Treesearch

The proceedings is a collection of papers presented at the Symposium on Research and Management of Annosus Root Disease (Heterobasidion annosum) in Western North America held in Monterey, California, April 18-21, 1989. As the first symposium dealing with this subject in the western United States, the papers presented address current research and management issues relating to the topics of biology, ecology, epidemiology, and genetics of Heterobasidion annosum; symptomatology, diagnosis, disease loss, and impacts; factors affecting loss and impact; and management strategies relating to...

A computer program, MIX, was designed to identify pairs of chemicals whose interaction results in a response that departs significantly from the model predicated on the assumption of independent, uncorrelated joint action. This report describes the MIX program, its statistical basis, and instructions for its use.

This personal account of USDA Forest Service activities in Hawaii is from the vantage point of an author who during his two decades there served as the sole Forest Service representative in the Hawaiian Islands, then research center leader, and finally the Director of the Institute of Pacific Islands Forestry. People who served in research and technical assistance capacities, including cooperators from other agencies, and their accomplishments are highlighted. A list of all publications and reports issued during the 20-year period is included.

In the 1950s, timber on steep granitic terrain in Trinity County, California was harvested by using the logging techniques of the time. After Trinity Dam was built in the 1960s, it became evident these techniques were not suited to quality riparian habitat and healthy anadromous fisheries. Since adoption of the Z'berg-Nejedly Forest Practice Act in 1973, efforts have been expended to repair damage that has been done to riparian vegetation, and find forest practices compatible with granitic soils.

Riparian ecosystems have been divided into three basic types; hydroriparian, mesoriparian, and xeroriparian associated in the desert lowlands with perennial, intermittent, and ephemeral water respectively. Floral species associated with these ecosystems can be divided into four categories; obligate, preferential, facultative, and nonriparian. Additionally, various site characteristics such as (1) latitude, (2) elevation, (3) soil, (4) slope, (5) exposure, (6) water periodicity, and (7) water chemistry, create a complex matrix of terms with each one needing delineation. Few of these...

Coyote Creek, along with its associated watershed in Anza-Borrego Desert State Park, is an extremely rich riparian system in the Colorado Desert of California. It provides habitat for the least Bell's vireo (Vireo bellii pusillus), is used as a critical summer watering site for the peninsular bighorn sheep (Ovis canadensis cremnobates), and was the site of major use and encampment by the Cahuilla Indians. Management activities have focused on maintaining or enhancing the integrity of the riparian system. Activities such as eliminating off-highway vehicle use and removing cattle with...

Interrelationships between flooding and climax woody vegetation in riparian ecosystems of the desert Southwest are discussed. The lack of succession in woody desert upland and desert riparian plant communities results from opposite stresses, the former from aridity, the latter from flooding. Today's "wet riparian big five" are northern tree species of hydroriparian and mesoriparian (wet riparian) ecosystems; remnants of the Arcto-Tertiary Geoflora. The "dry riparian big five" are tree or subtree constituents of xeroriparian ecosystems occurring as Madro-Tertiary remnants at the northern...

The Clark Canyon riparian demonstration area was established in 1984 within the East Walker River subbasin of Mono County, California. Destabilization of the meadow sections of the stream and the upper stream reaches contributed to an increase of suspended sediments, turbidity, and stream channel widening in the lower stream reaches where a viable population of rainbow trout is found. Several different treatments have been implemented to (1) restore meadow riparian areas to high levels of productivity, (2) stabilize active erosion and gully development (headcutting), (3) improve aquatic...

Typical cattle use on two range units of hardwood rangeland (annual rangeland) at the San Joaquin Experimental Range, Madera County, California, left 50 percent of riparian area with less than optimum amounts of residual dry matter (RDM) for promoting seedling growth and soil protection. By relocating supplemental feeding sites away from water sources and into areas of high amounts of RDM, the impact of cattle on riparian areas was greatly reduced. In Range Unit 1, where supplemental feeding sites were relocated, only 1 percent of the riparian area was left with low amounts of RDM. In...

The basic tenet of annual range management in California is that perennial grasses are unable to effectively compete with the naturalized alien annual species. Evidence from the field in northern California is not consistent with this thinking. An alternative view that perennial grasses are restricted in importance from overgrazing and excessive rest is presented. Implications for range productivity and stability in riparian zones and uplands are outlined from a rancher's perspective.