Treesearch

Per- and polyfluoroalkyl substances (PFAS) are emerging contaminants, and many chemical adsorbents have recently been utilized for their removal. In this study, we synthesized a quaternary amine-modified (QA-CNF/DAC) composite aerogel by simultaneous cross-linking and amination of two most abundant natural polymers: cellulose nanofiber (CNF) and deacetylated chitin (DAC). The characterization results confirmed successful modification of aerogel by yielding a high surface area and quaternized amine content of 64.5 m2/g and 0.598 mmol/g, respectively. The aerogel exhibited high adsorption...

The objective of this research was to assess the potential of cellulose nanocrystals (CNCs) at laboratory scale within paving materials that make use of bituminous binders. Brittleness potential as measured by AASHTO T401 protocols was the primary evaluation mechanism where unconditioned, laboratory-conditioned, and field-aged materials were assessed. The investigation was divided into two components, neither of which are prevalent in literature or practice. The first evaluated CNCs within traditional dense graded asphalt mixed at temperatures on the order of 160°C and the second evaluated...

Successive catastrophic wildfire seasons in western North America have escalated the urgency around reducing fire risk to communities and ecosystems. In historically frequent-fire forests, fuel buildup as a result of fire exclusion is contributing to increased fire severity. The probability of high-severity fire can be reduced by active forest management that reduces fuels, prompting federal and state agencies to commit significant resources to increase the pace and scale of fuel reduction treatments. However, lower severity areas of wildfires also have the potential to act as “treatments,”...

Using mark-resight data, we investigated fidelity to territory and mate as well as breeding dispersal rates and the causes and consequences of breeding dispersal in a 20-year study of American goshawks (Astur atricapillus) in Arizona, USA. Generalized Additive Mixed Models were used to identify the relative contributions of four prominent explanatory variables (eggs laid, nest failed, nest successful, mate loss) and 21 individual and environmental variables in a machine learning Conditional Inference Forest to predict breeding dispersal. Ninety-five percent of males and 92% of females...

In Idaho, the Boise Basin, Deception Creek¸ and Priest River Experimental Forests (EFs) were established in 1911 and 1933 to facilitate long-term scientific research on multiple aspects related to forest management and ecology. Nestled within them are the Canyon Creek, Montford Creek, Bannock Creek, and Wellner Cliffs Research Natural Areas established in 1937, 1970, and 2004 to serve as reference areas for research, education, and monitoring of intensive management actions. Collectively, this network has advanced our knowledge on the species, distributions, and ecology of lichens,...

Root diseases are a major cause of conifer damage in forests of western North America. Two major root diseases in the region, which are caused by native pathogens, are laminated root rot (LRR) disease of Douglas-fir (Pseudotsuga menziesii) caused by Coniferiporia sulphurascens (Agne et al. 2018; Lockman and Kearns 2016; Thies and Sturrock, 1995), and black stain root disease (BSRD) caused by three fungal pathogens: Leptographium wageneri on single-leaf pinyon pine (Pinus monophylla) and pinyon pine (P. edulis), L. ponderosum on ponderosa pine (P. ponderosa) and Jeffrey pine (P. jeffreyi),...

Western white pine (WWP; Pinus monticola) is a keystone species in temperate, moist forests of western North America, where it displays adaptation to a range of climates and resilience to native root diseases (e.g., Harvey et al. 2008). Since Cronartium ribicola, the cause of white pine blister rust (WPBR), was introduced to North America in the early 1900s, WPBR has become well established and caused a dramatic reduction of WWP across its range (e.g., Neuenschwander et al. 1999; Harvey et al. 2008). Over recent decades, casual observations have indicated that WPBR incidence rates may be...

This report is aimed toward improving general awareness of various types of Armillaria samples and recommended survey practices to obtain collections for isolation/culture, DNA-based identification, and/or future studies. High-quality samples yield a higher success rate for DNA-based identification and allow isolation in the laboratory to obtain pure, living Armillaria cultures that can be archived for long-term storage for use in future research projects. In root disease surveys, samples of pathogenic Armillaria are frequently obtained from trees showing symptoms of disease, such as...

Although Armillaria has been previously surveyed in several western states of the USA, little definitive information on Armillaria species distribution in California has been provided in the last 20 years (e.g., Baumgartner and Rizzo 2001). Furthermore, it is well established that climate and climate change influence the distribution of Armillaria species that cause Armillaria root disease, which is a major cause of losses in forest growth and productivity (e.g., Lockman and Kearns 2016; Kim et al. 2021, 2022). This paper details recent progress towards identifying Armillaria for subsequent...

Altered fire regimes and post‐fire tree regeneration failures have the potential to drive forest cover losses throughout western North America, but management practices such as active reforestation may help address these challenges. Planting of nursery‐grown tree seedlings currently accounts for the majority of active reforestation in the western United States. Direct tree seeding—an alternative approach that involves dispersing seeds into a project site—is rare but has the potential to supplement planting and increase the pace and scale of reforestation activities, particularly where...