and 1000-h) were reduced by 23 to 78% across the sites. The reduction in fuel loads altered potential fire behavior by reducing fireline intensity and increasing torching index and crowning index at most sites. Predicted tree mortality decreased after treatment as an effect of reduced potential fire behavior and fuel loads. To use limited fuel hazard reduction resources efficiently, more effort could be placed on the evaluation of existing fire hazards because several stands in the present study had little potential for adverse fire effects before prescribed fire was applied.

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Doing Justice, Preventing Crime

10.1093/oso/9780195320503.001.0001 ◽

2020 ◽

Author(s):

Michael Tonry

Keyword(s):

Structural Changes ◽

Minority Groups ◽

Political Influence ◽

Mass Incarceration ◽

The United States ◽

State Agencies ◽

Case Processing ◽

Three Strikes ◽

Moral Cost ◽

Main Ideas

In the 2020s, no informed person disagrees that punishment policies and practices in the United States are unprincipled, chaotic, and much too often unjust. The financial costs are enormous. The moral cost is greater: countless individual injustices; mass incarceration; the world’s highest imprisonment rate; extreme disparities, especially affecting members of racial and ethnic minority groups; high rates of wrongful conviction; assembly-line case processing; and a general absence of respectful consideration of offenders’ interests, circumstances, and needs. The main ideas in this book about doing justice and preventing crime are simple: Treat people charged with and convicted of crimes justly, fairly, and even-handedly, as anyone would want done for themselves or their children. Take sympathetic account of the circumstances of peoples’ lives. Punish no one more severely than he or she deserves. Those propositions are implicit in the rule of law and its requirement that the human dignity of every person be respected. Three major structural changes are needed. First, selection of judges and prosecutors, and their day-to-day work, must be insulated from political influence. Second, mandatory minimum sentence, three-strikes, life without parole, truth in sentencing, and similar laws must be repealed. Third, correctional and prosecution systems must be centralized in unified state agencies.

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Short- and long-term effects of ponderosa pine fuel treatments intersected by the Egley Fire Complex, Oregon, USA

Fire Ecology ◽

10.1186/s42408-019-0055-7 ◽

2019 ◽

Vol 15 (1) ◽

Cited By ~ 3

Author(s):

Jessie M. Dodge ◽

Eva K. Strand ◽

Andrew T. Hudak ◽

Benjamin C. Bright ◽

Darcy H. Hammond ◽

...

Keyword(s):

Prescribed Fire ◽

Vegetation Cover ◽

Tree Density ◽

Tree Canopy ◽

Fuel Treatments ◽

Dead Tree ◽

High Severity ◽

Short And Long Term ◽

One Year

Abstract Background Fuel treatments are widely used to alter fuels in forested ecosystems to mitigate wildfire behavior and effects. However, few studies have examined long-term ecological effects of interacting fuel treatments (commercial harvests, pre-commercial thinnings, pile and burning, and prescribed fire) and wildfire. Using annually fitted Landsat satellite-derived Normalized Burn Ratio (NBR) curves and paired pre-fire treated and untreated field sites, we tested changes in the differenced NBR (dNBR) and years since treatment as predictors of biophysical attributes one and nine years after the 2007 Egley Fire Complex in Oregon, USA. We also assessed short- and long-term fuel treatment impacts on field-measured attributes one and nine years post fire. Results One-year post-fire burn severity (dNBR) was lower in treated than in untreated sites across the Egley Fire Complex. Annual NBR trends showed that treated sites nearly recovered to pre-fire values four years post fire, while untreated sites had a slower recovery rate. Time since treatment and dNBR significantly predicted tree canopy and understory green vegetation cover in 2008, suggesting that tree canopy and understory vegetation cover increased in areas that were treated recently pre fire. Live tree density was more affected by severity than by pre-fire treatment in either year, as was dead tree density one year post fire. In 2008, neither treatment nor severity affected percent cover of functional groups (shrub, graminoid, forb, invasive, and moss–lichen–fungi); however, by 2016, shrub, graminoid, forb, and invasive cover were higher in high-severity burn sites than in low-severity burn sites. Total fuel loads nine years post fire were higher in untreated, high-severity burn sites than any other sites. Tree canopy cover and density of trees, saplings, and seedlings were lower nine years post fire than one year post fire across treatments and severity, whereas live and dead tree basal area, understory surface cover, and fuel loads increased. Conclusions Pre-fire fuel treatments effectively lowered the occurrence of high-severity wildfire, likely due to successful pre-fire tree and sapling density and surface fuels reduction. This study also quantified the changes in vegetation and fuels from one to nine years post fire. We suggest that low-severity wildfire can meet prescribed fire management objectives of lowering surface fuel accumulations while not increasing overstory tree mortality.

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‘Not bullet proof’: The complex choice not to seek a civil protection order for intimate partner violence

International Review of Victimology ◽

10.1177/0269758021993338 ◽

2021 ◽

Vol 27 (2) ◽

pp. 173-195

Author(s):

Jill Theresa Messing ◽

Meredith E Bagwell-Gray ◽

Allison Ward-Lasher ◽

Alesha Durfee

Keyword(s):

Intimate Partner Violence ◽

Legal System ◽

Partner Violence ◽

Structural Changes ◽

The United States ◽

Intimate Partner ◽

Access To Justice ◽

System Resource ◽

Survey Responses ◽

Protection Order

Protection orders (POs) are one legal system resource available to survivors of intimate partner violence. Many survivors choose not to obtain a PO, yet prior research has not examined the perspectives of these survivors. This study examined the open-ended survey responses ( n = 308) regarding the choice not to obtain a PO by survivors residing in emergency shelters in the United States. Content analysis indicated that many survivors made deliberate decisions to not seek safety through this venue. Survivors indicated that a PO may increase their partner’s violence, identified substantial barriers, evaluated a PO as unnecessary, preferred alternative strategies, were dealing with complex partner dynamics, and chose to protect their loved ones by not seeking a PO. Women with marginalized identities, in particular, indicated that there are multiple costs to seeking interventions within the legal system. Structural changes are needed within the legal system to facilitate access to justice for survivors.

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Facilitating Prescribed Fire in Northern California through Indigenous Governance and Interagency Partnerships

Fire ◽

10.3390/fire4030037 ◽

2021 ◽

Vol 4 (3) ◽

pp. 37

Author(s):

Tony Marks-Block ◽

William Tripp

Keyword(s):

Political Ecology ◽

Prescribed Fire ◽

Prescribed Burning ◽

Participant Observation ◽

Fire Suppression ◽

The United States ◽

Northern California ◽

Prescribed Burn ◽

California Department ◽

State Regulations

Prescribed burning by Indigenous people was once ubiquitous throughout California. Settler colonialism brought immense investments in fire suppression by the United States Forest Service and the California Department of Forestry and Fire Prevention (CAL FIRE) to protect timber and structures, effectively limiting prescribed burning in California. Despite this, fire-dependent American Indian communities such as the Karuk and Yurok peoples, stalwartly advocate for expanding prescribed burning as a part of their efforts to revitalize their culture and sovereignty. To examine the political ecology of prescribed burning in Northern California, we coupled participant observation of prescribed burning in Karuk and Yurok territories (2015–2019) with 75 surveys and 18 interviews with Indigenous and non-Indigenous fire managers to identify political structures and material conditions that facilitate and constrain prescribed fire expansion. Managers report that interagency partnerships have provided supplemental funding and personnel to enable burning, and that decentralized prescribed burn associations facilitate prescribed fire. However, land dispossession and centralized state regulations undermine Indigenous and local fire governance. Excessive investment in suppression and the underfunding of prescribed fire produces a scarcity of personnel to implement and plan burns. Where Tribes and local communities have established burning infrastructure, authorities should consider the devolution of decision-making and land repatriation to accelerate prescribed fire expansion.

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Over half of western United States' most abundant tree species in decline

Nature Communications ◽

10.1038/s41467-020-20678-z ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Hunter Stanke ◽

Andrew O. Finley ◽

Grant M. Domke ◽

Aaron S. Weed ◽

David W. MacFarlane

Keyword(s):

United States ◽

Tree Species ◽

Tree Mortality ◽

Temperate Forests ◽

Size Structure ◽

Forest Disturbance ◽

Population Decline ◽

Western United States ◽

Scale Transformation ◽

Forest Composition

AbstractChanging forest disturbance regimes and climate are driving accelerated tree mortality across temperate forests. However, it remains unknown if elevated mortality has induced decline of tree populations and the ecological, economic, and social benefits they provide. Here, we develop a standardized forest demographic index and use it to quantify trends in tree population dynamics over the last two decades in the western United States. The rate and pattern of change we observe across species and tree size-distributions is alarming and often undesirable. We observe significant population decline in a majority of species examined, show decline was particularly severe, albeit size-dependent, among subalpine tree species, and provide evidence of widespread shifts in the size-structure of montane forests. Our findings offer a stark warning of changing forest composition and structure across the western US, and suggest that sustained anthropogenic and natural stress will likely result in broad-scale transformation of temperate forests globally.

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Fire regime shift linked to increased forest density in a piñon–juniper savanna landscape

International Journal of Wildland Fire ◽

10.1071/wf13053 ◽

2014 ◽

Vol 23 (2) ◽

pp. 234 ◽

Cited By ~ 17

Author(s):

Ellis Q. Margolis

Keyword(s):

Regime Shift ◽

Fire History ◽

Fire Regime ◽

Fire Regimes ◽

Fire Frequency ◽

Climatic Conditions ◽

Tree Density ◽

High Severity ◽

Wide Range ◽

In Fire

Piñon–juniper (PJ) fire regimes are generally characterised as infrequent high-severity. However, PJ ecosystems vary across a large geographic and bio-climatic range and little is known about one of the principal PJ functional types, PJ savannas. It is logical that (1) grass in PJ savannas could support frequent, low-severity fire and (2) exclusion of frequent fire could explain increased tree density in PJ savannas. To assess these hypotheses I used dendroecological methods to reconstruct fire history and forest structure in a PJ-dominated savanna. Evidence of high-severity fire was not observed. From 112 fire-scarred trees I reconstructed 87 fire years (1547–1899). Mean fire interval was 7.8 years for fires recorded at ≥2 sites. Tree establishment was negatively correlated with fire frequency (r=–0.74) and peak PJ establishment was synchronous with dry (unfavourable) conditions and a regime shift (decline) in fire frequency in the late 1800s. The collapse of the grass-fuelled, frequent, surface fire regime in this PJ savanna was likely the primary driver of current high tree density (mean=881treesha–1) that is >600% of the historical estimate. Variability in bio-climatic conditions likely drive variability in fire regimes across the wide range of PJ ecosystems.

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Response of Deeproot Sedge (Cyperus entrerianus) to Herbicide and Prescribed Fire in Texas Coastal Prairie

Invasive Plant Science and Management ◽

10.1614/ipsm-d-14-00021.1 ◽

2015 ◽

Vol 8 (1) ◽

pp. 15-31 ◽

Cited By ~ 1

Author(s):

Jonathan R. King ◽

Andrew J. Bennett ◽

Warren C. Conway ◽

David J. Rosen ◽

Brian P. Oswald

Keyword(s):

Prescribed Fire ◽

Treatment Options ◽

Rapid Expansion ◽

Coastal Prairie ◽

Multiple Treatment ◽

Exotic Invasive Species ◽

Plant Groups ◽

Exotic Invasive ◽

Dormant Season ◽

In Fire

AbstractIntroduced accidentally from South America, deeproot sedge is rapidly expanding in a variety of habitats throughout the southeastern United States. Of particular concern is its rapid expansion, naturalization, and formation of monocultures in Texas coastal prairie, one of the most imperiled temperate ecoregions in North America. The objective of this research was to examine how deeproot sedge responds to prescribed fire, to the herbicide imazapic, and to treatment combinations of both. Combinations of prescribed fire and imazapic treatments and imazapic-only treatments effectively reduced deeproot sedge cover and frequency. However, plots exposed to dormant season fires (with no imazapic) had greater deeproot sedge cover after burn treatments were applied, indicating that coastal prairie management using only dormant season prescribed fire will not work toward reduction or management of this exotic invasive species. Although deeproot sedge cover was often reduced in fire–imazapic treatment combinations, it was still present in treatment plots. Moreover, desirable functional plant groups (i.e., native bunchgrasses) did not respond positively to the fire–imazapic treatments, but in some instances, woody plant coverage increased. Repeated, long-term approaches using integrated and coordinated efforts with multiple treatment options will be necessary to restore community structure to desired compositional levels. Such integrated approaches should be effective in reducing deeproot sedge frequency, cover, and extent to more manageable levels throughout its introduced geographic range.

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