Treesearch

The symposium, held at Scripps College in Southern California, addressed most aspects of California's vast oak resource. Papers represented four major subject categories: ecological relationships, silviculture and management, damage factors, and products. Both scientific and applied information was presented, including original material not published previously. Individual topics ranged from taxonomy and historical relationships to management of insects and diseases. and various oak products. In California. oaks' value for wildlife, recreation, watershed protection, and esthetics exceeds...

The relationships between 355 wildlife species and their habitats are examined in a series of matrices, life history notes, and distribution maps covering 26 amphibians, 27 reptiles, 208 birds, and 94 mammals. The information is useful in identifying and evaluating the consequences of proposed land management activities-particularly those that manipulate vegetation. Although designed for use by land managers, the publication provides information useful to both professionals and lay persons interested in California wildlife.

This user's guide provides detailed instructions for the use of POLO (Probit Or LOgit), a computer program for the analysis of quantal response data such as that obtained from insecticide bioassays by the techniques of probit or logit analysis. Dosage-response lines may be compared for parallelism or equality by means of likelihood ratio tests. Statistical features of the program, suggestions for the design of experiments that provide data for analysis, and formats for data input and output are described in detail.

Natural dead fuel loading in 62 undisturbed southwestern ponderosa pine stands averaged 21.9 tons per acre, 12.7 tons per acre ≤ 1-inch diameter. Sixteen mixed conifer stands averaged 44.1 tons per acre of dead fuel. Heavy humus loads contributed to loading of 22.2 tons per acre of fuels ≤ 1-inch diameter.

Ponderosa pine (Pinus ponderosa Laws.) was planted at five different spacings, from 6 by 6 to 18 by 18 feet, on a productive site in northern California. Spacing and brush effects on tree growth were evaluated both on plots where brush was allowed to develop and on plots kept free of brush. Competition between trees in brush-free plots began during the 8th year for trees spaced 6 by 6 feet and during the 10th year for trees spaced 9 by 9 feet. On several plots brush competition reduced tree diameters by the equivalent of nearly 3 years growth. These early results forecast the strong...

Continuous monitoring of soil-water pressures, rainfall and runoff under natural conditions was tested as a technique for determining soil hydrologic characteristics of a remote forest watershed plot. A completely battery-powered (and thus portable) pressure transducer–scanner–recorder system was assembled for monitoring of soil-water pressures in the tensiometric range. Measurements during several heavy rainstorms incorporating a period of steady infiltration rate were utilized to determine the saturated (or near-saturated, because of entrapped air) hydraulic conductivities of different...

This hypothesis was tested by a linear programing model: Roadless areas on the Sierra National Forest precluded from planned future development would be candidates for wilderness designation, and the associated loss in present and future timber harvests could be offset by investing in more intensive management. The results of this simulation test suggest that levels of programed harvesting cannot be maintained when roadless areas are withdrawn and funds are reallocated for intensive management on other areas. Additional tradeoffs were found in estimating the effects on fish, wildlife,...

This paper discusses a computer application approach to mapping the scenic boundaries on the Upper Missouri Wild and Scenic River. The approach taken in this effort was the computer program VIEWIT. VIEWIT, for seen area analysis, was developed over an eight-year period prior to 1968, by Elliot L. Amidon and Gary H. Elsner. This is the first attempt by the BLW to utilize this approach on a wild and scenic river. It began and was completed in the summer of 1977.

Analysis of landscape preferences allows the detection of major dimensions as:(1) the opposition between "natural and humanized", (comprising features like vegetation cover, cultivation, pattern of landscape elements, artifacts, excavations, etc.); (2) polarity "precision/ambiguity" (involving opposition between: predominance of straight, vertical lines; contrast; recurrent patterns, etc./curved, diffuse forms, etc.) (3) a polarity "harsh, hostile, awe-inspiring/bland, welcoming" and (4) opposition between warm and cold colors. These trends are not completely independent and a more general...

A numerical model capable of accurately predicting the preference for landscape photographs of selected points in eastern Connecticut is presented. A function of the social attitudes expressed toward thirty-two salient visual landscape features serves as the independent variable in predicting preferences. A technique for objectively assigning adjectives to landscape scenes is also discussed. This Landscape Preference Model has received field application in parts of eastern Connecticut for evaluating the effects of human activities on scenic quality.