Treesearch

Trees make our cities more attractive and provide many ecosystem services, including air quality improvement, energy conservation, stormwater interception, and atmospheric carbon dioxide reduction. These benefits must be weighed against the costs of maintaining trees, including planting, pruning, irrigation, administration, pest control, liability, cleanup, and removal. We present benefits and costs for representative small, medium, and large deciduous trees and coniferous trees in the Northern California Coast region derived from models based on research carried out in Berkeley, California...

Climate change and its effects are writ large across the landscape and in the natural and cultural heritage ofparks and wilderness. They always have been and always will be. The sculpted walls of Yosemite National Park and the jagged scenery ofthe Sierra Nevada wilderness would not be as spectacular if periods of glaciation had not been followed by periods of deglaciation. High biodiversity in forests ofthe Great Smoky Mountains reflects a legacy of climate change, migrating species, and isolated climatic refugia. Fossils unearthed at Dinosaur National Monument reflect a time when the...

On a dry afternoon in September of 2007 the “Moonlight Fire” started in a northeastern California mixed-conifer forest that had been accumulating fuels for over a century. Twelve days later the fire was contained after burning 65,000 acres, destroying seven structures, injuring 34 firefighters, and costing $32 million. Much of the forest within the fire perimeter had not been treated to reduce fuels because the area contained 22 protected areas set aside as habitat for two threatened species, the spotted owl (Strix occidentalis) and northern goshawk (Accipiter gentilis). A year after the...

As described in Chapter 2, protected area managers have been directed, through statutes and agency policy, to preserve natural conditions in parks and wilderness. Although preserving naturalness has always been a challenge for managers, there has never been much question about whether this is the right thing to do. But given what is known now about the pace and magnitude of ongoing global changes, the appropriateness of naturalness as a management goal must be reexamined. A host of anthropogenic environmental stressors are reshaping ecosystems, including those protected in parks and...

Sustainable operations (SO; operating in an environmentally, economically, and socially sustainable manner) is consistent with the environmental stewardship mission of natural resource management organizations. This study sought to examine SO practices in the daily work lives of US Forest Service employees, including those primarily stationed in the office and in the field. The purpose was to identify influences on these behaviors such that organizations can more effectively promote them. We surveyed a random sample of employees within a region and research station of the US Forest Service...

We used a rapid assessment to survey American pika (Ochotona princeps) populations and documented 420 pika site occurrences in southwestern U.S.A. These included 329 sites from the Sierra Nevada (SN), California; 67 from six southwestern Great Basin (swGB) ranges, California and Nevada; 16 from three central Great Basin ranges, Nevada; and 8 from the central Oregon Cascades. Of these, 67% were currently occupied, 27% modern (indirectly scored active), and 6% old. Sites were grouped into 148 demes, 88 regions, and 11 mountain ranges. Current elevations ranged from 1645 m (1827 m excluding...

It would appear that forests are finally having their day—and not a moment too soon. Around the world, trees are dying at an alarming rate, besieged by illegal logging, agricultural conversion, wildfire, and drought. According to the United Nations Food and Agriculture Organization, 13 million hectares of the world’s forests are now lost to deforestation every year. In North America, climate change, insect invasions, and urban sprawl are altering and shrinking suitable forest habitat for critical wildlife species. Clearly, forests need new conservation and management strategies.

From 1997 to 2006, we used mark–recapture models to estimate the site fidelity of 1250 Sierra Nevada yellow-legged frogs (Rana sierrae) in Kings Canyon National Park, California, USA, during their three main activity periods of overwintering, breeding, and feeding. To quantify site fidelity, the tendency to return to and reuse previously occupied habitats, we used multistrata models (with water bodies as the strata) and potential function analyses. The probability of returning to previously used water bodies during all activity periods was typically greater than 80% and always greater than...

Spatial patterns of animals have important implications for population dynamics and can reveal other key aspects of a species' ecology. Movements and the resulting spatial arrangements have fitness and genetic consequences for both individuals and populations. We studied the spatial and dispersal patterns of the Oregon Gartersnake, Thamnophis atratus hydrophilus, using capture–recapture techniques. Snakes showed aggregated dispersion. Frequency distributions of movement distances were leptokurtic; the degree of kurtosis was highest for juvenile males and lowest for adult females. Males...

In the past, researchers from the Pacific Southwest Research Station (PSW) undertook forest growth studies to evaluate how best to manage timber resources. However, historical and future data collected at PSW growth plots also have the potential to increase our understanding of the ecological processes occurring in our forests and shed light on national issues of importance. This report provides information on the history, geography, plant species studied, installation, and measurement interval of each plot along with a list of publications arising from data gathered at these plots. This...