Treesearch

Background: Although the importance of using local provenance planting stock for woodland production, habitat conservation and restoration remains contentious, the concept is easy to understand, attractive and easy to ‘sell’. With limited information about the extent and scale of adaptive variation in native trees, discussion about suitable seed sources often emphasises “local” in a very narrow sense or within political boundaries, rather than being based on sound evidence of the scale over which adaptation occurs. Concerns exist over the actual scale (magnitude and spatial scale) of...

Climate change poses significant threats to Pacific coastal rainforests of North America. Land managers currently lack a coordinated climate change adaptation approach with which to prepare the region's globally outstanding biodiversity for accelerating change. We provided analyses intended to inform coordinated adaptation for eight focal rainforest tree species of commercial importance and broad rainforest communities. By using two different approaches to determine vulnerability, including climate envelope modeling (Maxent) and the MC1 dynamic vegetation model, we were able to assess...

Due to their hydraulic system that allows them to transport water from the soil to leaves, woody plants have become incredibly successful in terrestrial ecosystems since their evolution ~400 million years ago (Hartmann 2011). This vascular system lets trees conduct water from the soil up to more than 100 m (Koch et al. 2004), allowing trees to compete for light and absorb several petagrams of carbon from the atmosphere via photosynthesis every year (Le Quéré et al. 2009). Thus, plant hydraulics form the “backbone” of most terrestrial ecosystems, facilitating net primary production and...

Summary 1. The provisioning of ecosystem services to society is increasingly under pressure from global change. Changing disturbance regimes are of particular concern in this context due to their high potential impact on ecosystem structure, function and composition. Resiliencebased stewardship is advocated to address these changes in ecosystem management, but its operational implementation has remained challenging. 2. We review observed and expected changes in disturbance regimes and their potential impacts on provisioning, regulating, cultural and supporting ecosystem services, concentrat...

In the western United States, climate warming poses a unique threat to water and snow hydrology because much of the snowpack accumulates at temperatures near 0 °C. As the climate continues to warm, much of the region's precipitation is expected to switch from snow to rain, causing flashier hydrographs, earlier inflow to reservoirs, and reduced spring and summer snowpack. This study investigates historical variability in snow to precipitation proportion (Sf) and maps areas in the western United States that have demonstrated higher Sf sensitivity to warming in the past. Projected changes in...

The U.S. Geological Survey’s Gap Analysis Program (hereafter, GAP) is a nationally based program that uses land cover, vertebrate distributions, and land ownership to identify locations where gaps in conservation coverage exist, and GAP products are commonly used by government agencies, nongovernmental organizations, and private citizens. The GAP land-cover designations are based on satellite-derived data, and although these data are widely available, these data do not capture the 3-dimensional vegetation architecture that may be important in describing vertebrate distributions. To date,...

Disasters result from hazards affecting vulnerable people. Most disasters research by anthropologists focuses on vulnerability; this article focuses on natural hazards. We use the case of wildfire mitigation on United States Forest Service lands in the northwestern United States to examine social, political, and economic variables at multiple scales that influence fire hazard and risk reduction treatments and their effectiveness. Variables highlighted include policy direction to prioritize wildfire risk reduction in the wildland-urban interface, laws and policies that make treating fuels...

The U.S. Fish and Wildlife Service recently revised the recovery plan (USFWS, 2011) and designated Critical Habitat (USFWS, 2012a) for the Northern Spotted Owl (Strix occidentalis caurina). The Critical Habitat designation was based in part on a map of relative habitat suitability that was developed by USFWS (2011, 2012b) for this purpose. Loehle et al. (2015) critiqued the U.S. Fish and Wildlife Service’s approach to modeling relative habitat suitability for the Northern Spotted Owl. Here, we respond to Loehle et al.’s assessment, and identify four major shortcomings within it. First, it...

The history of land use in the American West has traditionally been one of conflict, but the divisive relationships between ranchers, foresters, land management agencies, recreational users, and conservationists are transforming. Grassroots coalitions have developed among unlikely allies. Together, they are advocating for management approaches that incorporate local knowledge, community needs, and sound environmental stewardship. This "collaborative conservation" is especially appropriate for promoting the conservation of working forests and rangelands, which are critical for maintaining...

Shore pine, which is a subspecies of lodgepole pine, was a widespread and dominant tree species in Southeast Alaska during the early Holocene. At present, the distribution of shore pine in Alaska is restricted to coastal bogs and fens, likely by competition with Sitka spruce and Western hemlock. Monitoring of permanent plots as part of the United States Forest Service Forest Inventory and Analysis program identified a recent loss of shore pine biomass in Southeast Alaska. The apparent loss of shore pine is concerning, because its presence adds a vertical dimension to coastal wetlands,...