Treesearch

Forest management objectives continue to evolve as the desires and needs of society change. The practice of silviculture has risen to the challenge by supplying silvicultural methods and systems to produce desired stand and forest structures and compositions to meet these changing objectives. For the most part, the practice of silviculture offers a robust set of procedures well suited for the timely and efficient production of timber crops but too often leaves simplified forests that do not necessarily reflect historical conditions, do not provide a full range of wildlife habitats, nor...

The Kings River Experimental Watershed (KREW) is a watershed-level study on headwater streams in the Sierra Nevada, California. Eight perennial streams, from 1500 m (4920 ft) to 2490 m (8170 ft) elevation, have been instrumented and collecting data since 2002. Component research areas of the study include stream flow, water chemistry, sediment, soil chemistry, stream invertebrates, stream algae, riparian and upland vegetation and meteorology. The KREW is part of a larger project called the Kings River Project (KRP). The KRP is a collaboration between the Pacific Southwest Research Station...

The widespread effort to reduce fuel hazards in western forested ecosystems places significant emphasis on surface and small ladder fuels. Changes in canopy density, for purposes of either reducing potential crown fire impacts or insect/pathogen-related mortality, are less frequently considered. Providing a sound basis for treating more than surface and small ladder fuels is possible and can be smoothly integrated with most fuel reduction proposed actions. This paper illustrates a strategy that has potential to accomplish this goal.

In the past, fires set by American Indians and settlers shaped much of the southern Appalachian forest by reducing the shrub layer and maintaining an open understory. Since the 1930’s, fire exclusion has allowed the development of a thick shrub layer and accumulation of woody debris. This fuel buildup contributes to the potential for wildfire in many ecosystems. Recently, the need for fuel reduction, using techniques such as prescribed fire or mechanical treatments, has received national attention. However, the impacts of such habitat manipulations on breeding birds are not well understood,...

Fire injury was characterized and survival monitored for 5,246 trees from five wildfires in California that occurred between 1999 and 2002. Logistic regression models for predicting the probability of mortality were developed for incense-cedar, Jeffrey pine, ponderosa pine, red fir and white fir. Two-year post-fire preliminary models were developed for incense-cedar, Jeffrey pine, ponderosa pine and white fir. Three- and four-year post-fire models are presented for white fir and red fir, respectively. Mortality was predicted using percent crown length kill and cambium kill in all optimal...

Mixed conifer forests cover 7.9 million acres of California’s total land base. Forest structure in these forests has been influenced by harvest practices and silvicultural systems implemented since the beginning of the California Gold Rush in 1849. Today, the role of fire in coniferous forests, both in shaping past stand structure and its ability to shape future structure, is a central force driving both the direction and political debate around forest management on public lands. The purpose of this paper is to demonstrate stand structures which contribute to effective fuel treatments and...

Many wildfire events have burned thousands of hectares across the western United States, such as the Bitterroot (Montana), Rodeo-Chediski (Arizona), Hayman (Colorado), and Biscuit (Oregon) fires. These events led to Congress enacting the Healthy Forest Restoration Act of 2003, which, with other policies, encourages federal and state agencies to decrease wildfire risks by evaluating, prioritizing, and implementing vegetation treatments across large landscapes. Land management agencies, and society, have high expectations that vegetation (fuel) treatments and forest restoration activities...

Experimental canopy gaps ranging in size from 0.1 to 1.0 ha (0.25 to 2.5 acres) were created in a mature mixed conifer forest at Blodgett Forest Research Station, California. Following gap creation, six species were planted in a wagon-wheel design and assessed for survival after two growing seasons. Study trees were measured after seven years to describe the effect of gap size on early growth of planted trees. Giant sequoia had the lowest mortality (2.4 – 5.0 percent), sugar pine, incense-cedar, ponderosa pine, and Douglas-fir all had comparable levels of mortality (5.8 - 18.9 percent),...

One of the difficulties of apportioning growing stock across diameter classes in multi- or uneven-aged forests is estimating how closely the target stocking value compares to the maximum stocking that could occur in a particular forest type and eco-region. Although the BDQ method had been used to develop uneven-aged prescriptions, it is not inherently related to any maximum stocking guide. Adapting Stand Density Index (SDI) to uneven-aged silviculture by apportioning stocking equally in all diameter classes has been proposed. SDImax is the maximum stocking possible for a given species and...

The Fire and Fire Surrogate Study utilizes forest thinning and prescribed burning in attempt to create forest stand structures that reduce the risk of catastrophic wildfire. Replicated treatments consisting of mechanical tree harvest (commercial harvest plus mastication of submerchantable material), mechanical harvest followed by prescribed fire, prescribed fire alone, and no-treatment controls, were completed at the Blodgett Forest Research Station in fall 2002. We conducted pre-treatment and post-treatment assessments of soil physical, chemical, and biological characteristics. Soil bulk...