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This publication presents a Landscape Design and Analysis Process, along with some simple methods and tools for describing landscapes and their function. The information is qualitative in nature and highlights basic concepts, but does not address landscape ecology in great depth. Readers are encouraged to consult the list of selected references in Chapter 2 if they wish a more extensive background.There are many unanswered questions about how landscapes operate as ecological systems. Those who attempt to carry out the Landscape Analysis and Design Process should expect to identify a number...

Variation in speed of seed germination was investigated among ponderosa pine trees representing 225 locations in central Oregon. Results suggested that at least some of the geographic variation is related to the severity of summer drought. In general, germination speed was greater in locations with shod, drought-limited growing seasons. Levels of geographic variation were highest in the region having the steepest precipitation gradients. Most of the variation occurred, however, within locations.

Grade-specific price projections were developed for Douglas-fir, coast hem-fir, inland hem-fir, and ponderosa pine lumber. These grade-specific price projections can be used in evaluating management practices that will affect the quality of saw logs produced under various management regimes.

Unrecognized genotype x environment interactions (g,e) can bias genetic-gain predictions and models for predicting growth dynamics or species perturbations by global climate change. This study tested six sets of families in 10 plantation sites in a 78-thousand-hectare breeding zone. Plantation differences accounted for 71 percent of sums of squares (15-year heights), replications an additional 4.4 percent, families 1.9 percent, the first principal component of interaction effects 3.5 percent, and the second principal component 1.2 percent. Results in this study and in a larger survey (87...

Forest inventory data collected in 1987 fTom sample plots established on the Kenai Peninsula were analyzed to provide point-in-time estimates of the trend and current status of a spruce beetle infestation. Ground plots were categorized by stage of infestation. Estimates of numbers of live and dead white spruce trees, cubic-foot volume in those trees, and areal extent of infestation were developed and are presented for each stage of infestation.

A hierarchical classification system separating stream habitat into habitat units defined by stream morphology and hydrology was used in a pre-enhancement stream survey. The system separates habitat units into macrounits, mesounits, and micro- units and includes a separate evaluation of instream cover that also uses the hierarchical scheme. This paper presents an application of the system to a pre-enhancement survey of habitat and salmonid populations. Application of this method accompanied by snorkel counts of fish allowed us to determine habitat area, salmonid densities within habitat...

Morphology and distribution of salmonid habitats were related to the geomorphology of a river basin at three spatial scales including reach (l02-103 m2), subbasin (2-26 km2), and the watershed (240 km2). Stream reaches on a young fluvial terrace (1700 yr old) adjacent to the main river contain the most extensive areas of rearing and spawning habitats. In tributary subbasins, the area of spawning habitat varies according to discharge rates and channel gradients. The most extensive salmonid habitats are located along wide glacial deposits in geologically unconstrained areas of the main...

A study was undertaken to develop methods for extensive inventory and analysis of wildlife habitats. The objective was to provide information about amounts and conditions of wildlife habitats from extensive, sample based inventories so that wildlife can be better considered in forest planning and policy decisions at the regional scale. The new analytical approach involves identifying habitats present on field plots, estimating area present in each habitat condition, and linking the habitat classifications with wildlife-habitat relationship models to describe habitat suitability for...

Potential Problems With Q-Values Many ponderosa pine stands have a limited number of size classes, and it may be desirable to carry very large trees through several cutting cycles. Large numbers of trees below commercial size are not needed to provide adequate numbers of future replacement trees. Under these conditions, application of stand density index (SDI) can have advantages over the use of Q-values in defining stocking levels. Calculation of SDI for uneven-aged stands must be done by summing values for individual trees or diameter classes. An example using SDI to derive stocking...

The aggregate timberland assessment system is a time-based deterministic timber projection model. It was developed by the USDA Forest Service to address broad policy questions related to future timber supplies for the 1989 Renewable Resources Planning Act timber assessment. An open framework design allows for customizing inputs to account for regional and subregional growth and yield characteristics, predictions of change in land use, assumptions of future timber management practices, and projections of future demand for stumpage. As inputs, timberland inventories are aggregated into...