Treesearch

Wildfires in the southwestern United States are increasingly frequent and severe, but whether these trends exceed historical norms remains contested. Here we combine dendroecological records, satellite-derived burn severity, and field-measured tree mortality to compare historical (1700-1880) and contemporary (1985-2020) fire regimes at tree-ring fire-scar sites in Arizona and New Mexico. We found that contemporary fire frequency, including recent, record fire years, is still <20% of historical levels. Since 1985, the fire return interval averages 58.8 years, compared to 11.4 years before...

Uncrewed aerial system (UAS) structure from motion (SfM) monitoring strategies for individual trees has rapidly expanded in the early 21st century. It has become common for studies to report accuracies for individual tree heights and DBH, along with stand density metrics. This study evaluates individual tree detection and stand basal area accuracy and precision in five ponderosa pine sites against the range of SfM parameters in the Agisoft Metashape, Pix4DMapper, and OpenDroneMap algorithms. The study is designed to frame UAS-SfM individual tree monitoring accuracy in the context of data...

Sagebrush ecosystems across the western U.S. are in decline due to numerous threats, including expansion of coniferous woodlands and forests. The interagency Sagebrush Conservation Design effort recently quantified sagebrush ecological integrity (SEI) to map remaining core sagebrush areas (relatively intact and functional sagebrush ecosystems) and understand spatial and temporal patterns of change relative to primary threats. Recent work has identified conifer expansion as the second leading cause of de- cline in sagebrush ecological integrity biome wide. Here, we sought to create a...

Recent studies have shown numerous Fusarium spp. are associated with symptomatic conifer seedlings in both bareroot and container nursery systems. Some of these species have been found pathogenic to conifer seedlings (e.g., F. avenaceum, F. commune, F. oxysporum, F. solani, and F. verticillioides), but the mechanisms and shared evolutionary history of these conifer pathogenic species have not been well studied in these pathosystems. We compared whole genomes of 17 Fusarium spp. associated with conifer seedlings to elucidate putative shared pathogenicity/virulence gene profiles presumably...

Conservation of species’ mobility and ecological integrity is necessary for the productivity of the sagebrush biome in the western United States. Building on the recently developed Sagebrush Conservation Design (SCD) that mapped sagebrush ecological integrity (SEI) - defined as the higher cover of sagebrush and perennial grass and reduced threats due to invasive annual grass, tree encroachment, and human disturbance - we modeled the structural connectivity of sagebrush ecosystems to better incorporate the role of landscape-level processes into assessments of integrity. Because integrity...

Across the western United States, large, severe wildfires in montane forests are creating treeless patches that can fail to reforest naturally due to a lack of seed sources and a warming climate. Nursery-grown tree seedlings are commonly planted by land managers into these areas to promote forest recovery and resilience, but uncertainty exists about what influences their survival across the landscape. We obtained survival monitoring data that had been collected one growing season after planting for 5656 tree seedlings, which were distributed across nine montane wildfires and four National...

This poster highlights wildflowers (forbs) common in sagebrush vegetation of the Great Basin. These wildflowers support countless wildlife species, including some species only found in sagebrush ecosystems, such as the greater sage-grouse. Many forb species (including most featured here) are highly valued and used for food, medicine and ceremony by the many Indigenous peoples of the Great Basin. There are hundreds of forb species in sagebrush ecosystems, all with their own unique characteristics. The 31 species on this poster highlight common species potentially useful in restoration....

Open burning is commonly used to dispose of piles of forest residues generated by forest management activities; however, this method is associated with smoke emissions and damage to forest soil. Air curtain burners (ACB), such as the Firebox (FB) and CharBoss® (CB), offer an alternative to open burning. This study evaluated the performance of FB for biomass disposal and CB for biomass disposal and biochar production with the objective of quantifying the benefits and limitations of each machine. Ponderosa pine biomass obtained from harvesting after a wildfire event and freshly cut wood from...

For millennia, wildfire has helped shape the sagebrush biome of the western United States. Over recent decades, historical fire regimes have been altered by several factors, including contemporary climate and fuel conditions, leading to the loss or degradation of hundreds of thousands of hectares (ha) of sagebrush each year. In response to wildfire threats, extensive fuel treatment investments are proposed across the region. To help inform strategic and cost-effective investments, we conducted a quantitative assessment of wildfire risk for the sagebrush biome. We used a geospatial fire...

This study utilizes Automatic Dependent Surveillance–Broadcast (ADS-B) data sourced by the OpenSky Network to curate a dataset aimed at enhancing the precision of aerial suppressant drop predictions in wildland firefighting. By amalgamating ADS-B data with Automated Telemetry Unit (ATU) drop information, this research constructs a reliable base for analyzing the spatial aspects of aerial firefighting operations. Using sequential machine learning models, specifically Long Short-Term Memory (LSTM) networks and 1D Convolutional Neural Networks (1DCNN), the study interprets complex flight...