Treesearch

We revisit the research legacy of J.R. Blais and re-evaluate his contributions to spruce budworm—forest dynamics in light of a century of research, 1924–2025. We trace the evolution of scientific thought on outbreak ecology and reassess Blais’ foundational insights using contemporary data and methods. Blais’ alignment with a bottom-up, host-driven outbreak paradigm—centered on forest composition and epicentric spread—anticipated many findings now supported by modern research. Re-analysis of Blais’ historical outbreak maps (1802–1940) reveals a longitudinal gradient in outbreak frequency...

Urbanisation has led to increasing homogenization of plant communities across cities. However, it is unclear whether these patterns extend to cosmopolitan plant species at the genetic level. We examined genome‐wide genetic patterns in six widespread plant species (three Poaceae and three Asteraceae) across five cities in the USA (Boston, Baltimore, Minneapolis‐St. Paul, Phoenix, and Los Angeles) using reduced‐representation sequencing. We assessed genetic structure, differentiation, and patterns of isolation by distance (IBD) and environment (IBE) to determine if species were genetically...

Turnover in species composition often lags behind the pace of climate change, resulting in mismatches between climate and communities. However, the impact of these community‐climate disequilibria on ecosystem functions is rarely considered, and current methods for measuring disequilibria assume that species ranges were, until recently, in equilibrium with climate. Here, we develop a simple theoretical model to address both of these problems by linking community‐climate disequilibrium with ecosystem functioning. We show how disequilibrium can impair functioning in the near‐term even when...

For the past 20 years, approximately twice as many trees were removed annually from urban areas in the USA as were harvested annually from the US National Forest System. Yet, most of this wood is treated as waste instead of as a valuable resource to generate economic growth and sustainable cities. Residential landowners are key actors in the establishment of local urban wood economies as both sources of material and users of urban wood products, yet they remain a difficult to reach group compared with others, such as tree care companies, mill operators, and public landowners.We analyze a...

Successful landscape planning projects often incorporate input from local community members who live and work in the project area. Most people need to be able to see what a proposed change might look like; words are not enough. Images can provide a useful starting point for discussion among community members and planners, but community values and goals can be time-consuming to subsequently incorporate into draft visualizations and plans. Even when landscape architects can render visualizations for communities to use in planning, this process often requires meeting with stakeholders,...

New models quantifying tree volume, biomass, and carbon have recently been implemented across the USA, termed the National-Scale Volume and Biomass (NSVB) framework. Little research has been done to quantify the implications of these new models on the standing dead tree (SDT) carbon pool, which occupies a substantial portion of the nation’s total forest ecosystem carbon stocks. This project compared predictions of carbon stocks in SDTs using the previous estimation approach (the Component Ratio Method) and NSVB using the most recent FIA data collected across the conterminous USA. Equivalenc...

This indicator provides information on the number and distribution of forest-associated species and infraspecies (e.g., subspecies, varieties) at risk of losing genetic variation across their geographic range. Comparing current geographic distributions with historical distributions is the basis for identifying the species and infraspecies whose range has contracted significantly (based on per-State presence and absence). Human activities, like land use conversions, climate change, the alteration of native habitats, the introduction of exotic species, and direct exploitation, are acceleratin...

This summary report provides an overview of the current conditions, changing trends, issues, and threats to statewide forest resources based on findings from the 2018 inventory of New Jersey’s forests. New Jersey’s forests report an estimated 1.9 million acres of forest land and 89 tree species. Forest land is dominated by maples in the north and pitch pine in the south. The volume of growing stock on timberland currently totals 3.3 billion cubic feet. Average annual mortality of sound volume of live trees on forest land has remained relatively stable since 2013 and currently totals 54.7...

The boreal forests of Eurasia form the largest contiguous terrestrial biome in the world, providing numerous ecosystem functions and services for human societies. Temperatures are increasing most rapidly in high northern latitudes, altering tree growth and competition dynamics, and modifying disturbance regimes. The effect of these cumulative changes on the ecosystem functions provided by boreal forests is difficult to predict. We used the process-based LANDIS-II forest landscape model to evaluate how climate change and timber harvesting will interact to alter the production of ecosystem...

Disturbance creates structural legacies that are important drivers of functional and compositional stabilities in forested ecosystems. We used an experimental ice storm disturbance to evaluate effects of disturbance severity on structural legacies and their functional consequences. We evaluated canopy structural characteristics (height, density, openness, and complexity) before and after disturbance using data from terrestrial LiDAR. We compared trajectories of structural characteristics and functional outcomes (composition, mortality, and productivity) among treatments and relative to...