Treesearch

Aggressive bark beetles colonize and kill healthy conifers through pheromone-mediated mass aggregation. In several species, the focal point of aggregation moves progressively from mass-attacked ‘focus trees’ to adjacent, unattacked ‘recipient trees’, resulting in infestation growth. This process, termed ‘switching’, is hypothesized to be mediated in whole or in part by antiaggregation pheromones released by beetles as colonization intensifies on a focus tree. We tested this hypothesis with the southern pine beetle, Dendroctonus frontalis Zimmermann (Coleoptera: Curculionidae: Scolytinae),...

Changes in global bioenergy consumption have catalyzed the emergence of forest plantations as an important energy alternative. In the southeastern United States, land cover changes caused by increasing demands for pine trees as a bioenergy feedstock incite associated impacts on local ecosystem services (e.g., water yield). However, water yield impacts from pine plantation management strategies, such as thinning and short rotation, have yet to be simultaneously examined on multiple spatial scales. Here, we modeled the effects of thinning and clear-cut conditions on long term mean annual...

The varied and wide-reaching impacts of climate change are occurring across heterogeneous landscapes characterized by a broad diversity of soil types. Despite the known importance of soils in mediating biogeochemical nutrient cycling, there is little experimental evidence of how soil characteristics may shape aqueous nutrient losses from forest ecosystems under climate change. Our objective was to clarify how soil characteristics modify the impact of climate changes on carbon and nutrient leaching losses in temperate forests. We therefore conducted a field-based mesocosm experiment with...

Public participation processes influencing National Forest management in the United States have shifted significantly because of the global COVID-19 pandemic. Although the United States Forest Service has used virtual participation tools in the past to support participation, the pandemic was the first time staff had to solely rely on such methods. Using the Trinity of Voice theory concepts of access, standing, and influence, we discuss how each has been and can be impacted by virtual vs. in- person public participation in federal land governance. Lessons are drawn from two peer-to-peer...

Climate classification allows an efficient encapsulation of climate data into climate units. For North America and most of Central America during 20, 14, 13, 11, 10, 7, 5, and 1 thousand years ago (ka) and recent years, I applied a Köppen-Trewartha classification system, but with dry classes subsumed under primary thermal classes to preserve information. The boreal and polar classes decreased from a combined 70% of area during 20 ka until reaching 42% of area at 7 ka, after which the area remained relatively stable. Conversely, the subtropical and temperate classes increased from 25% of...

For over two decades, Forest Stewardship Council (FSC) certification for community forestry has occurred in tropical countries. However, community forests represent just over 1% of the total FSC-certified forest area worldwide. Certification can promote more socially and environmentally responsible forest management while delivering economic returns to communities, but communities face challenges to obtaining, maintaining, and benefiting from it. Our analysis of the published literature finds that community forestry certification delivers many social and environmental benefits, often more...

In Africa, forest tenure reform to decentralize forest management from central governments to local communities has been occurring since the 1990s to promote forest conservation, poverty alleviation, and sustainable forest-based livelihoods. African governments and donor organizations continue to invest in community forestry, raising the question of what contributes to "success." The present study examines social, economic, and biophysical factors that contribute to success, or lack thereof, in community forestry in southeastern Tanzania. There, community forest enterprises produce...

In their seminal paper, Shea and Chesson (Trends in Ecology & Evolution, 2002, 17, 170) developed a highly cited model (S&C model) showing scale dependency in the native–exotic richness relationships. Two decades later, extensive additional data have been accumulated, leading to new findings and insights. Accordingly, two updates were made here to the original S&C model: (1) changing the “negative” richness relationship between natives and exotics to “non-consistent” or “non-significant”; and (2) modifying the original diagram to correctly represent native and exotic species richness...

Development of electronic technologies for precise identification of fruit crop cultivars in agricultural production provides an effective means for assuring product quality and authentication. The capabilities of discriminating between grape (Vitis vinifera L.) cultivars is essential for assuring certification of varieties sold in world markets. Machine olfaction, based on electronic-nose (e-nose) technologies, is readily available for rapid identification of fruit and vegetative agricultural products. This technology relies on detection of and discrimination between volatile organic...

Pistachio is one of the most economically important nut crops worldwide. However, there are no reports describing the chloroplast genome of this important fruit tree. In this investigation, we assembled and characterized the complete pistachio chloroplast sequence. The Pistacia vera chloroplast genome was 160,598 bp in size, similar to other members of Anacardiaceae (149,011–172,199 bp) and exhibited the typical four section structure, including a large single copy region (88,174 bp), a small single copy region (19,330 bp), and a pair of inverted repeats regions (26,547 bp). The genome...