Treesearch

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 the United States, the forest products industry loses an estimated $500 million to $1 billion annually to illegal logging. Once illegally harvested wood is removed from the forest, it’s difficult for USDA Forest Service law enforcement to prove beyond a reasonable doubt that the wood was illegally harvested. The use of DNA is a recent development that can help law enforcement determine if wood is illegally sourced. Researchers Rich Cronn and Laura Hauck with the Forest Service’s Pacific Northwest Research Station developed DNA forensic protocols to evaluate bigleaf maple wood products...

Alaska is a land of extremes. This includes its climate, which ranges from mild to maritime in its southeast, to arctic in its northern slope. Alaska is also at the forefront of experiencing changes in climate and climate variability, including higher temperatures and more precipitation. Over the past century, changes in climate have already led to a longer growing season that has expanded areas suitable for agricultural production. Along with improving opportunities for agricultural production, climate change will also bring challenges, such as increased risks of invasive species, pests,...

An estimated 128 M trees died during the 2012–2016 California drought, largely in the southern Sierra Nevada Range. Prescribed burning and mechanical thinning are widely used to reduce fuels and restore ecosystem properties, but it is unclear if these treatments improve tree growth and vigor during extreme drought. This study examined tree growth responses after thinning, prescribed burning, and extreme drought at the Teakettle Experimental Forest, a historically frequent fire mixed-conifer forest in the southern Sierra Nevada of California, USA. Mechanical thinning (no thin, understory...

Mountain watersheds often contain a mosaic of glacier-, snow-, and rain-fed streams that have distinct hydrologic, temperature, and biogeochemical regimes. However, as glaciers diminish and precipitation shifts from snow to rain, the physical and chemical characteristics that make glacial or snowmelt streams distinct from rain-fed streams will fade. Among the unforeseen consequences of this hydrologic homogenization could be the loss of unique food webs that sustain aquatic consumers. To explore the impacts of a melting cryosphere on stream food webs, we parameterized an aquatic food web...

Degraded floodplains and valley floors are restored with the goal of enhancing habitat for native fish and aquatic-riparian biota and the protection or improvement of water quality. Recent years have seen a shift toward “process-based restoration” that is intended to reestablish compromised ecogeomorphic processes resulting from site- or watershed-scale degradation. One form of process-based restoration has developed in the Pacific Northwest, United States, that is intended to reconnect rivers to their floodplains by slowing down flows of sediment, water, and nutrients to encourage lateral...

This is the fourth in a series of periodic monitoring reports on status and trends of forests used by northern spotted owls (Strix occidentalis caurina; NSO) for nesting, roosting, and dispersal on federally administered lands within the Northwest Forest Plan (NWFP) area (NSO range in the United States) since its implementation in 1994. The objective of this monitoring is to determine if federal forest lands are providing sufficient conservation of forests that are important elements of NSO habitat, and thus populations. Here we present models on the amount, distribution, and spatial...

Species coexistence is governed by availability of resources and intraguild interactions including strategies to reduce ecological overlap. Gray foxes are dietary generalist mesopredators expected to benefit from anthropogenic disturbance, but populations have declined across the midwestern USA, including severe local extirpation rates coinciding with high coyote and domestic dog occurrence and low red fox occurrence. We used data from a large-scale camera trap survey in southern Illinois, USA to quantify intraguild spatial and temporal interactions among the canid guild including domestic...

Classical biological control, the introduction of natural enemies to new environments to control unwanted pests or weeds, is, despite numerous successful examples, associated with rising concerns about unwanted environmental impacts such as population decline of nontarget species. Recognition of these biosafety risks is globally increasing, and prerelease assessments of biological control agents (BCAs) have become more rigorous in many countries. We review the current approaches to risk assessment for BCAs as used in Australasia, Europe, and North America. Traditionally, these assessments...