Treesearch

An emergency survey of the 147,000-acre (59,491 hectare), Stanislaus Complex Burn found that large, continuous, land areas were intensely burned, resulting in strongly hydrophobic soils, with potential to yield catastrophic volumes of flood runoff. The potential cumulative effect of greatly increased runoff efficiency on contiguous watersheds threatened serious downstream flooding, instream damages, and loss of upland site productivity. The interdisciplinary team developed a systematic method to evaluate seeding grass as an emergency watershed treatment. The evaluation used site specific...

Watershed response and recovery from a wildfire which burned 95 percent of the Williams Creek watershed in 1979 were monitored. Ground cover reduced to 11 percent by the fire increased to 80 percent by 1983. Grasses seeded for erosion control provided less than 10 percent cover until 3 years following the fire, and no significant difference in ground cover was found between seeded and unseeded transects. The average area of three channel cross sections on Williams Creek increased by 20 percent 4 years after the fire, but had returned to immediate postfire conditions by 1985. Benthic...

Following extensive, natural wildfires on the Siskiyou National Forest in southwest Oregon during fall 1987, numerous rehabilitation measures were applied to severely burned public and private forest watersheds. Treatments were designed to prevent offsite degradation of water quality and fisheries, to minimize soil erosion and productivity losses, and to prevent offsite damage to life and property. Treatments were concentrated along stream channels and on steeply sloping lands prone to erosion and mass wasting. Treatments included aerial and hand sowing of grass and legume seed, 4,130 ha;...

Wildfire has been for millennia a natural component of our western forested wildlands. Its frequency, severity, and effects have varied depending on the specific environment, the type of fire, and the adaptations of the forest biota to fire. The socio-political environment in which these forests exist has had a much more significant impact on public and private policy towards fire than the physical-biological environment. Although ecological criteria are important in technical planning, they will be overshadowed by socio-political criteria in problem definition and solution for the future.

H. annosum was first discovered as a root pathogen of pine in western United States by E. P. Meinecke in 1909. Other early researchers reported it as a root and butt decay of nonresinous conifers in the west. Olson demonstrated its pathogenicity to western conifers and Wagener and Cave described its occurrence and role in the eastside pine forests. In the last 20 years pathologists have become more aware of H. annosum's role as a root pathogen of true fir. The adverse effects of annosus root disease in the Institute of Forest Genetics and Yosemite National Park have helped to call attention...

The Blake Fire burned about 730 ha of mature timber on the west slope of South Fork Mountain in northwestern California. Many steep innergorge and landslide headwall areas burned very hot, killing most large trees and consuming much of the large organic debris in unstable drainages. This created a potential for adverse effects on downstream fisheries from landsliding and the release of sediment formerly retained behind large organic debris. Emergency rehabilitation focused on enhancing channel conditions by falling and bucking downed logs and dead trees and by salvaging dead "high-risk"-tre...

The history of annosus root disease in Europe and the southeastern United States is reviewed in prefacing the focus of this symposium on the disease as it occurs in the western United States. The topic is developed mostly from world literature on the disease published since mid-1970. The occurrence of annosus root disease in both plantations and natural stands of conifers is discussed, with particular emphasis on disease range, host-pathogen variability, and environmental influences. Concluding attention is given tore-examination of the U.S.D.A. Forest Service guidelines for management of...