Treesearch

This paper describes the procedure for developing a specific habitat restoration model. Results of a detailed Least Bell's Vireo (Vireo bellii pusillus) habitat study on the Sweetwater River drainage, San Diego County California, generated the baseline vegetative and habitat data used. Mean percent cover, density, abundance, species composition, and expected mortality rates of vegetation were used to determine the specifications for the restoration design. Mapped nesting plots were used to determine the arrangement of the planting components.

The Kings River Conservation District planted over 1200 plants of 19 riparian species in the first of two phases of a riparian revegetation project in the San Joaquin Valley. To date, tree survival rates vary from 17 to 96 percent among species, with an overall rate of 62 percent. Shrub survival averages 57 percent and ranges from 23 to 73 percent. Factors affecting plant survival include soil quality, irrigation technique, climate, topography, weed competition, gopher and beaver depredation, vandalism, maintenance practices, and budget constraints.

Data on riparian community composition and environmental conditions were collected on over 20 streams in the Sierra Nevada as part of hydropower licensing studies. Over 1,000 samples were analyzed using two-way indicator species analysis (TWINSPAN), to determine riparian dominance types. Ordination techniques were applied to evaluate associations between environmental conditions and community characteristics. Results indicate that at least 15 communities are found in riparian settings at altitudes ranging from 300 to 3000 m on eastern and western slopes of the Sierra Nevada. These communiti...

A base-line analysis and long-term monitoring study of the riparian system along California's Bishop Creek is being conducted to measure the effects that planned increases in streamflow may have on riparian vegetation and associated wildlife. Six sites located in different major physiographic valley types have been selected for study. Biotic, climatologic, hydrologic, geomorphologic, and edaphic response parameters are being measured to evaluate streamflow and riparian vegetation relationships. Biotic parameters being monitored include stand structural parameters, species composition and...

The Santa Clara Valley Water District, located in Northern California, is currently evaluating a pilot riparian revegetation project on a 1.6 ha (4 ac) site adjacent to Coyote Creek in the south San Francisco Bay Area. Specific techniques used during the design, site preparation and installation of 3640 plants (including seed planting locations) are described. This paper reports on the analysis of 1 year's data, comparing the survival of various types of plant materials for each of the 15 native plant species installed. Plant survival is evaluated for portions of the site irrigated by...

Water potential and stomatal conductance are important indicators of the response of vegetation to manipulations of riparian systems. However, interpretation of measurements of these variables is not always straightforward. An extensive monitoring program along the Carmel River in central California, carried out by the Monterey Peninsula Water Management District, provides examples of the complications that can arise in practice.

Two sites on the Sacramento River near Red Bluff and Colusa, California were planted with seven native tree species plus valley elderberry (a shrub) in an effort to mitigate for the loss of woody riparian vegetation from bank protection construction projects in the area. The stateowned environmental easements on terraces on the river side of the levees had been planted unsuccessfully once before, following failure of native species to regenerate naturally. The new (1987-88) effort includes experimental plantings that are considered to represent state-of- the-art techniques. These are...

The failure of a 22-foot-diameter pipe caused an estimated water flow of 40,000 cfs for approximately one hour, which scoured and removed 1.75 million cubic yards of soil and vegetation from Lost Canyon. Mitigation for the damage caused by the pipe failure included reestablishing the lost vegetation. This paper describes the process of reestablishment including the riparian component. Cooperative planning; perseverance in plant acquisition; use of local sources of plants; use of a qualified contractor; and applying ecological principles in planting techniques and maintenance practices...

White alder (Alnus rhombifolia) is a potentially valuable indicator of water stress along California's waterways. Measurements of stomatal conductance, water potential and tissue water relations in conjunction with growth and morphological studies give evidence for the sensitivity of this species to changes in water availability. Potted seedlings and naturally occurring seedlings and trees were monitored during the 1986 and 1987 growing seasons to determine responses to artificial and natural water regimes. Osmotic adjustment provides a mechanism for drought hardening, but the process is...