Treesearch

Climate change-triggered forest die-off is an increasing threat to global forests and carbon sequestration but remains extremely challenging to predict. Tree growth resilience metrics have been proposed as measurable proxies of tree susceptibility to mortality. However, it remains unclear whether tree growth resilience can improve predictions of stand-level mortality. Here, we use an extensive tree-ring dataset collected at ~3000 permanent forest inventory plots, spanning 13 dominant species across the US Mountain West, where forests have experienced strong drought and extensive die-off...

Horizontal wood diaphragm systems, whether decked with conventional or mass timber panels, transfer wind and seismic loads to vertical elements of the lateral force-resisting system, in flexible, rigid, or semirigid ways. Characterizing and calculating the resulting diaphragm deflections will help determine the distribution of forces to critically loaded components and a significant portion of lateral building translations and rotations. Deflection equations for sheathed wood structural panel (WSP) diaphragms are well established in US design standards in a four-term expression that models...

To further enhance the performance of wood products, improved tools are needed to study in situ cellular scale phenomena like mechanical deformations and moisture swelling. Micro-X-ray computed tomography (µXCT) using brilliant synchrotron light sources now has the spatial and temporal resolution for real-time visualization of phenomena in three-dimensional cellular structures. However, the tradeoff for speed includes the loss of intensity contrast between different types of materials within the imaged structure, such as cell wall and air in wood. This loss of contrast prevents traditional...

This Editorial provides summaries and an overview of research and review articles published in the Sensors journal, volumes 21 (2021), 22 (2022), and 23 (2023), within the biomedical Special Issue “Portable Electronic-Nose Devices for Noninvasive Early Disease Detection”, which focused on recent sensors, biosensors, and clinical instruments developed for noninvasive early detection and diagnosis of human and animal diseases. The ten articles published in this Special Issue provide new information associated with recent electronic-nose (e-nose) and related volatile organic compound (VOC)-det...

In California forests that have evolved with frequent fire, very large and severe modern wildfires can put ecological trajectories on a path of departure from reference or desired conditions. On the other hand, such fires may also advance recovery trajectories on parts of a burned landscape. It is important for land managers to understand and explain how postfire interventions may advance restoration and adaptation goals in different areas. This report advances a sciencebased framework to guide interventions for these situations. Targeted interventions to restore desired conditions and...

The caddisfly assemblages of Finch Creek, a small woodland stream in northern Lower Michigan, were sampled along its entire continuum during May, June, July, and September 2021–2022 using ultraviolet blacklight traps. A total of 98 species representing 15 families and 49 genera were collected, including two species [Lepidostoma prominens (Banks) and L. sommermanae (Ross)] not previously reported from Michigan, and several others either not previously found in the Lower Peninsula or not reported from the state for >70 years. A non-metric multidimensional scaling ordination determined...

Restoration efforts are underway in dry conifer forests across the western United States to increase their resilience to wildfire and other disturbances. Because such treatments typically decrease overstory density and homogeneity, they can also drive changes in the understory plant community. Past studies of post-treatment changes in understories have found variable results over short time frames and across regions, highlighting the need to study longer-term, region-specific responses. We investigated whether mechanical restoration treatments benefited understory plants in dry conifer...

Background: Planting tree seedlings may help promote forest recovery after extensive high-severity wildfire. We evaluated the influence of growing environment characteristics on the performance of seedlings planted in the 2016 Cold Springs Fire, Colorado, USA. In 2021, four growing seasons after planting, we measured survival, height, and 2021 height growth for 300 ponderosa pine, limber pine, and Douglas-fir seedlings permanently marked along “stake rows.” For each seedling, we also recorded one site-level growing environment characteristic, aspect, and two microsite-level characteristics,...

Symbiotic nitrogen fixation (SNF) is a critical mechanism of ecosystem recovery, and in forests of the eastern United States, the most common tree species that supports SNF is black locust (Robinia pseudoacacia L.). Despite its prevalence, black locust’s fixation strategy - whether it maintains fixation at a constant rate (obligate fixation) or reduces its fixation rate (facultative fixation) - is unknown. Here, we examined how nitrogen and light control SNF by black locust, by growing seedlings under two nitrogen levels and across four levels of light. Seedlings were harvested after 12...

Urban centers are places with a high human population concentration, and they can pose social, economic, and environmental challenges. These challenges are accentuated by the increased use of available open space for housing and industrial expansion, leading to elevated energy consumption, increased pollution, higher carbon emissions, and, consequently, adverse effects on human health. Many of these issues also contribute to the acceleration of climate change. There are several ways to decrease these problems through the expansion of greenspaces that conserve biodiversity, decrease air...