Treesearch

Forest management decisions can have both positive and negative impacts on biodiversity, including bird species. Silvicultural treatments such as thinning, single-tree selection, and other methods can influence bird abundance and diversity because different species have different habitat, diet, breeding, and migration needs. To better understand how forest management activities affect bird populations, researchers conducted a meta-analysis that focused on two types of species in eastern North America during the breeding season: mature-forest species and shrubland species. The research team...

This is a special International Poplar Commission (IPC) working party communication and outreach that provides a brief overview and outcomes of agroforestry systems around the world.

Sequestration and storage of organic carbon (C) in soil is an essential component of climate change mitigation and fundamental in promoting the health and climate resilience of soils. Sources of available soil C data are increasing, which complicates efforts to consolidate the data in forms that can be readily used by stakeholders. Spatial and temporal gaps in data availability also limit the quantification of changes in soil C through space and time. Improved coordination among producers and users of soil C data would provide data compatibility at the spatial and temporal resolution...

Introduction: Larvae of the invasive emerald ash borer [EAB, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae)], kill over 99% of green ash (Fraxinus pennsylvanica Marshall) trees they infest, yet a small percentage of green ash ("lingering ash") survive years of heavy EAB attack. In the face of an ongoing invasion that threatens multiple North American Fraxinus species with extinction, any evidence for reproducible defensive responses in the native species merits investigation. Methods: We evaluated the capacity of three families of green ash F1 progeny to kill EAB larvae when...

This brief paper provides guidance for using the most recent USFS science TCC data in local community-scale applications. It illustrates a comparison between the percent tree canopy cover for six cities of the United States generated from estimations of TCC based on the USFS science maps versus estimations of TCC based on photointerpretation of high-resolution Google Earth imagery from the same vintage. Please note and consider the results of this and previous analyses (some referenced below) as you evaluate the use of USFS TCC in forest management plans or other assessments.

Urbanization increasingly causes alterations in prey diversity and abundance, land cover, and human disturbance, subsequently impacting populations of even the most adaptable species. American Kestrels are currently considered urban adapters, which may be veiling the influence of urbanization on their continental population decline. We quantified overwintering abundance and sex ratios of American Kestrels throughout the past three decades in a rapidly developing region of the species’ wintering range in southeast Florida to study spatial and temporal population trends relative to degree of...

Few previous studies have described the patterns of leaf characteristics in response to nutrient availability and depth in the crown. Sugar maple has been studied for both sensitivity to light, as a shade-tolerant species, and sensitivity to soil nutrient availability, as a species in decline due to acid rain. To explore leaf characteristics from the top to bottom of the canopy, we collected leaves along a vertical gradient within mature sugar maple crowns in a full-factorial nitrogen (N) by phosphorus (P) addition experiment in three forest stands in central New Hampshire, USA. Thirty-two...

Stream fluxes are commonly reported without a complete accounting for uncertainty in the estimates, which makes it difficult to evaluate the significance of findings or to identify where to direct efforts to improve monitoring programs. At the Hubbard Brook Experimental Forest in the White Mountains of New Hampshire, USA, stream flow has been monitored continuously and solute concentrations have been sampled approximately weekly in small, gaged headwater streams since 1963, yet comprehensive uncertainty analyses have not been reported. We propagated uncertainty in the stage height–discharge...

Upland oak trees are ecologically, economically, and socially important across the central and eastern United States, but they are at risk of decline from myriad threats. Most of the forestland in this region is held by families and individuals (family forest owners, FFOs), so the future of these oak forests largely depends on the decisions they make about their land. We surveyed 20,000 FFOs and received 1,517 responses to better understand their attitudes towards upland oak forests and management practices that can be used to support oak, specifically harvesting, planting, using herbicides...

Complex adaptive systems (CASs), from ecosystems to economies, are open systems and inherently dependent on external conditions. While a system can transition from one state to another based on the magnitude of change in external conditions, the rate of change—irrespective of magnitude—may also lead to system state changes due to a phenomenon known as a rate-induced transition (RIT). This study presents a novel framework that captures RITs in CASs through a local model and a network extension where each node contributes to the structural adaptability of others. Our findings reveal how RITs...