Treesearch

Great Basin bristlecone pine (Pinus longaeva), one of two species of bristlecone pine, the other being Rocky Mountain bristlecone pine (P. aristata), is endemic to the high Great Basin mountains in eastern California, Nevada, and Utah. It is the upper treeline forest tree in this region, found mostly between 2900 and 3600 m. The primary goal of this project was to generate a reference genome sequence for P. longaeva that, among its many possible applications, will serve as an important genetic resource to better understand the genetic mechanisms underlying its extreme longevity and its...

Fire is a significant disturbance agent, impacting forest structure and composition. In fire-adapted forests, fire can foster biodiversity by resetting successional processes and increasing habitat heterogeneity. However, fire suppression practices have altered historical fire regimes and left fire-adapted ecosystems largely unburned and the use of unburned forests by post-fire habitat specialists is understudied. Picoides arcticus (Black-backed Woodpecker) is a post-fire specialist that thrives in recently burned coniferous forests by exploiting heterogeneous patches of live and dead...

Juglans cinerea L. (2n = 16), commonly known as butternut, is a diploid species native to the eastern forests of the United States and Canada. It plays a crucial ecological role as a food source for wildlife and is traditionally used as a medicine by tribal communities. Butternut populations have severely declined over 50 years due to butternut canker disease (BCD). The ability of butternut to hybridize with Japanese walnut, which exhibits resistance to BCD, complicates hybrid identification based on morphological traits alone. In this study, we assembled the chloroplast genome of butternut...

Butternut (Juglans cinerea L.) is a rapidly declining tree species threatened by Ophiognomonia clavigignenti-juglandacearum (Oc-j), the causal agent of butternut canker. The introduction of Japanese walnut (Juglans ailantifolia Carrière), which hybridizes with butternut and exhibits greater resistance to the disease, presents both a conservation challenge and a potential avenue for genetic improvement. Identifying non-admixed butternuts is critical for conservation efforts and breeding programs aimed at preserving the species’ genetic integrity while exploring resistance strategies....

The environmental suitability of a particular organism is often a combination of local climatic factors, resource competition intensity, as well as pathogen and predator pressure. Pathogen pressure, or host resistance, is particularly important in host species severely impacted by disease. Variations in heritable pathogen resistance can lead to differences in apparent habitat suitability of resistant or susceptible subpopulations. In the case of the butternut tree (Juglans cinerea), habitat suitability is limited by genetic resistance to the non-native butternut canker disease (BCD) in...

Tree of heaven [ Ailanthus altissima (Mill.) Swingle] is an invasive tree that inhibits regeneration of forests. Management of forests invaded by A. altissima often includes chemically treating it and leaving dead boles behind. Verticillium wilt ( Verticillium nonalfalfae ) infects some populations of A. altissima , leading to localized mortality. Areas with population-wide A. altissima mortality may increase as this disease spreads or is used as a biocontrol agent. Ailanthus altissima has documented allelopathic compounds; stems left to decompose may result in soil legacy effects that...

The northern spotted owl (Strix occidentalis caurina) continues to decline across its range, threatened by habitat disturbances and invasive barred owls (Strix varia). We conducted a range‐wide spotted owl occupancy assessment using 2.1 million h of passive acoustic recordings from 4081 survey stations within 1027 randomly selected 5‐km 2 hexagons across six physiographic regions. Applying multistate occupancy models, we estimated probabilities of landscape use (by at least one northern spotted owl) and pair occupancy (occupied by both a male and a female), while accounting for imperfect...

Stress from low light availability and flooding can reduce photosynthesis and growth rates of trees, contributing to possible regeneration challenges in bottomland hardwood forests. This study investigated the photosynthetic light responses of pin oak (Quercus palustris Muenchh.) and swamp white oak (Quercus bicolor Willd.) seedlings growing in two light environments and across a hydrological gradient. Our findings revealed that neither light environment nor soil moisture availability had a significant impact on leaf mass per area, light compensation point, dark respiration rate, or...

Federal and state forest managers consider the effects of forest management, including no action, on carbon storage because of concerns of increasing atmospheric carbon dioxide (CO2) and other greenhouse gases that contribute to global warming. Most CO2 emissions in the United States result from burning fossil fuels. Forests represent a large store of carbon, but individual stands can absorb or emit substantial amounts of CO2 to the atmosphere over durations as short as a decade. Currently, wildland forests (those outside of urban zones) in the United States are a net sink of carbon,...

Pollution and deposition of sediments in rivers and streams are critical environmental, ecological, navigational, and recreational concerns. While several well‐known watershed models such as SWAT (Soil and Water Assessment Tool) and HSPF (Hydrological Simulation Program‐FORTRAN) are applied to predict sediment concentrations and loads in rivers and streams, their application requires the acquisition of a large amount of climatic, GIS, land use, and watershed input data, which is very time‐consuming and cost‐prohibitive. This study developed a copula‐based regression method to predict...