Noah Weidig

Trees and shrubs are expanding into historically open ecosystems across the globe, threatening ecological function and ecosystem services. Across much of the eastern U.S., increasing woody cover has been associated with ecological degradation of forest and savanna ecosystems, and more recently, heightened large wildfire risk. Understanding patterns in woody cover increases will be paramount for assessing potential ecological outcomes and developing region-specific management approaches. Using remotely sensed land-use and vegetation cover data, we quantified changes in woody cover between 2001 and 2021 across land-use types in the eastern U.S. to determine the relative contribution of forest infilling and land-use conversion to woody cover increases. Woody cover increased across a range of land-use types in the eastern U.S. including wetlands, pasturelands, and forests. Infilling of deciduous forests and encroachment in open land-use types such as pasturelands dominated the northeast. In contrast, high levels of land-use conversion from non-woody land-use types to forests along with increasing woody cover in wetlands dominated the southeast. Our findings suggest that increasing woody cover in the eastern U.S. likely reflects both intentional increases of woody cover by silviculture as well as unintentional increases tied to wetland woody encroachment and forest densification. Our findings highlight areas to target ecological impact assessments and management efforts. Further, we demonstrate a growing need to assess the potential impacts of expanding pine plantation area on forest ecology and changing wildfire risk.

The recent increase in large wildfires in the eastern United States makes it crucial to examine the subsequent risk to human life and property. In the eastern US, the wildland–urban interface (WUI), where wildfire risk is greatest, has expanded tremendously over the last three decades. Aims: This study aimed to understand how increasing wildfires in the eastern US are manifesting in the WUI. We quantified WUI growth and characterised large (>200 ha) wildfire regimes inside and outside the WUI at multiple spatial scales across the eastern US between 1986 and 2021. WUI wildfires in the eastern US comprised 45% of all large wildfires and 55% of the area burned, were on average 46% larger than non-WUI wildfires, and are becoming more frequent in spring. Most increases in wildfire number and area burned occurred outside of the WUI. The WUI plays an important role in large wildfire dynamics in the eastern US; however, increases in the number of large wildfires have occurred primarily outside the WUI. Our findings highlight important interactions between human development and large wildfire occurrence in the eastern US and should be used to direct future region-specific assessments of changing wildfire risk.

Large wildfires are increasing in the eastern United States; however, what factors are heightening large wildfire risk remains unclear. Increases in fuel loads from woody encroachment and canopy infilling have been associated with increasing wildfire risk in other US regions. Understanding if and where woody cover increases wildfire risk can help direct proactive fuels management. We characterize multi-scale changes in woody cover through time and assess the relationship between woody cover and large wildfire (>200 ha) occurrence in the eastern US between 1990 and 2020. We found a 37% increase in woody cover across the eastern US, with increases occurring in every ecoregion. The odds of large wildfire increased as woody cover increased in most central and southern ecoregions, where large wildfires were typically more likely in areas with high woody cover (70%–100% cover). Our findings suggest fuels management will be an important tool for reducing large wildfire risk.

Females of container-breeding mosquito species use visual and chemical cues to determine suitable habitats to oviposit their eggs. Female Culex mosquitoes oviposit single egg rafts containing hundreds of eggs on the surface of water in container habitats. In this project, the effects of water volume and nutrient concentration were studied using three semi-controlled field assays to determine the role these parameters play on female Culex mosquito oviposition preference. The results of this study suggest female Culex prefer to oviposit in larger volumes of water and higher concentrations of nutrients separately, but chose intermediate conditions when presented with a combination of these two variables, which follows the Goldilocks principle. This choice may provide their offspring with optimal conditions for development by reducing intraspecific competition, thereby maximizing the biological fitness of the ovipositing Culex females.

As urbanization continues, animals are increasingly compelled to navigate human-altered environments. Here we investigate wildlife use of stormwater sewer systems (SSS), a widespread, subterranean environment resulting from urbanization. We used camera traps to reveal how wildlife exploit subterranean pathways, shedding light on their presence within this anthropogenic context in Alachua County, Florida. From February to May 2023, we documented a total of 35 species of vertebrates within SSS, including amphibians, reptiles, and birds, although mammals dominated our sample. Raccoons and Southeastern Myotis accounted for more than half of all observations, signifying their prevalence and widespread presence within SSS. Our research offers a comprehensive exploration of vertebrate diversity within an unconventional urban habitat and provides valuable insights into the relationship between SSS and species utilization patterns. Ultimately, our research lays the groundwork for future studies and informs the development of ecologically conscientious urban planning strategies.

Large wildfires are increasing in the eastern United States, raising concern about the risk to human life and property within the wildland-urban interface (WUI), where development and vegetation intermingle. In this webinar, we will explore large wildfire patterns inside and outside the WUI and the factors driving these patterns over the past three decades in the eastern U.S. Although the WUI only covers 22% of this region by area, it plays a crucial role in large wildfire dynamics. We found that environmental factors—particularly higher woody cover and drier conditions—and, to a lesser extent, social factors, influence where wildfires occur in and near the WUI. Our findings highlight complex interactions between human development and large wildfire occurrence, as well as the need for proactive fuels management in the East.

Dr. Donovan will provide a summary of her lab's ongoing research investigations into changes in large (>200 ha) wildfire activity across multiple scales in the eastern U.S. and the interacting factors affecting wildfire risk. Specifically, we found shifting wildfire regime characteristics across south and central ecoregions in the east that include increasing wildfire number, size, and annual occurrence, along with changes in wildfire seasonality. Just under half of all wildfires burned within the wildland-urban interface (WUI), where the greatest risk to human life and property from wildfires exists. Increases in large wildfire are largely occurring outside the WUI, though these wildfires tend to be closer to the WUI than expected at random. We find factors such as suppression potential, weather conditions, and patterns in woody cover influence the WUI-wildfire dynamic, but relationships vary regionally. We also identified long-term increases in woody cover across eastern ecoregions, linking higher levels of woody cover to heightened wildfire risk in multiple locations. Further investigations have found that woody cover interactions with short-term drought strongly predict large wildfire occurrence across numerous eastern ecoregions. While further research into the drivers of changing large wildfire patterns is needed, we suggest the strategic application of fuels management along with the development of fire-resistant homes and buildings to enhance community resilience to wildfire in the east.

Wildfire risk is changing across the globe. We provide a summary of ongoing investigations into changes in large (>200 ha) wildfire activity across multiple scales in the eastern U.S. and the interacting factors affecting wildfire risk. We found shifting wildfire regime characteristics across south and central ecoregions in the east that include increasing wildfire number, size, and annual occurrence, along with changes in wildfire seasonality. Human ignitions started most wildfires in the eastern U.S., though in the Southern Coastal Plain, the majority of area burned was caused by naturally started wildfires. Just under half of all wildfires burned within the Wildland-Urban Interface (WUI), where the greatest risk to human life and property from wildfires exists. However, increasing trends in large wildfire are largely occurring outside the WUI. We find factors such as suppression potential, weather conditions, and fuels influence this dynamic. We also identified long-term increases in woody cover across eastern ecoregions, linking higher levels of woody cover to heightened wildfire risk in multiple locations. Further investigations find that climate-woody cover interactions strongly predict large wildfire occurrence across numerous eastern ecoregions. While further research into the drivers of changing large wildfire patterns is needed, we suggest the strategic application of fuels management along with the development of fire-resistant homes and buildings to enhance community resilience to wildfire.

Large wildfires are increasing in the eastern U.S., which contains the greatest amount of wildland-urban interface (WUI) compared to the rest of the country. Wildfires in and near the WUI pose the greatest risk to human life and property. However, the spatial relationship between large wildfires and the WUI in the eastern U.S., as well as which factors drive these patterns, remains unclear. Using large wildfire (>200 ha) data from 1991 and 2021, we (1) assessed the spatial relationships of large wildfires relative to the WUI and (2) modeled these relationships using a variety of social and environmental variables at multiple spatial scales. Specifically, we assessed wildfire WUI status (intersecting or outside the WUI), distance to WUI, and proportion of WUI area burned. We found that fewer large wildfires burned in the WUI compared to randomly selected locations within the study region. Wildfires that intersected the WUI burned either a very small or very large proportion of the WUI; however, wildfires outside the WUI burned closer to it than expected by chance. At the largest spatial scale, our global model containing weather, fuel, ignition, and suppression-related variables best explained the relationship between wildfires and the WUI. Overall, wildfires in the WUI burned in areas with higher woody cover, more suppression resources nearby, higher road density, lower precipitation, lower wind speed, and during times when suppression resources were more strained than wildfires outside the WUI. As wildfires burned a greater proportion of the WUI, these trends were heightened. Large wildfires that burned closer to the WUI had higher woody cover, higher road density, and lower fuel moisture. At the regional scale, significantly correlated factors driving these relationships varied among eastern ecoregions, suggesting regionally context-dependent wildfire risk. Our findings highlight the need for region-specific wildfire risk management and improved fire suppression planning.

Large wildfires are increasing in the eastern U.S., which contains the greatest amount of WUI compared to the rest of the country. Wildfires in and near the WUI pose the greatest risk to human life and property. However, the spatial relationship between large wildfires and the WUI in the eastern U.S., as well as which factors drive these patterns, remains unclear. Using large wildfire (>200 ha) data from 1991 and 2021, we (1) assessed the spatial relationships of large wildfires relative to the WUI and (2) modeled these relationships using a variety of social and environmental variables at multiple spatial scales. Specifically, we assessed wildfire WUI status (intersecting or outside the WUI), distance to WUI, and proportion of WUI area burned. We found that fewer wildfires burned in the WUI compared to a random distribution. Wildfires that intersected the WUI burned either a very small or very large proportion of the WUI; however, wildfires outside the WUI burned closer to it than expected at random. At the largest spatial scale, our global model containing weather, fuel, ignition, and suppression-related variables best explained the relationship between wildfires and the WUI. Overall, wildfires in the WUI burned in areas with higher woody cover, more suppression resources nearby, higher road density, lower precipitation, lower wind speed and during times when suppression resources were more strained than wildfires outside the WUI. Wildfires that burned a larger proportion of the WUI or burned closer to the WUI experienced similar trends compared to wildfires that burned a smaller proportion of the WUI or burned farther from the WUI. At the regional scale, factors driving these relationships varied among eastern ecoregions. Our findings highlight the need for region-specific wildfire risk management and improved fire suppression planning.

Large wildfires are increasing in the eastern U.S., which contains the greatest amount of WUI compared to the rest of the country. Wildfires in and near the WUI pose the greatest risk to human life and property. However, the spatial relationship between large wildfires and the WUI in the eastern U.S., as well as which factors drive these patterns, remains unclear. Using large wildfire (>200 ha) data from 1991 and 2021, we (1) assessed the spatial relationships of large wildfires relative to the WUI and (2) modeled these relationships using a variety of social and environmental variables at multiple spatial scales. Specifically, we assessed wildfire WUI status (intersecting or outside the WUI), distance to WUI, and proportion of WUI area burned. We found that fewer wildfires burned in the WUI compared to a random distribution. Wildfires that intersected the WUI burned either a very small or very large proportion of the WUI; however, wildfires outside the WUI burned closer to it than expected at random. At the largest spatial scale, our global model containing weather, fuel, ignition, and suppression-related variables best explained the relationship between wildfires and the WUI. Overall, wildfires in the WUI burned in areas with higher woody cover, more suppression resources nearby, higher road density, lower precipitation, lower wind speed and during times when suppression resources were more strained than wildfires outside the WUI. Wildfires that burned a larger proportion of the WUI or burned closer to the WUI experienced similar trends compared to wildfires that burned a smaller proportion of the WUI or burned farther from the WUI. At the regional scale, factors driving these relationships varied among eastern ecoregions. Our findings highlight the need for region-specific wildfire risk management and improved fire suppression planning.

Woody cover increases in historically open ecosystems are occurring across the globe, leading to ecosystem degradation and increased wildfire risk. Tree and shrub cover is increasing in the eastern United States, which historically was dominated by open forest ecosystems; however, it is still unclear whether recent woody cover increases are due to infilling, linked to ecosystem degradation due to fire suppression, or to land use changes such as conversion of croplands to commercial pine plantations. Understanding the nature of recent woody cover increases is essential for identifying and addressing potential risks to ecosystem function and human activities. Using remotely sensed data, we quantified woody cover changes from 2001 to 2021 across land use types and compared the relative contribution of infilling and land-use conversion to increasing woody cover trends. We found that although overall forest cover had decreased, remaining forests became denser, especially deciduous forests. This infilling contributed the majority of increasing woody cover on the landscape. However, the conversion of non-forested land-cover types to evergreen forests was also a significant contributor to increasing woody cover on the landscape, especially in the southern half of the region. Our findings suggest that forest infilling is the greatest contributor to increasing woody cover in the eastern U.S., suggesting the continued degradation of fire-dependent open forests in the eastern U.S.

Global change is altering ecosystem structure and function including natural disturbance processes like fire that can threaten human communities. We assess changes in large (greater than 200 ha) wildfire activity across southeastern U.S. ecoregions and highlight current lines of investigation for factors that are increasing wildfire risk. We found shifting wildfire regime characteristics across southeastern ecoregions that include increasing wildfire number, size, and annual occurrence, along with changes in wildfire seasonality. More than 25% of wildfires occurred within the wildland-urban interface (WUI), where wildlands meet human development, and thus can pose a heightened risk to communities. However, increases in wildfires in the WUI were not as substantial as those in other areas. Human ignitions started most wildfires in the southeastern U.S., though in the Southern Coastal Plain, the majority of area burned was caused by naturally started wildfires. We also found long-term increases in woody cover across southeastern ecoregions, which has been associated with increasing wildfire risk. While further investigation into the drivers of changing large wildfire patterns are needed, we suggest further application of fuels management and the promotion of fire resistant homes and buildings to enhance community resilience to wildfire.

Cogongrass (Imperata cylindrica) is a pervasive invasive plant species across the Gulf of Mexico region and listed as the seventh worst weed in the world. Negative impacts to Gulf Coast ecosystems include agricultural disturbances, increased fire risk, and drastic declines in native plant communities. Cogongrass can form near or full monoculture patches in optimal conditions, with rapid colonization following recent disturbance events like fire where it outcompetes native species. However, the effects of newly infested Cogongrass colonizations on individual established native plants are relatively unknown. We investigated the impacts of cogongrass invasion on three native re-sprouting shrub species (Beautyberry, Yaupon Holly, and Mayberry) following a recent fire. We assessed variability in native plant height, leaf area, stem count, and diameter in relation to Cogongrass presence and percent groundcover to determine the effects of Cogongrass on shrub regeneration following fire. In addition, we measured soil moisture content and canopy cover as covariates. We hypothesized that Cogongrass will negatively impact native plant regeneration post-fire. Interestingly, we found positive relationships between shrub regeneration and cogongrass density, opposite to our prediction. Cogongrass density and soil moisture also were significantly correlated. Our data provides important information on native plant resistance to cogongrass invasion and may provide useful information for early intervention management following fire.

This talk covers the fundamentals of using R Markdown to create reproducible workflows that seamlessly integrate code, results, and narrative. It will demonstrate how R Markdown enables efficient documentation and sharing of data analyses by combining R code with formatted text in a single document. Key topics include setting up R Markdown files, organizing content with chunks, generating dynamic reports in various formats, and best practices for maintaining reproducibility and clarity in data science projects.

Wildfires are increasing in the eastern United States. The wildland-urban interface (WUI), which occurs at the intersection between human development and wildland vegetative fuels, remains the focus for predicting and mitigating wildfire risk. Wildfires in the WUI require more resources to suppress, destroy more homes, and pose a greater threat to human life. The eastern U.S. contains a disproportionately large amount of the WUI compared to other parts of the country, making it crucial to characterize differences between WUI and non-WUI wildfire regime changes. We contrast spatial and temporal characteristics of WUI versus non-WUI wildfire regimes across Level III ecoregions in the eastern U.S. using decadal WUI maps from 1990 to 2020 combined with large wildfire perimeter data and ignition source data from 1986 to 2021. We found that a substantial proportion of wildfires occurred in the WUI (45%), even though the WUI only makes up 22% of the eastern U.S. by area. The number of wildfires, mean area burned, and total area burned increased both inside and outside the WUI in most ecoregions. The primary source of wildfire ignitions in the WUI was arson and, secondarily, natural causes (lightning). The results of this study highlight the increasing risk of large wildfires in the eastern U.S. and can be used to help support informed decision-making surrounding wildfire risk management in the region.

The recent increase in large wildfires in the eastern United States makes it crucial to examine the subsequent risk to human life and property. In the eastern US, the wildland–urban interface (WUI), where wildfire risk is greatest, has expanded tremendously over the last three decades. Aims: This study aimed to understand how increasing wildfires in the eastern US are manifesting in the WUI. We quantified WUI growth and characterised large (>200 ha) wildfire regimes inside and outside the WUI at multiple spatial scales across the eastern US between 1986 and 2021. WUI wildfires in the eastern US comprised 45% of all large wildfires and 55% of the area burned, were on average 46% larger than non-WUI wildfires, and are becoming more frequent in spring. Most increases in wildfire number and area burned occurred outside of the WUI. The WUI plays an important role in large wildfire dynamics in the eastern US; however, increases in the number of large wildfires have occurred primarily outside the WUI. Our findings highlight important interactions between human development and large wildfire occurrence in the eastern US and should be used to direct future region-specific assessments of changing wildfire risk.

Females of container-breeding mosquito species use visual and chemical cues to determine suitable habitats to oviposit their eggs. Female Culex mosquitoes oviposit single egg rafts containing hundreds of eggs on the surface of water in container habitats. In this project, the effects of water volume and nutrient concentration were studied using three semi-controlled field assays to determine the role these parameters play on female Culex mosquito oviposition preference. The results of this study suggest female Culex prefer to oviposit in larger volumes of water and higher concentrations of nutrients separately, but chose intermediate conditions when presented with a combination of these two variables, which follows the Goldilocks principle. This choice may provide their offspring with optimal conditions for development by reducing intraspecific competition, thereby maximizing the biological fitness of the ovipositing Culex females.

The recent increase in large wildfires in the eastern United States makes it crucial to examine the subsequent risk to human life and property. In the East, thewildland-urban interface (WUI), where wildfire risk is greatest, has expanded tremendously over the last three decades. In this thesis, we aimed to understand how increasing large wildfires in the East are manifesting in the WUI. Using large (≥200 ha) wildfire perimeters, we (1) assessed WUI growth and its relationship with large wildfire regime characteristics and (2) determined the spatial WUI-wildfire relationships and the social and environmental factors driving these patterns over the last three decades in the eastern US at multiple spatial scales. While the WUI only makes up 22% of the East, WUI wildfires comprised 45% of all large wildfires and 55% of the area burned, were on average 46% larger than non-WUI wildfires, and are becoming more frequent in spring. Most increases in wildfire activity occurred outside of the WUI. Additionally, large wildfires burn less often in the WUI and less of the WUI than expected at random; however, wildfires that burn outside of the WUI burn closer to the WUI than expected. Environmental factors and, to a lesser extent, social variables are important for predicting these WUI-wildfire relationships. Higher levels of woody cover, drier conditions, and strained federal suppression resources drove wildfire occurrence in and near the WUI. Our findings highlight important interactions between human development and large wildfire occurrence and the need for proactive fuels management in the East.

This Open Letter by Kalapodis and Sakkas presents a framework for enhancing the resilience of forests against the increasing wildfire issue in Europe by integrating Integrated Fire Management (IFM) and Closer-to-Nature Forest Management (CTNFM). The authors cover a wide array of topics concerning fire suppression, fuel management, wildfire preparedness, and forest resilience. While addressing the recent rise in both the frequency and intensity of wildfires in Europe is relevant, it is unclear whether this paper makes a significant contribution to this effort. A primary concern is that much of the language throughout the letter is unclear and requires numerous changes to improve the flow and readability of the manuscript. Additionally, this manuscript is rather long and winding making it difficult to follow. A key missing piece upon reading the paper is why the authors specifically choose to focus on these two approaches and why do they argue they need to be integrated? It is difficult to assess the validity for the paper since it is unclear what the justification is for the integration of the approaches. Overall, the current version requires substantial revision to clarify their arguments, reduce repetitive language, and improve of the general flow of the manuscript.

This study characterizes changes in woody vegetation cover across the eastern United States from 1990 to 2020 and evaluates its association with the occurrence of large wildfires (i.e., >200 ha (~494 acres)). Although woody encroachment and canopy infilling have been partially linked to increased wildfire risk in the western US and Great Plains, large-scale trends in eastern U.S. woody vegetation—and their potential influence on wildfire risk—remain less well understood.

As development continues to expand into fire-prone landscapes, the eastern United States is experiencing notable shifts in wildfire patterns. Weidig and colleagues analyzed four decades of wildfire records to examine how large wildfire dynamics have changed across eastern ecoregions, with a particular focus on the wildland-urban interface (WUI)–areas where homes and wildlands meet. The study assessed trends in wildfire size, frequency, and seasonality both within and outside the WUI, providing new insights into how changing land use and fire weather are reshaping fire regimes in this land-use type. The authors found that wildfire activity has increased across much of the eastern U.S., with the number of wildfires having grown over time–especially in the southeastern coastal plain. Nearly half of all recorded wildfires across the eastern U.S. occurred within the WUI, most of which occurred in the Central Appalachian region. While these WUI fires pose the greatest threat to human life and property, the most extensive fires typically occurred outside of developed areas. The southeastern coastal plain saw the most large wildfires occur outside the WUI, yet most wildfires within and outside the WUI in the region were human-caused. The timing of wildfires also shifted, with more fires occurring earlier and later in the year–indicating a lengthening fire season. These trends suggest that interactions among vegetation growth, human development, and changing weather conditions are driving more frequent and widespread wildfires in the eastern U.S. For fire managers in the southern region, this study supports the use of prescribed fire as a proactive tool for reducing fuel loads and mitigating wildfire risk near expanding communities. As fire seasons lengthen and weather windows for prescribed burning become less predictable, managers may need to adopt more flexible and adaptive approaches to maintain desired fire frequencies. Moreover, the finding that most wildfire ignitions in the southeast are human-caused underscores the value of cross-jurisdictional coordination and community outreach in the WUI to promote fire-adapted landscapes. Nevertheless, continued application of prescribed fire remains essential for sustaining ecosystem resilience and reducing the potential for catastrophic wildfires.

Woody vegetation has increased by 37% over the last 30 years in the eastern United States, fueling the rise in large wildfires. Texas and the Appalachian Mountains took the biggest hits.