Treesearch

Georgia’s 24.4 million acres of forest are a diverse mix of hardwood and softwood tree species typical of the South. Hardwood forests account for 54.5 percent of the forested area (which includes 1.3 percent in nonstocked) versus 45.5 percent for softwood types. Georgia’s forest resources are considerable and slightly decreasing from 2014 in terms of the number of trees ≥1.0 inch diameter at breast height. The rate at which the State gained forest land acreage from converted agricultural land increased until 2012 and then decreased slightly from 59.5 thousand acres to 34.9 thousand acres....

Background. Sequestration of carbon on forest land is a common and practical component within many climate action plans developed by state or municipal governments. Initial planning often identifies the general magnitude of sequestration expected given the scope of the project. Because age plays a key role in forest carbon dynamics, we summarize both the carbon stock and accumulation rates in live trees by age class and region, allowing managers and policymakers to assess the influence of forest age class structure on forest carbon storage as represented in current inventories. State-level...

Oaks (Quercus spp.) are masting species exhibiting highly variable and synchronized acorn production.We investigated the hypothesis that periodical cicadas (Magicada spp.), well known to have strong effects on the ecosystems in which they occur, affect acorn production of oaks through their xylemfeeding habits as nymphs, the oviposition damage they inflict as adults during emergences, or the nutrient pulse resulting from the decomposition of their bodies following breeding. We found negative effects on acorn production during emergence years and the year following emergences and enhanced...

Following life-cycle assessment (LCA) methodology, this study presents a state-level estimation of embodied carbon of wood products harvested in 2019 from California and subsequently processed, manufactured, transported, used, and disposed at the end-of-life (EoL). In a conventional static approach to LCA, all GHG emissions were aggregated and considered to occur at year 0 of the given time horizon (500 years in this study) and used a static characterization factor (CF). In dynamic LCA, GHG emissions occurring in different years were considered, and their global warming impact (GWI) was...

The vexing error of excess variance in measurements of nanoparticle size distributions degrades accuracy in applications ranging from quality control of nanoparticle products to hazard assessment of nanoplastic byproducts. The particular importance of lipid nanoparticles for vaccine and medicine delivery motivates this Letter to the Editor, which concerns a publication 1 in ACS Nan and also presents original research. In ref 1, the benchmark measurements of a nanoparticle standard manifest large errors of the size distribution that contradict the claim of validation. In subsequent applicati...

Nevada lies in one of the driest parts of North America. The region has long grappled with droughts and also with extended periods in which the already dry climate aridified for decades or centuries. Here we place Nevada’s most recent statewide drought (2020 – present) in the context of historical, archaeological and paleoclimate records dating back through the Mid-Holocene. The current drought is distinct from historical droughts that impacted the state in the 1930s, 1950s, and 1970’s and 1980s. It is notably warmer than droughts of the 20th century and more spatially extensive than any...

In subalpine forests of the western United States, wildfires are becoming more frequent, severe, and widespread. In response, land management agencies are intensifying their efforts to reduce fire risk and severity, mitigate economic losses, and restore burned areas. These efforts, which include prefire tree removal, and postfire clearcutting, salvage logging, and planting, have varying impacts on wildlife. Sensitive species like fisher, spotted owl, and Canada lynx depend on structurally complex mature forests, and their habitats are often disturbed by forest management and by wildfire....

InSTREAM is a simulation model designed to support river management decisions. InSTREAM 7 is a major revision of the individual-based stream trout model we developed and have used for over 20 years. This user manual provides background information on inSTREAM and its purposes, a complete description of the model formulation, a software guide, and guidance on applying the model. InSTREAM is designed to predict how stream trout populations respond to habitat alteration including altered flow, temperature, and turbidity regimes and changes in channel morphology. The model represents individual...

We examine the interrelationships of national forest timber bid and log export prices for Douglas-fir (Region 6) in 2003–2021 and loblolly pine (Region 8) using time-series stationarity and bounds-testing approaches. The analysis shows the difference in time series properties across different geographies and time scales. Bid prices for these dominant species of timber in each of two Forest Service regions are found to be stationary, while log export prices for those same species appear to be non-stationary. Bounds testing conducted with autoregressive distributed lag modeling methods...

Subalpine forests in western North America are threatened by rapid climate change, increased activity by endemic and exotic insects and diseases, and changing wildfire regimes. The interactive effects of these stressors have resulted in pronounced population declines in many subalpine tree species; however, a systematic assessment of the status and trends of subalpine forests is lacking. Subalpine fir (Abies lasiocarpa) is a widespread species across the western United States, with documented population declines in many parts of its distribution. Here we use subalpine fir as an initial...