Treesearch

Called "the most princely of the genus" by its discoverer, David Douglas, sugar pine (Pinus lambertiana) is the tallest and largest of all pines, commonly reaching heights of 53 to 61 m (175 to 200 ft) and d.b.h. of 91 to 152 cm (36 to 60 in). Old trees occasionally exceed 500 years and, among associated species, are second only to giant sequoia in volume. For products requiring large, clear pieces or high dimensional stability, sugar pine's soft, evengrained, satin-textured wood is unsurpassed in quality and value. The huge, asymmetrical branches high in the crowns of veteran trees, bent...

Foresters often need information on the cost effediveness of manual and chemical release treatments for individual and combined species in young mixed-shrub communities. A study in northern Califomia evaluated five manual and chemical treatmcnts and their effect on several shrubs and grasses. Treatments were grubbing at age 1 to 2- and 4 ft (0.6- and 1.2-m) radii, regrubbing and expanding the 2-ft radii to 4 ft, regrubbing and expanding the 4-ft radii to 6 A (1.8 m) at age 4, and applying Velpar herbicide to the entire plot at age 2. Five years after initial manual release and 4 years...

The dry-weight-rank method of estimating botanical composition on California's annual grasslands is a viable alternative to harvesting and sorting or methods using points. Two data sets of sorted species weights were available. One spanned nine years with quadrats harvested at peak of production. The second spanned one growing season with 20 harvest dates. Two existing sets of coefficients for the first, second, and third ranked species and one calculated from our data were used to estimate dry-weight composition. We tested the differences between the estimates and actual values. Difference...

In forestry the importance of genetic variation for successful reproduction, survival and growth has been widely documented for commercial conifers; until recently, little genetic work has been done on the California oaks. Even before the nature of genetic variation was scientifically investigated, its importance was suspected in operational forestry. Many failures of commercial plantations were traced to the use of seedlings that, although of native species, were derived from populations distant from the planting site. Similarly, in areas that were regenerated with planted seedlings...

The symposium from which the papers in this issue derive was organized to foster an awareness among forest managers of the issues surrounding biological diversity. Forest geneticists have been calling for conservation of diversity for many years (Anonymous, 1975). Since they were geneticists, they naturally called this gene conservation. Forest geneticists often sold gene conservation from a practical viewpoint. Genes were needed in breeding, as raw material for selection, and to maintain viable populations of commercial species. That argument is as valid as ever, but over time we have...

We report on an intensive research effort to determine the present status of the marbled murrelet (Brachyramphus marmoratus) in the vicinity of Redwood National Park, in Del Norte and northern Humboldt Counties, California. This seabird is primarily an inhabitant of the nearshore waters and adjacent coastal redwood forests of the northern half of the state. Little is known of its ecology on land. Using remote sensing techniques, we mapped all old and mature forests, the potential habitat for the species. We then conducted systematic surveys of stands selected from the above inventory,...

Considerable public criticism and sometimes legal obstructions have been directed toward landscape management in relation to the extraction of natural resources. Many managers do not understand public concerns for visually attractive resources. Managers need to know when landscape alterations, like clearcuts, attract public attention and become visually objectionable. A study assessed the opinions of groups of people, representing various organizations, using color slides to simulate views of managed and natural landscapes. Of 63 management actions, 43 were not detected by more than half...

The use of mulches as a reforestation tool in Oregon and California began primarily in the late 1950's. Many types of mulches were tried including sheets of plastic, newspaper, and plywood; various thicknesses of bark, sawdust, sand, and straw; sprayed-on petroleum resin; and even large plastic buckets. Most proved to be ineffective, costly or both. Early trials tended to use small, short-lived materials that aided conifer seedling survival, but not growth. Compared to other weed-control techniques available at the time, mulches were rather expensive. Current trends are to apply longer-live...

This report summarizes each of 68 ecological surveys conducted from 1975 through 1988 on candidate and established Research Natural Areas in the Pacific Southwest Region of the USDA Forest Service. These surveys represent an important but largely unknown contribution to the ecological literature of California. For each summary, information on location, target elements, distinctive features, physical characteristics, association types, plant diversity, and conflicting impacts is provided. Comparisons are made between similar vegetation types at different sites. Tables and appendices...

The perception of mangroves by people in the Pacific islands and throughout all the world has changed in the past decades. Today, the economic, social, ecologic, and esthetic values of mangroves are well recognized. Past research on these ecosystems is responsible for the change in perception. However, a review of eleven subjects relevant to the management of Pacific mangrove forests revealed numerous gaps in quantitative understanding of man-grove functions and values. These gaps must be filled if the gains in public perceptions of mangrove values are to be institutionalized through...