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Articles 91 - 120 of 135
Full-Text Articles in Other Earth Sciences
Field Tests Of Elk/Timber Coordination Guidelines, United States Department Of Agriculture, Forest Service
Field Tests Of Elk/Timber Coordination Guidelines, United States Department Of Agriculture, Forest Service
Forestry
During the summers of 1980 and 1981, field validation tests were conducted in 11 different areas in Montana and northern Idaho. The objectives of this research were (1) to evaluate several common methods of determining cover/forage ratios, (2) to evaluate several different road-influence models, and (3) to determine the combination of cover/forage function and road model that best describes actual elk selection among different available habitats.
Crop-Tree Thinning A 50-Year-Old Western Larch Stand: 25-Year Results, United States Department Of Agriculture, Forest Service
Crop-Tree Thinning A 50-Year-Old Western Larch Stand: 25-Year Results, United States Department Of Agriculture, Forest Service
Forestry
This paper describes study results after 25 years of crop-tree thinning in a western larch (Larix occidentalis Nutt.) pole stand in western Montana. Five 1/2-acre plots were established in the Petty Creek drainage, Lolo National Forest, at an elevation of 4,200 feet above sea level. Western larch site index of the study area was 52 feet at 50 years. The stand was 50 years old when the study began in 1949. Two plots were thinned by the D+4 Rule, two by the Crown Rule, and one was left unthinned as a control. After 25 years, periodic diameter, basal area, and …
The Sleeping Child Burn - 21 Years Of Postfire Change, United States Department Of Agriculture, Forest Service
The Sleeping Child Burn - 21 Years Of Postfire Change, United States Department Of Agriculture, Forest Service
Forestry
In early August 1961, more than 26,000 acres (10,500 ha) of upper montane and subalpine forest on the Bitterroot National Forest burned in a lightning-caused wildfire. At the time, the Sleeping Child Burn represented the single largest forest fire in the Northern Rocky Mountains in more than 20 years. Historically, large wildfires have not been uncommon in this region: but after two decades of successful forest fire suppression, the Sleeping Child was treated as an event almost without precedent. Not only was reseeding and rehabilitation an immediate concern, a substantial effort was invested in attempting to return the burned area …
Tree Diameter Measurements At English And Metric Standard Heights: A Comparison, United States Department Of Agriculture, Forest Service
Tree Diameter Measurements At English And Metric Standard Heights: A Comparison, United States Department Of Agriculture, Forest Service
Forestry
The impact of measuring trees at 1.3 m versus 1.37 m heights above ground line was analyzed. The results indicate that the difference in diameter measurement taken at the two points averages around 1 percent. An equation for converting from English diameter at breast height to the metric equivalent of 1.3 m is presented.
Effect Of Small Aspen Clearcuts On Water Yield And Water Quality, United States Department Of Agriculture, Forest Service
Effect Of Small Aspen Clearcuts On Water Yield And Water Quality, United States Department Of Agriculture, Forest Service
Forestry
Streamflow and water quality were monitored in a paired watershed study involving the removal of 20 percent of the aspen (on 13 percent of the area) in five small clearcuts from a 217-acre (88-ha) catchment. There were no significant changes in peak flow, timing, or annual yield during the 4 years of posttreatment monitoring. Significant changes in pH, calcium, magnesium, and nitrates in the snowmelt streamflow from ephemeral subdrainages occurred the second year after cutting. At least some of the differences were attributed to the chemistry of the 1976-77 snowfall, which was also significantly different from snow sampled in the …
Understory Vegetation Inventory: An Efficient Procedure, United States Department Of Agriculture, Forest Service
Understory Vegetation Inventory: An Efficient Procedure, United States Department Of Agriculture, Forest Service
Forestry
The Understory Vegetation Inventory Procedure used on Forest Survey plots provides some basic information about the plant community that, when combined with other information, can be used for wildlife habitat and forage evaluation, grazing use potential, potential climax and seral stage of vegetation, and estimation of land productivity in terms of biomass.
Evaluating Nonindustrial Private Landowners For Forestry Assistance Programs: A Logistic Regression Approach, United States Department Of Agriculture, Forest Service
Evaluating Nonindustrial Private Landowners For Forestry Assistance Programs: A Logistic Regression Approach, United States Department Of Agriculture, Forest Service
Forestry
As budgets in forest management agencies become more restrictive, cost-effective programs become more important. This paper describes a quantitative tool for setting priorities for the forestry assistance program administered by the Montana Division of Forestry. Logistic regression was used to better identify the type of forest owners to which assistance should be directed. (In logistic regression, the dependent variable is a probability that a certain event or activity will occur.) Data supporting model development were obtained from a questionnaire survey of forest landowners in the western portion of Montana. Four models were developed that pertain to past use of technical …
Histological Differentiation Among Abiotic Causes Of Conifer Needle Necrosis, United States Department Of Agriculture, Forest Service
Histological Differentiation Among Abiotic Causes Of Conifer Needle Necrosis, United States Department Of Agriculture, Forest Service
Forestry
Symptoms induced by phytotoxic gases within conifer needles can be differentiated histologically from those caused by other abiotic agents including winter drying, drought, and salt. However, it is not possible to differentiate among symptoms caused by hydrogen fluoride, sulfur dioxide, ethyl mercaptan, and hydrogen sulfide. Phytotoxic gases cause hypertrophy and hyperplasia of vascular parenchyma, endodermis collapse, and intense vascular staining. The other abiotic agents induce mesophyll collapse with little or no observable effects on vascular tissues. Histological analyses should be useful in diagnosis of air pollution-induced injury and damage in coniferous forests.
Production And Product Recovery For Complete Tree Utilization In The Northern Rockies, United States Department Of Agriculture, Forest Service
Production And Product Recovery For Complete Tree Utilization In The Northern Rockies, United States Department Of Agriculture, Forest Service
Forestry
In this study, a whole-tree harvesting system designed to produce logs and chips was evaluated on four sites, each with a different silvicultural prescription. The system consisted of: feller-bunchers, grapple-equipped rubber-tired skidders, a tree processor, a whole-tree chipper, and a hydraulic log loader. Production rates for the overall system and for its various components were developed with time-motion study techniques. Variation in productivity between study areas was analyzed with respect to stand and site characteristics.
Winter Injury Of Sagebrush And Other Wildland Shrubs In The Western United States, United States Department Of Agriculture, Forest Service
Winter Injury Of Sagebrush And Other Wildland Shrubs In The Western United States, United States Department Of Agriculture, Forest Service
Forestry
The objective of this paper is to briefly review winter injury of plants and shrubs in particular, document the observed winter injury of 1976-77, and correlate the occurrence with weather records.
Estimating The Rate And Amount Of Tree Loss From Mountain Pine Beetle Infestations, United States Department Of Agriculture, Forest Service
Estimating The Rate And Amount Of Tree Loss From Mountain Pine Beetle Infestations, United States Department Of Agriculture, Forest Service
Forestry
Because of recurrent depredations by the mountain pine beetle in lodgepole pine, managers have less than a 50 percent chance of growing lodgepole pine to 16-inch diameters in most stands. This paper describes a Rate of Loss Model that estimates the amount of tree and volume loss per year and the longevity of the infestation, and shows how the model can be incorporated into forest planning. The model assumes optimum conditions for the life of an epidemic. However, actual field conditions can cause beetle populations to deviate from predictions causing a bit of overestimation, which is not considered serious in …
Llaffs - A Lightning-Locating And Fire-Forecasting System, United States Department Of Agriculture, Forest Service
Llaffs - A Lightning-Locating And Fire-Forecasting System, United States Department Of Agriculture, Forest Service
Forestry
This publication contains programs and documentation to implement an algorithm for calculating lightning fire probability. This calculation is based on a model originally developed for the National Fire-Danger Rating System. The model algorithm estimates the probability that a lightning discharge from cloud to ground will ignite a fire in fuels at the ground terminus of the lightning. Probability is estimated using variables that are measures of the fuel state and type, rain, and lightning. Details of the model can be found in Fuquay and others (1979), Latham (1979), and Fuquay (1980).
Salvage And Thinning Operations In Second-Growth Ponderosa Pine Stands, United States Department Of Agriculture, Forest Service
Salvage And Thinning Operations In Second-Growth Ponderosa Pine Stands, United States Department Of Agriculture, Forest Service
Forestry
This report describes and discusses a harvesting system made up of commercially available equipment and modified farm tractors that has been successfully used to salvage and thin second-growth ponderosa pine stands. Commercial equipment consisted of fellerbunchers, a skidder, and a chipper. Farm tractors were equipped with grapples and metal reinforcings to adapt them to forest use.
Fireline Production: A Conceptual Model, United States Department Of Agriculture, Forest Service
Fireline Production: A Conceptual Model, United States Department Of Agriculture, Forest Service
Wildfires
This report describes a conceptual model that provides a framework for the components of fireline production. Other conceptual or operational fire-related models may be linked with this production model. Major components and relationships are diagramed.
Flood Insurance Study, City Of Ogden, Utah, Weber County, Federal Emergency Management Agency
Flood Insurance Study, City Of Ogden, Utah, Weber County, Federal Emergency Management Agency
All U.S. Government Documents (Utah Regional Depository)
This Flood Insurance Study investigates the existence and severity of flood hazards in the City of Ogden, Weber County, Utah, and aids in the administration of the National Flood Insurance Act of 1968 and the Flood Disaster Protection Act of 1973. This study will be used to convert Ogden to the regular program of flood insurance by the Federal Emergency Management Agency. Local and regional planners will use this study in their efforts to promote sound flood plain management.
Flood Insurance Study, City Of North Ogden, Utah, Weber County, Federal Emergency Management Agency
Flood Insurance Study, City Of North Ogden, Utah, Weber County, Federal Emergency Management Agency
All U.S. Government Documents (Utah Regional Depository)
This Flood Insurance Study investigates the existence and severity of flood hazards in the City of North Ogden, Weber County, Utah, and aids in the administration of the National Flood Insurance Act of 1968 and the Flood Disaster Protection Act of 1973. This study will be used to convert North Ogden to the regular program of flood insurance by the Federal Emergency Management Agency. Local and regional planners will use this study in their efforts to promote sound flood plain management.
Flood Insurance Study, City Of Harrisville, Utah, Weber County, Federal Emergency Management Agency
Flood Insurance Study, City Of Harrisville, Utah, Weber County, Federal Emergency Management Agency
All U.S. Government Documents (Utah Regional Depository)
This Flood Insurance Study investigates the existence and severity of flood hazards in the City of Harrisville, Weber County, Utah, and aids in the administration of the National Flood Insurance Act of 1968 and the Flood Disaster Protection Act of 1973. This study will be used to convert Harrisville to the regular program of flood insurance by the Federal Emergency Management Agency. Local and regional planners will use this study in their efforts to promote sound flood plain management.
Why Windspeeds Increase On High Mountain Slopes At Night, United States Department Of Agriculture, Forest Service
Why Windspeeds Increase On High Mountain Slopes At Night, United States Department Of Agriculture, Forest Service
Forestry
The purpose of this report is to explain the windspeed increase on mountain slopes at night. Additional work is required to determine such things as the frequency of the winds, the area affected, seasonal variation, and the effect on fire behavior. Also, additional studies are needed to develop the type of procedures required to forecast these nocturnal mountain winds.
Visual Impacts Of Forest Management Activities: Findings On Public Preferences, United States Department Of Agriculture, Forest Service
Visual Impacts Of Forest Management Activities: Findings On Public Preferences, United States Department Of Agriculture, Forest Service
Forestry
A major concern of forest land managers is the visual impact that activities such as timber harvest, road building, and mining have on the forest landscape. Management of the visual resource is a regular part of planning on National Forests, and many other public and private forest land managers are increasing their efforts to protect and enhance this resource. The Forest Residue and Harvesting Research Program at the Intermountain Station includes studies of the impact of harvest and roading activities on visual quality. Preliminary results were reported earlier (Schweitzer, Ullrich, and Benson 1976). This report updates earlier findings and presents …
A Search For Phytotoxins Influencing Germination And Early Growth Of Ponderosa Pine, United States Department Of Agriculture, Forest Service
A Search For Phytotoxins Influencing Germination And Early Growth Of Ponderosa Pine, United States Department Of Agriculture, Forest Service
Forestry
A series of laboratory and field experiments were conducted to determine if mature ponderosa pines produce a substance (phytotoxin) that inhibits the germination and growth of seedlings directly under the tree crown. Neither live nor dead materials collected from ponderosa pines produced either volatile or water-soluble phytotoxins that drastically inhibited germination of seeds or growth of seedlings. Seed overwintering beneath the canopy of mature pine, or planted in soils collected there, showed reduced germination. Exact cause of the reduction was not determined. If weak phytotoxins were responsible, they did not inhibit growth of seedlings that germinated.
Influence Of Some Environmental Factors On Initial Establishment And Growth Of Ponderosa Pine Seedlings, United States Department Of Agriculture, Forest Service
Influence Of Some Environmental Factors On Initial Establishment And Growth Of Ponderosa Pine Seedlings, United States Department Of Agriculture, Forest Service
Forestry
Study plots were established to determine the effects of various environmental factors on ponderosa pine seed germination and initial seedling establishment and growth. A series of soil surface treatments were performed on plots in two locations: within or under the influence of overstory pine trees and in openings away from the pine influence. Seed germination was significantly greater in the opening plots. The overstory canopy and forest floor restricted the amounts of precipitation, light, and heat reaching the soil and probably decreased germination. Cutworms, birds, and small mammals caused the greatest seedling mortality. The largest seedlings occurred in the fire-treated …
Quaking Aspen - Seed Germination And Early Seedling Growth, United States Department Of Agriculture, Forest Service
Quaking Aspen - Seed Germination And Early Seedling Growth, United States Department Of Agriculture, Forest Service
Forestry
The suckering of aspen (Populus tremuliodes Michx.) as a highly effective means of vegetative propagation is well known and has been widely studied (Baker 1918; Day 1944; Maini 1967; Schier 1974). Less is known about seed propagation, sometimes viewed as having only minor importance because early research (Baker 1918) had indicated that rare seedling establishment was due to low or nonexistent germinability.
Nutrient Losses From Timber Harvesting In A Larch/Douglas-Fir Forest, United States Department Of Agriculture, Forest Service
Nutrient Losses From Timber Harvesting In A Larch/Douglas-Fir Forest, United States Department Of Agriculture, Forest Service
Forestry
Nutrient levels as a result of experimental clearcutting, shelterwood cutting, and group selection cutting--each with three levels of harvesting intensity--were studied in a larch-fir forest in northwest Montana, experimentally logged with a skyline system. None of the treatments altered nutrient levels in an intermittent stream, nor were excessive amounts of nutrients lost in soil below the root zone. Under conditions on this site, skyline logging did not result in surface erosion or nutrient losses that would affect forest management.
Sucker Regeneration In A Utah Aspen Clone After Clearcutting, Partial Cutting, Scarification, And Girdling, United States Department Of Agriculture, Forest Service
Sucker Regeneration In A Utah Aspen Clone After Clearcutting, Partial Cutting, Scarification, And Girdling, United States Department Of Agriculture, Forest Service
Forestry
Clearcutting, partial cutting, scarification, and girdling were used to stimulate root suckering in a Utah aspen clone. Regeneration was inventoried yearly during the first 4 years after treatment and again after 12 years. Clearcutting resulted in the greatest number of suckers. In most years, partial cuts (cuts that removed 67 percent of the basal area) had less than 50 percent as much regeneration as the clearcut plots. Girdling stimulated suckering to a lesser degree than cutting. Mortality was high on girdled plots and by the 12th year after treatment few suckers had survived. Scarification had no apparent effect on sucker …
Heat Content Of Bark, Twigs, And Foliage Of Nine Species Of Western Conifers, United States Department Of Agriculture, Forest Service
Heat Content Of Bark, Twigs, And Foliage Of Nine Species Of Western Conifers, United States Department Of Agriculture, Forest Service
Forestry
Comparative combustion tests showed that bark, twigs, and foliage of nine commercial timber species in the Northern Rocky Mountains generally produce more heat than equal volumes of their ovendry wood and that these parts of harvested trees could be profitably utilized as a source of energy.
A Model For Predicting Lightning-Fire Ignition In Wildland Fuels, United States Department Of Agriculture, Forest Service
A Model For Predicting Lightning-Fire Ignition In Wildland Fuels, United States Department Of Agriculture, Forest Service
Wildfires
A model has been developed for predicting the number of lightning-fire ignitions in wildland fuels. The model is based on both stochastic and physical processes. Stochastic methods are used to generalize the lightning storm characteristics and site conditions that affect the potential for ignition. Physical processes are involved in determining the ignition probability of woody fuels by individual lightning events. Input required to operate the model includes lightning activity, upper air windspeed (storm movement), fuel moisture, and fuel bulk density. The model can be used either to predict ignitions at some future time by using forecast data or to estimate …
Fire Behavior In Nonuniform Fuels, United States Department Of Agriculture, Forest Service
Fire Behavior In Nonuniform Fuels, United States Department Of Agriculture, Forest Service
Wildfires
For the purposes of this study, nonuniform fire behavior is predicted by modeling fire spread through a hexagonal network of fuel cells. Fire spread is assumed to be a process of contagious growth between cells. Fuel properties are allowed to vary from cell to cell in a prescribed manner but have uniform properties within the cell. Consequently, the nonuniformity of the actual fuel array is simulated through cell to cell variations and has a resolution limited by the cell size. Because of the nature of the modeling process, it is necessary to devise a scheme for collecting data describing nonuniformity …
Fire - Decay: Interactive Roles Regulating Wood Accumulation And Soil Development In The Northern Rocky Mountains, United States Department Of Agriculture, Forest Service
Fire - Decay: Interactive Roles Regulating Wood Accumulation And Soil Development In The Northern Rocky Mountains, United States Department Of Agriculture, Forest Service
Wildfires
Decay and fire play interactive roles in recycling wood and other organic materials in forest ecosystems, and contribute to the development of high quality soils in the Northern Rocky Mountains. Decayed wood, charcoal, and other decomposed organic matter are the principal media for ectomycorrhizal and nonsymbiotic nitrogen fixing microbes. The activities of these microbes are critical to the growth of forest trees. The balance between decay and fire, as it affects the amount, distribution, and type of organic matter, controls the ability of forest soils to support the growth of trees.
Autecology Of Selected Genera Of Mississippian, Permian And Triassic Ammonoids: Analysis Of Coiling Geometries, Edward Ellis Chatelain
Autecology Of Selected Genera Of Mississippian, Permian And Triassic Ammonoids: Analysis Of Coiling Geometries, Edward Ellis Chatelain
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Ammonoids were collected from the Chainman Formation (Mississippian) of southeastern Nevada and southwestern Utah, the Phosphoria Formation (Permian) of southeastern Idaho and westernmost Wyoming, and the Thaynes Formation (Triassic) of northeastern Nevada and southeastern Idaho. The collections are interpreted to represent unwinnowed, untransported death assemblages of ammonoids which were subject to chemical conditions of the nekto-benthic environment. Associated lithologies were sampled and geochemically analyzed for content of phosphate and organic matter. Ammonoid fossil collections, combined with ammonoids illustrated in the literature, were subjected to the graphical W and D analysis of Raup (1967). The basic parameters involved in the description …
Grazing On National Forest System Lands: Cost Of Increasing Capacity In The Northern Region, United States Department Of Agriculture, Forest Service
Grazing On National Forest System Lands: Cost Of Increasing Capacity In The Northern Region, United States Department Of Agriculture, Forest Service
Forestry
Sample grazing allotments on Ranger Districts in the Northern Region (USDA Forest Service) were surveyed by questionaire to determine the feasibility of increasing grazing capacity through additional range improvements. The survey included an inventory of existing grazing capacity and the specific kind and cost of proposed improvements. Costs of improvements were amortized and aggregated for each Forest Service Planning Area. The resulting costs were compared with the increased grazing capacity measured in animal unit months (AUM) to determine the cost per additional unit of capacity.