Treesearch

Ecological theory predicts that consumers should be co-limited by resource quantity and quality, given widespread consumer-resource nutritional imbalances. We used 25 estimates of annual community secondary production (ACSP) of stream macroinvertebrates to assess the relative roles of basal resource quantity (leaf litter standing stock [LLSS]) and quality (% nitrogen and % phosphorus of leaf litter) in modulating patterns of production in forest streams. We also tested the effects of hypothesized indirect drivers (stream discharge and inorganic nutrient concentrations) on basal resource...

Community-based collaboration has been touted as an effective model for forest governance because it promotes democratized decision-making and stakeholder engagement to address landscape-scale problems. Forest collaboratives are assumed to be heterogeneous, consisting of stakeholders with a diverse range of interests. Few studies have systematically explored variables associated with collaborative composition. We identify six elements of collaborative composition for investigation: size, stakeholder diversity, balance, locality–diversity, core attendance, and cross-participation. This...

(1) Background: Analyses using participatory GIS (PGIS) data have primarily focused on reporting landscape values (e.g., subsistence, spiritual) or activities (e.g., hunting, meditation) and less frequently on identifying patterns of value and activity co-occurrence. This paper explores whether consistent combinations of landscape values and activities associated with meaningful places identified by visitors—referred to as “bundles”—emerge across protected areas. These bundles represent the cognitive-behavioral components of sense of place. (2) Methods: We used exploratory factor analysis...

Wildfires have the potential to profoundly alter forest structure, which can leave land managers with severe information gaps when making post-fire forest management decisions. We assess point clouds derived from aerial lidar (16.8 points/m²) and digital aerial photogrammetry (DAP, 13.9 points/m²) for the purposes of generating post-fire forest attribute maps using 82 permanent field plots. Low-cost aerial lidar and DAP data can enable predictive mapping after fires occur, and an assessment of the utility of DAP in this context is warranted given its lower cost. We evaluated the performance...

Climate change is reducing snowpack across temperate regions with negative consequences for human and natural systems. Because forest canopies create microclimates that preserve snowpack, managing forests to support snow refugia—defined here as areas that remain relatively buffered from contemporary climate change over time that sustain snow quality, quantity, and/or timing appropriate to the landscape—could reduce climate change impacts on snow cover, sustaining the benefits of snow. We review the current understanding of how forest canopies affect snow, finding that while closed-conifer...

Tree regeneration in northern temperate and southern boreal forests is threatened by multiple factors, including over-browsing by ungulates such as white-tailed deer (Odocoileus virginiana). However, characterizing the effects of deer browse on tree regeneration at regional scales has been challenging due to (a) the lack of reliable indicators of browsing intensity and (b) the fact that browsing impacts are likely to vary by seedling size yet coarse metrics are often used to capture this seedling attribute. To address these challenges, we modeled effects of white-tailed deer browse and...

Forest drought monitoring tools are crucial for managing tree water stress and enhancing ecosystem resilience. The Forest Drought Response Index (ForDRI) was developed to monitor drought conditions in forested areas across the contiguous United States (CONUS), integrating vegetation health, climate data, groundwater, and soil moisture content. This study evaluated ForDRI using Pearson correlations with the Bowen Ratio (BR) at 24 Ameri- Flux sites and Spearman correlations with the Tree-Ring Growth Index (TRSGI) at 135 sites, along with feedback from 58 stakeholders. CONUS was divided into...

Rapid ‘ōhiʻa death (ROD), caused by fungal pathogens Ceratocystis lukuohia and Ceratocystis huliohia, is devastating ʻōhiʻa (Metrosideros polymorpha), the keystone forest tree species of Hawaiʻi. Ceratocystidaceae fungi produce fruity volatile organic compounds (VOCs) and sticky sexual spores, suggesting they are adapted for insect dispersal. In this study, we explored chemical signaling of the causal agents of the ROD disease complex and how those VOCs mediate ambrosia beetle (Coleoptera: Curculiondiae: Scolytidae)-plant interactions. Four species of ambrosia beetles (Xyleborinus saxesenii...

In Michigan, United States of America, where Asian parasitoids were released to manage emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), we monitored four native parasitoids that also attack the invasive beetle – Atanycolus cappaerti Marsh and Strazanac, A. simplex (Cresson), and Spathius laflammei Provancher (all Hymenoptera: Braconidae), and Phasgonophora sulcata Westwood (Hymenoptera: Chalcididae) – using yellow pan traps and tree dissections. Adult A. cappaerti, followed by A. simplex, had the broadest seasonal activity, S. laflammei was captured primarily in...

In the United States, ecosystems regularly experience wildfires and as fire seasons lengthen, fires are becoming a more important disturbance. While all types of disturbance have impacts on the carbon cycle, fires result in immediate emissions into the atmosphere. To assist managers in assessing wildland fire impacts, particularly on federally managed land, we developed estimates of area burned and related emissions for a 21-year period. These estimates are based on wildland fires defined by the interagency Monitoring Trends in Burn Severity database; emissions are simulated through the...