Black Oak Research Articles

Monitoring of black oak (xánthiip) to center indigenous ecocultural revitalization

AbstractIndigenous Knowledge, Practice, and Belief Systems (IKPBS) are an ecological and cultural framework with which Indigenous communities have (and continue to) adaptively manage their land since time immemorial. In the current context of climate change and colonial forest and fire management in the western US, Indigenously‐led ecological research and cultural revitalization offers a path forward where tribal sovereignty of land stewardship is maintained and the resiliency of natural systems are reestablished. We describe our process of developing an Indigenous‐Directed Research (IDR) partnership to study xánthiip (Karuk for black oak, Quercus kelloggii), a Karuk cultural focal species, in the context of Karuk‐led forest restoration. We first outline our process of IDR by describing how this partnership was established, research questions and methodologies were co‐developed, IKPBS were centered, and utility to tribal forest restoration processes were prioritized. The primary product of this partnership was a culturally responsive black oak monitoring protocol to assess black oak tree quality over time. We describe how this protocol was developed including conducting semi‐structured qualitative interviews with Karuk cultural practitioners, translating qualitative interviews to field protocol metrics, consulting with research partners, testing for field feasibility, and sharing back to the local community through field training and youth curriculum development. Second, we analyzed plot data collected from the implementation of the black oak protocol using a two‐eyed seeing approach that ensured our ecological findings had cultural relevance for future Karuk‐led forest stewardship. Through this analysis we described the dominant black oak tree typologies based on their traits of importance as identified by Karuk cultural practitioners and research collaborators. All natural resources research takes place on Indigenous land. By outlining the steps of this transdisciplinary IDR partnership, we provide a framework for centering IKPBS, respecting Indigenous land sovereignty, and centering Indigenous leadership in ecological research and knowledge co‐development.

CentralBark Image Dataset and Tree Species Classification Using Deep Learning

The task of tree species classification through deep learning has been challenging for the forestry community, and the lack of standardized datasets has hindered further progress. Our work presents a solution in the form of a large bark image dataset called CentralBark, which enhances the deep learning-based tree species classification. Additionally, we have laid out an efficient and repeatable data collection protocol to assist future works in an organized manner. The dataset contains images of 25 central hardwood and Appalachian region tree species, with over 19,000 images of varying diameters, light, and moisture conditions. We tested 25 species: elm, oak, American basswood, American beech, American elm, American sycamore, bitternut hickory, black cherry, black locust, black oak, black walnut, eastern cottonwood, hackberry, honey locust, northern red oak, Ohio buckeye, Osage-orange, pignut hickory, sassafras, shagbark hickory silver maple, slippery elm, sugar maple, sweetgum, white ash, white oak, and yellow poplar. Our experiment involved testing three different models to assess the feasibility of species classification using unaltered and uncropped images during the species-classification training process. We achieved an overall accuracy of 83.21% using the EfficientNet-b3 model, which was the best of the three models (EfficientNet-b3, ResNet-50, and MobileNet-V3-small), and an average accuracy of 80.23%.

Nurturing Hope Through Reciprocity

Climate change has become a mainstream concern, with proposed solutions focusing on mitigating the impact of environmental degradation on human lives. I use Toronto’s High Park as a case study to explore why an essential aspect of achieving profound and enduring environmental restoration involves recognizing the deep interconnectedness between human beings and what we commonly refer to as “nature”. High Park’s black oak savannah was managed for thousands of years by Indigenous peoples, who used fire to maintain the savannah’s open canopy and activate seeds. European colonization halted these burns, leading to most of the savannah being lost to closed-canopy forests and invasive plants; globally, less than one percent of oak savannah ecosystems remain. Amid despair, we rekindle our hope through prescribed burns, stewardship programs, and the planting of grasses and wildflowers with long-stand relationships with the land; we know that hope is a discipline where collective commitment and action are essential. Indigenous knowledge and storytelling remind us of our responsibility of reciprocity to the land and all our relations. We sow these seeds of hope and trust they will flourish and generate new life, much like ancestral seeds activated by fire.

Deciphering the role of fungi in post-fire succession in Canada's Great Lakes–St. Lawrence forest region

Fungi are important drivers of forest health, as well as culturally important for many Indigenous communities. In Canada, increasingly intense and frequent wildfires affect fungal substrates and habitats, environmental conditions, and physiological responses of hosts with which fungi may interact. In Ontario, aggressive fire suppression raises the question of how fungal regeneration, and taxonomic compositions, may be affected when fires do appear on the landscape. This study investigates the fungal regrowth post-fire above and below-ground and the role fungal species play in post fire ecological succession in Southeastern Ontario. The study sites are two black oak savannas in restoration, previously prescribed a burn (Northumberland County, 2022 and 2023), and a recent wildfire burned mixed deciduous forest (Centennial Lake, 2023). We collected fruiting body and soil samples for fungal identification via observational and DNA methods. Above ground vegetation assays were made at 9 burned plots within these three sites and another 8 adjacent unburned (control) plots. We extracted soil DNA and will amplify fungal ITS2 amplicons by PCR. Then, we will sequence the amplified DNA using MiSeq to compare burned and unburned soil fungi. Lastly, we will use statistical methods to differentiate effects from fire and soil texture and type in burned and control plots. Thus far, we found that Pyropyxis rubra, a pyrophilous ascomycete fungus, is extremely abundant just weeks after the lightning-induced fire at Centennial Lake. Our combined observational and quantitative descriptions of above-and below ground soil fungi provide a deeper understanding of how fire affects species composition, fungal reproduction, and population dynamics in Ontario. This research may help inform other successional processes, and fungal harvesting of culturally important species.

Early Responses to Crown Modification of California Black Oak Sprouts Initiated by High-Severity Wildfire

Abstract Hardwoods resprouting after wildfire or cutting develop as multistemmed clumps that gradually self-thin over time. There is increasing interest in thinning of sprouting species to accelerate the formation of tree characteristics important to indigenous cultural practices and wildlife such as large-diameter stems, large branches, broad crowns, and acorn production. We compared responses to three thinning treatments applied to black oak (Quercus kelloggii) resprouting after high-severity wildfire throughout northern California, USA. Basal area increment of the dominant stem was greatest after only one stem was retained, intermediate after three stems were retained, and lowest within unthinned oaks. Unwanted resprouting in response to the thinning was minimized by retaining three stems. Acorn production tended to increase as time elapsed since the fire (i.e., larger, older sprouts) but varied among sites and was noted as early as six years after fire at one site. More study is needed to test for the effects of thinning timing and intensity on the acceleration of acorn production as well as stem, branch, and crown size development over time.

Seasonal changes in foliar calcium oxalate concentrations in conifer and hardwood trees: a potentially bioavailable source of cellular calcium and/or oxalate under stress

The present study compared seasonal changes in the concentrations of calcium oxalate (CaOx) crystals and total calcium (Ca) in the foliage of red spruce (Picea rubens Sarg.), white pine (Pinus strobus L.), black oak (Quercus velutina L.), and sugar maple (Acer saccharum Marshall) trees. Samples were collected from the same four replicate trees of each species starting in June 2014 through September 2015 for a total of six times for conifers and four times for hardwoods. Calcium oxalate was extracted from tissues using a method developed in our laboratory in 2015. The purity of the extracted CaOx was indicated by an r2 of 0.98 between Ca and oxalate (Ox) for the data pooled across all species and all sampling times. As expected, the concentrations of CaOx varied between species. We hypothesized that the only role of CaOx crystals is to bind excess Ca, so based on this hypothesis the concentrations of CaOx would increase over the growing season both in conifer and hardwood trees, and in conifers, its quantities would be higher in the older relative to the younger needles. However, we found, that for most species, CaOx concentrations were not significantly different from each other for all collection times. In addition, relative to total Ca, the percent of Ca that existed in the form of CaOx varied widely with species, time of collection within a species, and needle age. Thus, no specific trend was observed for CaOx accumulations with changes in seasons. Concentrations of CaOx were indeed higher in older spruce and pine needles. Based on the available literature on this topic and our data, this could mean that CaOx amounts are dynamic and are continuously being adjusted according to the metabolic needs of cells for either Ca or Ox while still performing the function of shedding off excess Ca.

First Report of the Armillaria Root Disease Pathogen, Armillaria solidipes, on Black Oak (Quercus velutina) in North Carolina, USA.

Armillaria root disease is among the largest causes of mortality and lost productivity of widely ranging horticultural, urban, and forest trees/shrubs in diverse boreal, temperate, and tropical regions around the world (Kim et al. 2022). Damage from Armillaria root disease will likely increase in response to changing climate and extreme weather because environmental stress can predispose host trees to Armillaria root disease (Murray and Leslie 2021; Kim et al. 2021). On August 14, 2021, a mature black oak (Quercus velutina) ca. 29 m in height and 64 cm DBH experienced a complete structural failure originating at the root plate, falling onto a major highway within the Pisgah National Forest near Brevard, North Carolina (35°16'50.876"N, 82°42'51.785"W, elevation 680 m) during sunny, calm conditions. No above-ground indications of predisposing disturbance, injury, or insect/disease activity were observed. Advanced wood decay, however, was present in many structural roots of the exposed root plate; abundant rhizomorphs attached to the surfaces of most roots were noted (Supplemental Figure 1). One large primary root (ca. 23 cm in diameter) exhibited clear signs of Armillaria root disease at the point of failure as evidenced by an extensive decay column, abundant black rhizomorphs on the root surface, and white mycelial fans (a sign of pathogenicity) within the root itself (Supplemental Figure 1). Rhizomorph samples were established in culture, two Armillaria isolates (PNF#001R-1 and PNF#001R-2) were examined, and pairing tests showed that both isolates belonged to the same genet (PNF#001R-1 = PNF#001R-2). Based on translation elongation factor 1α (tef1) sequences, both isolates (one genet) were identified as A. solidipes (GenBank accession no. OP823701), showing 98% similarity with A. solidipes tef1 sequences (e.g., MH879015) in GenBank. Also, nine replications of somatic incompatibility tests of the isolate with five North American Armillaria spp. [A. solidipes, A. mellea, A. gallica, A. mexicana, and Desarmillaria caespitosa (= North American A. tabescens)] showed 67% compatibility with A. solidipes, compared with 0-22% for A. mellea, D. caespitosa, A. gallica, and A. mexicana. All test species but A. mexicana are reported to occur in the eastern and/or southern USA, while A. mexicana occurs in a similar environment in Mexico (Elías-Román et al. 2018). To our knowledge, this is the first confirmed report of A. solidipes in North Carolina, USA, where it was causing disease on black oak, and this is the most southerly confirmed case of A. solidipes in eastern North America. Although Armillaria inoculation tests are impractical, black oak was previously reported as a host of A. solidipes in Massachusetts, USA (Brazee and Wick 2009). Armillaria solidipes is considered as the most important Armillaria root disease pathogen of conifer forests in western USA (Lockman and Kearns 2016), but it has been suggested that A. solidipes can thrive in northern hardwood forests that reside near conifer forests (Brazee and Wick 2009). Climate change is predicted to increase damage caused by A. solidipes on conifers in the western USA (Kim et al. 2021); however, it is undetermined if the occurrence of A. solidipes-caused disease in North Carolina is related to climate change or how climate change could influence this disease across the region. More surveys are needed to assess the impact of Armillaria root disease on health of mixed forests in the eastern USA.

Degradation and restoration of Indigenous California black oak (Quercus kelloggii) stands in the northern Sierra Nevada

BackgroundThe cultural connections of the Maidu to the lands they inhabit are profound with burning being a major component of their culture. California black oak plays an important role in the lifeways of many Indigenous tribes and Native peoples tend black oaks. We used multiple lines of evidence to reconstruct Indigenous fire use in a mixed conifer forest in the northern Sierra Nevada. This includes summarizing oral traditions by the Mountain Maidu, quantifying current and historical forest structure, and characterizing fire effects in an area impacted by the 2021 Dixie Fire.ResultsThe promotion of fire, both lighting- and human-ignited, has always been part of Mountain Maidu land stewardship. The mixed conifer forests in our focal study site had very high tree densities that were dominated by small, shade-tolerant species and the historic mean fire return interval was 8.6 years. Twenty-three fire intervals of 10 years or less and 11 fire intervals of 5 years or less were recorded. Based on forest inventory data collected in 1924, a majority of the forests in the broader region surrounding our focal site (82%) did not experience high levels of conifer competition. This is a stark contrast to contemporary forest conditions which showed that 73% of forests either were experiencing full site occupancy or were within the zone of imminent mortality. Contemporary forests not experiencing high levels of conifer competition had the highest density of large California black oak while forests in the zone of imminent mortality had the lowest density of large California black oak.ConclusionsFire exclusion and suppression led to a slow, albeit catastrophic, shift for California black oaks. The mixed conifer forests sampled in the early 1920s had very low tree densities and were dominated by large ponderosa and sugar pine trees which would have allowed California black oak to thrive. The number of very short fire intervals recorded is difficult to explain by lightning alone, pointing to the management of this area for Indigenous purposes. The 2021 wildfire resulted in 100% mortality of all conifer trees in the area but 61% of the California black oaks resprouted. This provides an opportunity to remove the conifer snags and allow the California black oaks to regain dominance. It would take active stewardship to produce the oak dominance again but it is possible and could be co-led by the Maidu and federal managers.

Spatial Bayesian models project shifts in suitable habitat for Pacific Northwest tree species under climate change

AbstractWe developed spatial Bayesian hierarchical models to assess potential climate change impacts on suitable habitat for five important tree species in the Pacific northwestern United States (California, Oregon, and Washington). Individual‐species models were fit with presence–absence data from forest inventory field plots and spatial relationships were specified through a conditional autoregressive model. This modeling approach allowed us to visualize uncertainty in response curves, map current and future prediction uncertainty, and provide interval estimates for change. Upward elevational or northward latitudinal shifts in climatically suitable habitat were projected for all species. Climate change impacts were the most damaging for noble fir (Abies procera), for which 79%–100% of the current range was projected to become climatically unsuitable by the 2080s. Although coastal Douglas‐fir (Pseudotsuga menziesii var. menziesii) has been projected by others to gain habitat in Canada, within our study area we projected a net loss of climatically suitable habitat (ca. 8000–31,400 km2) under three of four future climate scenarios. A net loss in habitat was also projected for Oregon white oak (Quercus garryana) under three of four scenarios, with 40%–60% of the current range becoming unsuitable. Although there was no net loss of habitat for forest land blue oak under any scenario, other factors like competition may inhibit blue oak (Quercus douglasii) and white oak from occupying areas projected to increase in climatic suitability. Additionally, between 13% and 32% of blue oak's current range was projected to become unsuitable; some of these areas aligned with dieback following the 2012–2015 California drought, which our data set predates. Unlike the other four species, we projected a 17%–25% increase in climatically suitable habitat for California black oak (Quercus kelloggii), although 1%–20% of the current range was still projected to become unsuitable. Our findings indicate that, although some species will face more pressure in tracking climatically suitable habitat than others, climate change will impact the location of suitable habitat for many species.

Carolina's Golden Fields: Inland Rice Cultivation in the South Carolina Lowcountry, 1670–1860

In Carolina's Golden Fields, Hayden Smith delivers a long overdue assessment of inland rice culture's importance to the South Carolina Lowcountry. Due to a dearth of primary sources and the fact that most inland rice fields have been lost to reforestation and development, historians have overlooked inland rice cultivation or have viewed it as a primitive stage of rice cultivation when compared to tidal cultivation. Rather, as Smith's work demonstrates, inland rice cultivation required planters and enslaved laborers to exercise precise knowledge of topography and hydrology to render their harvests profitable. The utilization of this knowledge began when free and enslaved Carolinians experimented with rice alongside other grains as a subsistence crop, first relying on the “providence” method and then realizing the advantages of impervious soils and water management. Using Pooshee, Newington, and Charleywood plantations as examples in chapter 2, Smith demonstrates how rice planters and enslaved laborers adapted to and manipulated varied microenvironments to make cultivation successful and ultimately create a foundation for South Carolina's colonial economy and the expansion of slavery. With the foundation set in the first decades of the eighteenth century, land acquisition and a stable market prompted rice planters to engage in ever more elaborate schemes for irrigation and drainage that mirrored new strategies being used for tidal cultivation. As Smith discusses in chapter 3, this intensive stage of development resulted in higher profits, increased demand for labor, and susceptibility to malaria, freshets, and declining soil fertility. Consequently, planters increasingly perceived the environment as unhealthy and downright hostile.Nevertheless, inland rice cultivation persisted throughout the antebellum period and contributed to the evolution of the Lowcountry's agricultural regime. Focusing on four Wando River plantations in chapter 4, Smith notes how rice planters expanded their landholdings in the post–Revolutionary War era in order to access water and have enslaved laborers construct reservoirs and canals. Smith's microanalysis of each plantation illuminates his earlier theme that this work required knowledge of topography and hydrology to make rice cultivation profitable. It also involved constant experimentation with planting strategies to maintain crop yields. For some planters, successful inland rice cultivation also provided a potential avenue into the Lowcountry aristocracy. Locked out of the more expensive tidal plantation market, social aspirants like Mathurin Gibbs and John Irving saw inland rice as a means to establish their status as planters. As chapter 5 makes clear, despite ambition and the knowledge of experienced overseers, their efforts were frustrated by environmental limitations and small labor forces. Indeed, Gibbs succumbed to malaria in 1849. Yet agricultural reformers espoused inland rice as a way to diversify their planting portfolio when the fertility of their cotton lands declined in the two decades preceding the Civil War. In chapter 6, Smith focuses on Middle Saint John's Berkeley Parish where the Black Oak Agricultural Society promoted scientific experimentation and planters had access to the numerous inland swamps and freshwater springs in Biggin Basin. These reform efforts never amounted to much, but the attempt to revive inland rice testified to its persistence as a symbol of economic salvation.With emancipation, large-scale rice cultivation collapsed and former inland rice lands returned to forest. Purchased by timber companies or converted to subdivisions in the twentieth century, little remains of the inland rice infrastructure that Smith describes throughout the book. However, drawing from plantation ledgers, manuscripts, agricultural journals, deeds and plats, geological and archaeological reports, and myriad other primary and secondary sources, Smith rescues inland rice cultivation from obscurity and gives it a central place in South Carolina's environmental history. Moreover, Hayden Smith has walked the land he describes, and Carolina's Golden Fields exemplifies his intimate knowledge of the Lowcountry, past and present, as well as his skill as a historian. His astute attention to the terrain of forest and history make this a readable, informed, and important contribution to the historiography of rice, slavery, and the environment.

Is foliar tissue drying and grinding required for reliable and reproducible extraction of total inorganic nutrients? A comparative study of three tissue preparation methods.

In response to abiotic and biotic stress or experimental treatment(s), foliar concentrations of inorganic nutrients and metabolites often change in concert to maintain a homeostatic balance within the cell's environment thus allowing normal functions to carry on. Therefore, whenever possible, changes in cellular chemistry, metabolism, and gene expressions should be simultaneously evaluated using a common pool of tissue. This will help advance the knowledge needed to fill the gaps in our understanding of how these variables function together to maintain cellular homeostasis. Currently, foliar samples of trees for total inorganic nutrients and metabolic analyses are often collected at different times and are stored and processed in different ways before analyses. The objective of the present study was to evaluate whether a pool of wet (previously frozen) intact tissue that is used for metabolic and molecular work would also be suitable for analyses of foliar total inorganic nutrients. We compared quantities of nutrients extracted from wet-intact, dried-intact, and dried-ground tissues taken from a common pool of previously frozen foliage of black oak (Quercus velutina L.), sugar maple (Acer saccharum Marshall), red spruce (Picea rubens Sarg.), and white pine (Pinus strobus L.). With a few exceptions in the case of hardwoods where concentrations of total Ca, Mg, K, and P extracted from wet-intact tissue were significantly higher than dry tissue, data pooled across all collection times suggest that the extracted nutrient concentrations were comparable among the three tissue preparation methods and all for species. Based on the data presented here, it may be concluded that drying and grinding of foliage may not be necessary for nutrient analyses thus making it possible to use the same pool of tissue for total inorganic nutrients and metabolic and/or genomic analyses. To our knowledge, this is the first report on such a comparison.

Forests at the fringe: Comparing observed change to projected climate change impacts for five tree species in the Pacific Northwest, United States

Rapid climate change over the coming century will impact suitable habitat for many tree species. In response to these changes in climate, areas that become unsuitable will see higher mortality and lower growth and recruitment. Therefore, early detection of demographic trends is critical for effective forest management. Recent 10-year remeasurement data from the United States (US) Department of Agriculture (USDA) Forest Service’s Forest Inventory and Analysis (FIA) Program’s national annual inventory of forest land provides an ideal data set for analyzing such trends over large areas. However, failure to distinguish between areas of future habitat contraction and expansion or persistence when estimating demographic trends may mask species’ shifts. We used remeasurement data to compare observed tree demographic rates with projected impacts of climate change for five important tree species in the Pacific Northwest. Projected impacts were based on spatial-Bayesian hierarchical models of species distributions, which were used to project areas where habitat would persist (remain climatically suitable), expand (become suitable), or contract (become unsuitable) under four future climate scenarios for the 2080s. We compared estimates of mortality and net-growth between these areas of shifting suitability and a naïve division of habitat based on elevation and latitude. Within these regions, we assessed the sustainability of mortality and determined that observational data suggest that climate change impacts were already being felt in some areas by some species. While there is an extensive literature on bioclimatic species distribution models, this work demonstrates they can be adapted to the practical problem of detecting early climate-related trends using national forest inventory data. Of the species examined, California black oak (Quercus kelloggii) had the most notable instances of observed data suggesting population declines in the core of its current range.

Characteristics of Dry-Mesic Old-Growth Oak Forests in the Eastern United States

Dry-mesic old-growth oak forests are widely distributed remnants across the eastern U.S. and are expected to increase in number and extent as second-growth forests mature. In this study, we synthesize published and unpublished information to better define the species, structure and extent of these forests. Mean site tree density for trees ≥10 cm dbh ranged from 341–620 trees ha−1. In the eastern part of the region, most stand basal areas were >23 m2 ha−1, compared to ≤23 m2 ha−1 in the westernmost stands. Overall, woody species diversity was relatively low compared to old-growth oak forests on moister sites, with tree species per forest ranging from 5–18. The most common species among the stands were white oak (Quercus alba), northern red oak (Quercus rubra), and black oak (Quercus velutina). Shrub and vine species per forest ranged from 1–10, with common species or genera including Virginia creeper (Parthenocissus quinquefolia), poison ivy (Toxicodendron radicans), Vaccinium spp., and grapevines (Vitis spp.). Within the southern Appalachian Mountains, rosebay rhododendron (Rhododendron maximum) and mountain laurel (Kalmia latifolia L.) were common. Herbaceous species per stand ranged from 4–51, with the highest richness occurring in a southern Appalachian oak-hickory forest. The maximum within-stand age of the large trees ranged from 170 to over 365 years. The mean density of standing dead trees ≥10 cm dbh ranged from 31–78 ha−1 and the volume of coarse woody debris ≥10 cm in diameter averaged 52 m3 ha−1. We more fully describe the characteristics of these forests and fill gaps in the collective knowledge of this increasingly important forest type. However, over the past 20 years, there has been scant research on these forests, and older research studies have used a variety of research plots and methods. A uniform approach to surveying these sites is needed to gain a better understanding of these forests before we are faced with caring for an increase in old-growth forest areas.

Sap flow velocities of Acer saccharum and Quercus velutina during drought: Insights and implications from a throughfall exclusion experiment in West Virginia, USA

Forest species composition mediates evapotranspiration and the amount of water available to human-use downstream. In the last century, the heavily forested Appalachian region has been undergoing forest mesophication which is the progressive replacement of xeric species (e.g. black oak (Quercus velutina)) by mesic species (e.g. sugar maple (Acer saccharum)). Given differences between xeric and mesic species in water use efficiency and rainfall interception losses, investigating the consequences of these species shifts on water cycles is critical to improving predictions of ecosystem responses to climate change. To meet this need, we quantified the degree to which the sap velocities of two dominant broadleaved species (sugar maple and black oak) in West Virginia, responded to ambient and experimentally altered soil moisture conditions using a throughfall exclusion experiment. We then used these data to explore how predictions of future climate under two emissions scenarios could affect forest evapotranspiration rates. Overall, we found that the maples had higher sap velocity rates than the oaks. Sap velocity in maples showed a stronger sensitivity to vapor pressure deficit (VPD), particularly at high levels of VPD, than sap velocity in oaks. Experimentally induced reductions in shallow soil moisture did not have a relevant impact on sap velocity. In response to future climate scenarios of increased vapor pressure deficits in the Central Appalachian Mountains, our results highlight the different degrees to which two important tree species will increase transpiration, and potentially reduce the water available to the heavily populated areas downstream.

Recurring wildfires provoke type conversion in dry western forests

AbstractRecent wildfires across western North America have burned with uncharacteristically high severity, representing a substantial departure from natural fire regimes. In mixed‐conifer and pine–oak ecosystems of the southern Cascade Range, widespread shifts in stand structure and composition have led to a diversity of post‐wildfire vegetation responses. When recent wildfire “footprints” reburn in subsequent fires, their recovery pathways are complex. In order to understand the effects of overlapping mixed‐severity fires, we quantified changes in overstory and midstory structure and species composition for time periods prior to and following two large overlapping wildfires in the southern Cascades: the 2000 Storrie and 2012 Chips Fires. Plots were stratified into 16 severity combinations (unburned, low, moderate, and high in the Storrie Fire combined with the same four categories in the Chips Fire: e.g., moderate Storrie/high Chips) across the 9000‐ha overlapping burned area. Following the two fires, tree quadratic mean diameter and stand density declined for most species, but changes were species‐specific. Compared with preburn values, importance values for fire‐sensitive white fir (Abies concolor) were reduced by 66%, while resprouting fire‐resilient California black oak (Quercus kelloggii) importance values increased by 37% in severity combinations that included at least one high‐severity fire. Greatest shifts were documented in sites that burned twice at high severity, where resulting vegetation was dominated by oak sprout clumps and resprouting and fire‐stimulated montane chaparral species, while unburned and low‐severity strata retained a substantial component of Douglas‐fir (Pseudotsuga menziesii) and white fir. Results suggest that repeated moderate‐ and high‐severity fires can result in ecosystem state shifting toward fire‐resilient oak‐shrub communities in this fire‐prone landscape. Managers seeking greater landscape resilience can implement treatments such as thinning and prescribed burning, while taking advantage of fire‐created patches such as these in areas where the likelihood of a hotter and drier future makes the reestablishment of continuous forest cover unrealistic.

Canopy Cover and Canopy Heterogeneity Drive Plant Alpha Diversity But Not Beta Diversity in a Midwest Oak Savanna

Midwest oak savannas contain some of the highest plant diversity in the United States and are among the rarest terrestrial ecosystems globally. Consequently, understanding diversity patterns within these ecosystems is important for setting management and restoration goals. This study aimed to understand the role of canopy cover and heterogeneity in canopy cover in influencing plant alpha and beta diversity within oak savanna ecosystems. This study took place in the black oak savannas of the Indiana Dunes along the southern shores of Lake Michigan in NW Indiana, USA. We sampled twenty-nine 1000 m2 plots with gradients in canopy cover and canopy heterogeneity across the Indiana Dunes to examine the influence of canopy cover and canopy heterogeneity on plant diversity. Woody plant alpha diversity was highest in areas with a high canopy cover (>75%). C3 graminoids, C4 graminoids, and sedge alpha diversity were highest in low canopy cover areas (<25%). Forb and legume alpha diversity were highest with low to intermediate canopy cover (25–50% and 20–35%). Overall, plant alpha diversity was highest at intermediate canopy cover. High canopy heterogeneity was associated with high alpha diversity. There was no relationship between canopy cover or canopy heterogeneity with beta diversity. However, beta diversity was exceptionally high within all sites. An average canopy cover of 25–50% is the optimal cover for promoting high plant diversity across many functional groups. Still, low and high canopy cover sites are also important for maximizing diversity of some functional groups. Therefore, we recommend managing oak savannas for 25–50% canopy cover to maximize diversity, but where opportunities exist in large remnants of oak savanna, maintaining some areas with few trees and other areas with closed canopies can maximize diversity on a landscape scale.

변산반도국립공원 꽝꽝나무군락의 생태적 특성

In order to preserve and restore the habitats of Ilex crenata community distributed in Byeonsanbando National Park, the ecological characteristics of flora and major vegetation were investigated centered on the community distribution area. A total of 36 taxa with 22 families, 21 genera, 32 species, and 4 variants, were investigated in the vicinity of the Ilex crenata community. At close distances centered on the area around the Ilex crenata community, the vegetation was found to be a mountain coniferous forest called Pinus densiflora-Quercus serrata community(35° 39′ 18.62″ north latitude, 126° 34′ 56.70 east longitude), at an elevation of 85m to 95m above sea level, an inclination of 10° to 15°, and clustered around the south and southwest slopes. In the Tree-1 layer, there are Pinus densiflora, Quercus serrata, Quercus variabilis, and Prunus serrulata var. pubescens. In the Tree-2 layer, there are Quercus serrata, Quercus variabilis, Prunus serrulata var. pubescens, Styrax japonicus, and Acer pseudo-sieboldianum. In the Shrub layer, there are Ilex crenata, Rhododendron mucronulatum, Lespedeza maximowiczii, Fraxinus sieboldiana, Smilax china, Lindera obtusiloba, Fraxinus rhynchophylla, Rhododendron schlippenbachii, Lindera glauca, Juniperus rigida var. rigida. In the past, before the Buam Dam was built, the surrounding area was a rice paddy field and farmland, but after the Buam Dam was completed, due to changes in the climatic environment, such as fog and humidity, which occurred around the Buan Dam, It is predicted that changes in species composition within the community will appear as the blooming of Quercus serrata increases in the Tree-1 layer and Tree-2 layer, as Fraxinus sieboldiana, Fraxinus rhynchophylla, Lindera obtusiloba, etc. appear in the shrub layer, and Sasa borealis Indigofera kirilowii, Carex lanceolata, and Fraxinus sieboldiana, etc. appear in the herb layer. The distribution area of Ilex crenata community was measured to be 384㎡, the height of Ilex crenata was in the range of 2.2 to 2.5m, and the diameter of the rhizome of Ilex crenata community was Ø48.5mm+39.4mm+46.9mm+37.3mm, It is considered to be in good growth condition due to the stable management and protection of the colony area. In addition, as it is expected that Ilex crenata community will gradually spread as a constituent species of the shrub layer and the herbaceous layer in the pine and Ilex crenata community communities near the native habitats of the black oak community, a detailed investigation into these areas and monitoring for continuous conservation and restoration are needed in the future.

Felling, and: Supper Poem, and: His Body Cut through the World like a Cold Wind, and: Love Poem

Felling, and: Supper Poem, and: His Body Cut through the World like a Cold Wind, and: Love Poem Kelan Nee (bio) Felling The girl in Dickey Bub working the register looked at me likeI was food. She couldn't have been older than fifteen.She watched me leave and drive away. I was going to be alone.Among the trees which were easy with me. I saw a boy with a gunas big as his body, stood butt-end up; a spotted dog, curled,sleeping on top of a truck; a woman who sold me two dozen eggsfrom inside of her house; a beagle, brain bashed, tossedon the side of the road like salt. Everything made me sad.I was used to this kind of driving sadness that made me believethat being alive was unbearable and the only thing worth doing.I ran a saw for two days, dropped what must've been thirty trees.Post oak. Shortleaf pine. Black oak. Catalpa. Post oak. Post oak.My body felt useful again and my mind quiet. In the morning,I ate eggs and kicked my feet into boots. At night, I ate eggsand looked up. I didn't feel bad felling trees, though they had donenothing to deserve falling. In the city, I had someone waiting for me.There I had forgotten color and silence, and I had only been a mindmade of words, and yet, with her, my body had roots. I thought of herendlessly. I ate sixteen eggs in two days. I breathed heavierthan I should have. I sat in the woods when I couldn't lift my arms.Years before, in the forest in Maine, I lived alone. I would fill a bucketwith water from a spring and pour it over myself. My bare bodylike a field. Once, I was watched. Hikers, making their way off trail.I turned to grab my towel from a branch. They smiled and said hello.I said it back. Sitting against a stump this week, I thought of them,my chest heaving, my body a ziggurat of salt. In the morning I droveto Iron County. The man in the hardware store, camo-clad and hulking,looked at me like a deer. I needed something to kill rats, whose tailshad been thrumming through the night. He showed me the poison, [End Page 95] a bar of dust and glue. Unwrapped it, held it up to his mouth. Winked.I didn't go back to the cabin. I didn't want to be useful. I didn't wantthe trees. I drove fast, back to her, who made me breathless, afraid.Who made me believe I was good, and my body could be enjoyed. [End Page 96] Supper Poem My father comes to me now in dreams and thin strips of tomatoes,always with his neck broken and his head hanging to the side,wearing his noose like a tie. It's been ten years since he died. For his birthday, I'll probably cook. I would stay with himwhen I was young and he played sober well enough to fool my mom.He'd pick me up on days off from the restaurant where he worked as a line cook and snuck drinks from behind the bar. Beforehe got fired, and sober for the next to last time, he broke in, drankas much as his body could bear. They found him on the floor, sweat glistening on his face like it does on empty bottlesof liquor and wine. Back then, he rarely cooked for me.Spent his money elsewhere, on things that he knew better than to give to his son. More than once for supper, he pulled a barof chocolate from his coat, Hershey's Special Dark, and broke halfoff for him and half for me. He'd put both squares between slices of white bread and put on a Bruce Springsteen record. We took bites,his big and mine small. We'd drink cream soda. He used to take meup in his arms like I was made of cloth and...

DOZER LINES INFLUENCE POST-FIRE PLANT COMMUNITY RECOVERY

As wildfires increase in extent and intensity and threaten local communities, active suppression tactics are becoming more common, including the creation of fire lines. Post-fire, these sites can become populated with non-native species and risk type conversion if native species recovery is lacking. Minimal research exists on the plant community trajectory of these mechanically disturbed sites. We studied the 32-Fire located east of Chico, CA. A fire line approximately 0.5 km long ranging in width from 6–12.2 m was created by a bulldozer. To assess plant recovery, we established plots in three pre-fire vegetation types: California Black Oak (Quercus kelloggii Newb.), Manzanita (Arctostaphylos manzanita Parry), and Wedgeleaf Ceanothus (Ceanothus cuneatus [Hook.] Nutt.) within three disturbance levels: burned, unburned (reference), and disturbed dozer line. Sites were sampled in 2018 (six-months post-fire) and in 2019 (18-months post-fire). In 2019, dozer line sites in the Manzanita and Wedgeleaf Ceanothus vegetation types did not have the dominant species found in similar unburned or burned sites. Across all vegetation types, dozer line sites had significantly higher average percent non-native species cover, compared with respective burned (P < 0.001, 95% C.I. = 33.2, 64.8) and unburned areas (P < 0.001, 95% C.I. = -77.2, -45.5). While unburned Wedgeleaf sites average non-native cover was 11% (SD = 9) in 2018 and 20% (SD = 5) in 2019, Wedgeleaf dozer line sites average non-native cover remained high between survey years at approximately 85%. Manzanita dozer line sites had average nonnative cover of 76% (SD = 16) and 57% (SD = 25) in 2018 and 2019, respectively, while unburned Manzanita had 9% (SD = 9) and 16% (SD = 16). Manzanita and Wedgeleaf Ceanothus species present on the study site are obligate seeders. Since neither species survived the implementation of the dozer line and no new recruitment of these species was observed, future recruitment of obligate seeders in these areas is unlikely. This suggests that dozer line sites with obligate seeders as dominant or co-dominant species are at risk of type conversion from native chaparral to annual grasslands dominated by non-native species.

Crowley's Ridge—Mixed Mesophytic Forests in Northeastern Arkansas

Crowley's Ridge is a low, narrow, eroded ridge that rises above the uniformly flat alluvial floodplain in the northeastern quadrat of Arkansas. The ridge is geologically unique because it consists largely of wind-blown soil (loess) deposited during the late Pleistocene. During June 2008, quantitative data on the composition and structure of all strata of forest vegetation were collected from ten 0.1 ha plots at two general localities on the southern portion of Crowley's Ridge. Acer saccharum (sugar maple) was the leading dominant in the large/ medium-sized tree stratum, followed by Quercus rubra (northern red oak), Q. velutina (black oak) and Q. stellata (post oak), all with importance value indices > 10. Other species present included Carya alba (mockernut hickory), Fraxinus americana (white ash), Fagus grandifolia (American beech), and Liriodendron tulipifera (tulip-tree). Except for post oak, these trees tend to be characteristic of the classic Mixed Mesophytic Forest Region of the southeastern United States. In six of the 10 plots, the combined importance values of species typically associated with mixed mesophytic forests represented 84% to 100% of the large/ medium-sized tree stratum. Twenty-three different species were recorded in this stratum, a level of diversity that is comparable to a mixed mesophytic forest. As such, the data presented herein indicate that at least some forests on Crowley's Ridge apparently represent the westernmost examples of this forest type.