Treesearch

The usefulness of stand density index (SDI) has been limited by lack of a way to partition its nonlinear expression into additive components to describe the relative stocking of a stand by species or quality classes. In this paper, a linear equation is derived to permit such a partition. A closely related expression for grand fir stocking is given that retains the merits of SDI, but is more nearly proportional to growth of individual trees within a stand. Hence, the partitioning of stocking into components will be more meaningful to the forest manager with this revised form.

The Sundance Fire on September 1, 1967, made a spectacular run of 16 miles in 9 hours and destroyed more than 50,000 acres. This run became the subject of a detailed research analysis of the environmental, topographic, and vegetation variables aimed at reconstructing and describing fire phenomena. This report details the fire's progress; discusses the fire's buildup in intensity, the fuel complex through which it traveled, the wind and other atmospheric variables affecting the fire's behavior; and describes the processes that probably account for the tree breakage and blowdown, the...

This paper summarizes results from several separate but related studies of seeding and planting Engelmann spruce (Picea engelmanni Parry) and lodgepole pine (Pinus contorta Dougl.). The studies were mode in a cutover stand of beetle-killed spruce on the White River Notional Forest in western Colorado. The 50-acre stand was at 10,500 feet elevation on a gentle northwest slope. A dense ground cover of forbs, grosses, and sedges developed after the area was salvaged logged in 1948.

This case study demonstrates the fusion of two discontinuous gullies in the Colorado Front Range and relates storms and flows to the erosion events. In 7 years, only 5 storms produced runoff in a gully system in the Colorado Front Range of the Rocky Mountains. Storm intensities for periods of 10 minutes influenced runoff production; antecedent precipitation was of no benefit to forecast gully flows. Neither the upstream progression of the head cut nor the amounts of net erosion caused by the individual flows could be related to storm parameters. Stability conditions changed with time but...

A growing population is requring more and more products from the land. As demand for beef and other rangeland products increases, so does the need for more intensive management. Stockmen and other managers of private and public rangelands in the West are concerned with stocking the range to restore and maintain satisfactory forage production and quality, soil stability, and livestock production. For economic reasons the rancher grazing cattle on his own land must know how to maintain high forage production and how to produce maximum yields of high-quality beef. The goal of managers of...

Sherman big bluegrass was successfully established by planting into summer-fallowed land with a double-disc, depth-band drill to control seeding depth at 5/8-inch. Planting during July and August into a moist seedbed gave optimum seedling establishment. Weed competition and erosion on the summer-fallowed land was reduced by leaving the ground in rough-plowed condition until immediately before seeding.

Study of interception storage of snow by two species of sapling conifers in northern Idaho revealed that cumulative snow catch follows the classical law of autocatakinetic growth, or [equation - see PDF] where I, is interception storage, e is the interception storage capacity of the tree, e is the base of the natural logarithm, k is a constant expressing the rate of interception storage, P is accumulated snowfall, and Po is accumulated snowfall at the time of most rapid storage( i.e., the point of inflection of the sigmoid curve). Interception storage conformed to the law in five storms in...

Describes an accurate and simple system for taking continuous weight records of sapling-size trees. Measurements obtained using this system have helped in describing the mechanism of interception storage in tree crowns during snowfall.

Four Pinus contorta X banksiana hybrids developed in California were planted on two sites in Montana and one site in Idaho to determine whether they were suited to climate and soils of these three test locations and whether they were superior to Montana lodgepole pine. Height, diameter, crown width, number of branches per whorl, vigor, and survival were measured 5 and 10 years following establishment. Hybrids were well adapted to climate and soils. Most hybrids did not exceed height growth of Montana trees except in Idaho, where Montana trees are not indigenous. A limited test using...

In 1964, Stockstad and Barney published tables that provided conversion factors for calculating local fire danger in the Intermountain area according to fuel types, locations, steepness of terrain, aspects, and times of day. These tables were based on the National Fire-Danger Rating System published earlier that year. This system was adopted for operational use in Forest Service Regions 1 (Northern) and 4 (Intermountain) in 1965. These tables have since been incorporated into operating procedures of several Forest Service Regions and other forest protection agencies.