Treesearch

The principal findings of the 11th forest survey of Alabama (2020) and changes that have occurred since the previous surveys are presented. Topics examined include forest area, ownership, forest-type groups, stand structure, basal area, timber volume, growth, removals, mortality, and timber products. Alabama’s contribution to the Nation’s forest resources and regional comparisons are detailed.

The problem of biological invasions is largely an inadvertent result of globalization. Global trade and human travel have resulted in the accidental movement of organisms across geographic barriers such as oceans and major mountain ranges that previously compartmentalized the world's flora and fauna through millions of years of evolution. Most non-native organisms established outside their range are inconsequential, with little noticeable impact on invaded ecosystems. However, a fraction of non-native species become extremely abundant and/or greatly alter ecosystem processes and properties...

The actions urban forest managers, ecologists, and community stewards undertake to review and comment on new development plans and to plant, remove, and otherwise manage trees in cities have implications for local wildlife habitat and biodiversity. Far too often, these influences do not receive enough attention unless threatened and endangered species are present, or if residents make it an issue. This article puts a spotlight on the impacts of urbanization on ecological communities and biodiversity, and how urban and community plans, policies, and actions can make a difference in improving...

Disturbances to forested watersheds often result in increases of nutrients and light to nearby streams. Such changes are generally expected to produce a shift to a more autotrophic aquatic ecosystem, with measurable increases in algae, and associated implications for food webs and fisheries. Although this paradigm is widely established, results from our 10-year study (2007–2016) in 12 headwater streams and four sites downstream in the Trask River Watershed (Oregon, USA), did not concur. In 2012, one watershed was thinned, three were clearcut harvested with variable buffers and three with...

With climate change and ongoing impacts from human development and resource extraction, US federal land management agencies are acutely concerned with managing for healthy aquatic ecosystems in the Southern Appalachian Mountain (SAM) Region. Here, we describe development of a spatial decision support application to assess the biological and ecological impacts of atmospheric S and N deposition on aquatic ecosystems of the region. We first summarize foundational published work to predict continuous maps of surface water acid neutralizing capacity (ANC) and soil base cation weathering (BCw)....

Statistical confidence in estimates of timber volume, carbon storage, and other forest attributes depends, in part, on the uncertainty in field measurements. Surprisingly, measurement uncertainty is rarely reported, even though national forest inventories routinely repeat field measurements for quality assurance. We compared measurements made by field crews and quality assurance crews in the Forest Inventory and Analysis program of the U.S. Forest Service, using data from 2790 plots and 51 740 trees and saplings across the 24 states of the Northern Region.We characterized uncertainty in 12...

In October 2011, the Halloween Nor'easter produced unusually early and heavy snowfall while leaves were still on the trees, causing extensive damage throughout the northeastern United States. This storm is an example of winter weather whiplash, in which an abrupt, back-and-forth swing in winter weather affects coupled human and natural systems. Research on the social-ecological drivers and impacts of winter weather whiplash is scarce because most studies only consider meteorological causes and consequences of extreme events. In this study, we used publicly available data of snowfall...

Dry conifer forests in the western US historically experienced frequent fire prior to European American colonization. Mean fire return interval ranged from about 5-35 years, with the majority of fires burning at low-to-moderate severity. The arrival of European Americans initiated notable reductions in fire frequency through the cessation of Indigenous burning, livestock grazing, and fire suppression. These activities effectively excluded fire from most dry conifer forests, thereby allowing live and dead fuels to accumulate. There are concerns that this fuel accumulation is causing...

This is the executive summary for the report, Climate Change Vulnerability and Adaptation in the Columbia River Gorge National Scenic Area, Mount Hood National Forest, and Willamette National Forest, by Halofsky et al. (2022, PNW-GTR-1001). The vulnerability and adaptation assessment was conducted by a science-management partnership comprising of the three U.S. Department of Agriculture Forest Service units, Forest Service scientists, and other organizations. The partnership assessed the vulnerability of natural resources to climate change and developed adaptation options that minimize...

Fungal pathogens of the genus Ceratocystisrecently introduced to the Island of Hawaiʻi have killed hundreds of thousands of native ‘Ōhiʻa trees, an ecologically and culturally important keystone species. Symptoms of the associated disease, Rapid ‘Ōhiʻa Death (ROD), have been found to be easily detectable with high resolution imaging spectroscopy. We used wall-to-wall maps of affected ‘Ōhiʻa canopy built in four consecutive years (2016–2019) to analyze how changes in the distribution and density of browning canopy detections over this time period corresponded to environmental drivers at two...