Treesearch

Cistaceae are shrubs, subshrubs and herbs that often occur in stressful, fire-prone or disturbed environments and form ectomycorrhizal (ECM) associations with symbiotic fungi. Although some Cistaceae are long-lived shrubs that grow to significant size, others are herbaceous annuals or short-lived plants. Thus, Cistaceae are atypical ECM hosts that are fundamentally different in their biology from trees that are the more typically studied ECM hosts. The Mediterranean region is the center of diversity for Cistaceae and the ectomycorrhizal fungi associated with Cistaceae hosts have primarily...

The physical structure of forest canopies regulates numerous ecological processes and functions, and management strategies to promote specific structural features, such as high structural complexity, are increasingly desired. Partial disturbances — including partial harvests — can modify forest canopy structure, but their specific effects may be influenced by differences in characteristics such as intensity and frequency. Understanding the variable effects of silvicultural treatments on canopy structure will be essential to designing silvicultural regimes that can promote canopy structural...

1. In the temperate mixed oak forests of Central Europe, outbreaks of insects such as the spongy moth, Lymantria dispar, can cause severe defoliation and insecticide is sometimes applied for their control. Parasitoids, mainly Hymenoptera and Diptera, are among the most diverse and important natural enemies of caterpillars in these forests. However, due to their cryptic lifestyle and taxonomic difficulties, we lack knowledge on the impact of insecticide applications on complex host-parasitoid networks. 2. In a large-scale field experiment, we tested the effect of spraying the lepidopteran-sp...

Developed river corridors, resistant bedrock, steep channels, and confined valleys predispose New England to flooding. The region has experienced substantial flooding in recent years, which may continue due to rising temperatures and increased precipitation. To reduce future flooding, intervention is necessary. In a recent publication, research biologist Keith Nislow, U.S. Department of Agriculture, Forest Service, Northern Research Station, and colleagues introduced “Slow the Flow for Climate Resilience” (SFCR), a strategy that municipalities and practitioners can adopt to manage floods...

Prescribed burning is a cost-effective method for reducing hazardous fuels in pine- and oak-dominated forests, but smoke emissions contribute to atmospheric pollutant loads, and the potential exists for exceeding federal air quality standards designed to protect human health. Fire behavior during prescribed burns influences above-canopy sensible heat flux and turbulent kinetic energy (TKE) in buoyant plumes, affecting the lofting and dispersion of smoke. A more comprehensive understanding of how enhanced energy fluxes and turbulence are related during the passage of flame fronts could...

Boreal forests form the largest terrestrial biome globally. Climate change is expected to induce large changes in vegetation of high latitude ecosystems, but there is considerable uncertainty about where, when, and how those changes will occur. Such vegetation change produces major feedback to the climate system, including by modifying albedo (reflectivity). Our study used the LANDIS-II forest landscape model to project forest dynamics on four representative landscapes (1 M ha) for 280 years into the future under a range of climate scenarios across a broad latitudinal gradient in Siberia....

Urban parks provide vital social, environmental and health benefits to residents. However, the spatial distribution of parks, and the amenities they provide, may not be equitably distributed within cities. We examine the accessibility of urban parks with different social, environmental and health amenities by race and ethnicity. We identified 122,988 urban parks across the USA, measured the racial/ethnic population distribution within a 10-min walkshed around each park and compared these distributions to the overall demographics of the city. We found that the spatial distribution of parks...

Understanding how different tree species affect soil microbial communities is crucial for sustainable forestry and ecosystem management practices. Despite Black walnut (Juglans nigra L.) forestry having a rich history, the overall comprehension of how this hardwood species influences soil remains incomplete. In earlier studies, we examined the effects of hardwood plantations on soil chemical properties and their interaction with microbial biomass, however, we highlight the importance of studying the soil microbial communities and their relationship with soil properties in greater depth....

Soil fungal communities are critical for forest ecosystem functions in the Central Hardwood Region (CHR) of the USA. This evaluation, which took place in 2022–2023, investigates the influence of Juglans nigra (BW, black walnut) and Quercus rubra (NRO, Northern red oak) on soil properties and fungal community structures across three CHR sites. The objectives of this study are to investigate how the fungal communities identified beneath J. nigra and Q. rubra serve to influence biodiversity and soil health within hardwood plantations. Soils from two locations in Indiana and one in Michigan...

Black walnut (Juglans nigra) has an estimated population of more than 340 million trees and 4.9 billion cubic feet of net volume on forest land across the eastern United States. Over the past decade, the number and net volume of black walnut trees have increased by 11 percent and 23 percent, respectively. This article will examine the factors driving these increases as well as other important variables such as tree damage and seedling regeneration using the latest data from the USDA Forest Service’s Forest Inventory and Analysis (FIA) program. Although orchards are excluded, the analyses...