Treesearch

Releasing several ecotypes or species of biological control agent is common in many biological control programs. However, the consequences of hybridization for fitness and host use of the resulting hybrids are difficult to predict, especially for hybrids between more than two species and with varying levels of introgression. Hybridization of biocontrol agents may increase or decrease fitness, with consequences for control efficacy. Additionally, hybridization may lead to changes in host use patterns that may put non-target host species at increased risk. We collected genomic data to...

Although recent large wildfires in California forests are well publicized in media and scientific literature, their cumulative effects on forest structure and implications for forest resilience remain poorly understood. In this study, we evaluated spatial patterns of burn severity for 18 exceptionally large fires and compared their cumulative impacts to the hundreds of smaller fires that have burned across California forests in recent decades. We used a burn severity atlas for over 1,800 fires that burned in predominantly conifer forests between 1985 and 2020 and calculated landscape...

Remote sensing is widely used to detect forest disturbances (e.g., wildfires, harvest, or outbreaks of pathogens or insects) over spatiotemporal scales that are infeasible to capture with field surveys. To understand forest ecosystem dynamics and the ecological role of human and natural disturbances, researchers and managers would like to characterize spatiotemporal patterns of several types of disturbance. Recent advances include the development and testing of algorithms to automatically detect and attribute an array of disturbance types across large forest landscapes from remotely sensed...

The authors are a team of fire whirl researchers who have been actively studying whirls and large-scale wildland fires by directly observing them through fire-fighting efforts and applying theory, scale modeling, and numerical simulations in fire research. This multidisciplinary research-background team previously conducted scale model experiments to reconstruct hazardous large-scale fires in the laboratory, then conducted numerical simulations and developed fundamental theories to translate these findings into a basic understanding of combustion science and fluid dynamics. This article, a...

In the 2020 fire season, the fire management community developed and tested a wide range of new practices to meet challenges posed by the coronavirus pandemic. To better understand the effectiveness of different innovations and which should be considered for more permanent use, we surveyed Interagency Hotshot Crew (IHC) superintendents in January 2021. We focused on identifying innovations that, regardless of COVID-19, the IHCs would want to keep and why, as well as those that proved problematic. The survey focused on paperwork, briefings, and fire camp and incident command post setup....

Now over twenty years into the 21st century, it is suggested that we are entering a new era of wilderness visitor use management (VUM). Yet, we lack a recent review of the literature assessing the latest research trends to advance wilderness VUM in a meaningful way. Accordingly, this research serves as both a review of the last twenty years of U.S. wilderness VUM research and a launching point into the next era. Our assessment adds to several previous benchmarks that demonstrate the progress of wilderness VUM research. This review evaluates trends in methodologies and themes of inquiry...

Wildfires are increasing in scale and impact on the landscape, altering large amounts of wildlife habitat and forest ecosystems. The reduction of fuels through forest management is considered a primary way to reduce the extent and severity of wildfires before they occur but may lead to a decrease in tree density prohibitive of some species’ habitat. Alternatively, management actions undertaken after a fire may speed the trajectory of burned areas back into quality habitat but may also impede this development if the wrong type of treatment is undertaken. Thus, information on how different...

Forest therapy is an emerging holistic health practice that uses multisensory immersive engagements in forest settings to achieve health and wellbeing outcomes. Many forest therapy engagements take place via slow walks along a trail to optimally experience the array of sensory phenomena afforded along the route, yet surprisingly few forest therapy studies to date have investigated the characteristics of forest sites and trails that give rise to healthful experiences. In this research, we employ a hybrid approach to understand the conditions and features that contribute to a good forest...

The physical structure of vegetation is thought to be closely related to ecosystem function, but little is known of its pertinence across geographic regions. Here, we used data from over three million trees in continental North America to evaluate structural diversity - the volumetric capacity and physical arrangement of biotic components in ecosystems - as a predictor of productivity. We show that structural diversity is a robust predictor of forest productivity and consistently outperforms the traditional measure - species diversity - across climate conditions in North America. Moreover,...

Precipitation is a key driver of primary production worldwide, but primary production does not always track year-to-year variation in precipitation linearly. Instead, plant responses to changes in precipitation may exhibit time lags, or legacies of past precipitation. Legacies can be driven by multiple mechanisms, including persistent changes in plant physiological and morphological traits and changes to the physical environment, such as plant access to soil water. We used three precipitation manipulation experiments in central Texas, USA to evaluate the magnitude, duration, and potential...