Treesearch

The fire hazard in many western forests is unacceptably high, posing risks to human health and property, wildlife habitat, and air and water quality. Cost is an inhibiting factor for reducing hazardous fuel, given the amount of acreage needing treatment. Thinning overly dense forests is one way to reduce fuel loads. Much of the product removed during these treatments has traditionally been considered unmerchantable, but this is changing with the growing interest in biofuel and bioelectricity. Wood can be used to produce both. Potential may exist in some areas to sell the biomass removed...

Although stream protection has become a central tenet of forest management in the Pacific Northwest, it is often only the larger, fish-bearing streams that are afforded the strongest safeguards. Yet, even without fish, headwater streams and riparian areas are hotspots of biodiversity, and they are the source of much of the water, gravel, and nutrients that subsidize downstream environments. Amphibians, in particular, thrive in the relatively cool and moist microclimate created by headwater streams. In fact, more than a quarter of amphibian species in the region have life histories reliant...

Over the past 7 years, a strong collaboration has emerged between the H.J. Andrews Experimental Forest ecosystem research group and the Spring Creek Project for Ideas, Nature, and the Written Word, an independently funded program for nature writing based in the Department of Philosophy, Oregon State University. The program is called Long-Term Ecological Reflections and it brings together scientists, creative writers, and environmental philosophers to consider new ways to conceptualize and communicate views of long-term ecological change in forests and watersheds and the participation of...

Seeds are the principal means of regeneration of most woody plants. They serve as the delivery system for the transfer of genetic materials from one generation to the next. The part of a tree’s life cycle that involves seed formation, maturation, dissemination, and germination is a complex—yet fascinating—chain of events, many of which are still poorly understood. Yet some knowledge of these events is necessary for successful collection and utilization of seeds to produce the means for artificial regeneration. This chapter presents basic information on the biology of seeds and how this...

For hundreds of years, oaks thrived in many parts of the Pacific Northwest’s lowlands, growing in a variety of conditions and as part of several ecological communities—from dry rock outcrops and wetlands, to prairie edges, grassy savannas, and woodlands. Periodic fires in the region, especially those set by Native Americans, limited the growth of conifers in some places and favored the fire-tolerant oaks.

We examined the short-term separate and combined effects of simulated nitrogen (N) deposition (fertilization) and ozone (O3) exposure on California black oak seedlings (Quercus kelloggii Newb.), an ecologically important tree of the San Bernardino Mountains downwind of Los Angeles. Realistic concentrations of O3 were found to cause statistically and biologically significant negative effects on plant health, including lowered photosynthetic ability, lowered water use efficiency, and increased leaf chlorosis and necrosis. When subjected to abrupt changes in light levels, O3-exposed plants...

Oregonanura cascadensis, a new genus and species of Paranurini from North America is described and illustrated. Taxonomic remarks are given.

The Geoscience Laser Altimeter System (GLAS), a spaceborne light detection and ranging (lidar) sensor, has acquired over 250 million lidar observations over forests globally, an unprecedented dataset of vegetation height information. To be useful, GLAS must be calibrated to measurements of height used in forestry inventory and ecology. Airborne discrete return lidar (DRL) can characterize vegetation and terrain surfaces in detail, but its utility as calibration data for GLAS is limited by the lack of a direct relationship between the canopy height measurements collected by airborne and...

The complex mix of economic and ecological objectives facing today's forest managers necessitates the development of growth models with a capacity for simulating a wide range of forest conditions while producing outputs useful for economic analyses. We calibrated the gap model ZELIG to simulate stand level forest development in the Oregon Coast Range as part of a landscape-scale assessment of different forest management strategies. Our goal was to incorporate the predictive ability of an empirical model with the flexibility of a forest succession model. We emphasized the development of...

As part of the Northwest Gap Analysis Project, land cover maps were generated for most of eastern Washington and eastern Oregon. The maps were derived from regional SAGEMAP and SWReGAP data sets using decision tree classifiers for nonforest areas, and Gradient Nearest Neighbor imputation modeling for forests and woodlands. The maps integrate data from regional vegetation plots with satellite imagery and other geographic information system data, and provide more information than typical land cover maps. Maps also were developed for altered and disturbed land cover classes, and for cover of...