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Predicting Duff And Woody Fuel Consumed By Prescribed Fire In The Northern Rocky Mountains, United States Department Of Agriculture, Forest Service
Predicting Duff And Woody Fuel Consumed By Prescribed Fire In The Northern Rocky Mountains, United States Department Of Agriculture, Forest Service
Forestry
This paper presents numerical relationships of known precision for predicting duff consumption. They were established by assembling and analyzing data from three previous prescribed fire investigations and then testing them against other published data. Fuel loadings by diameter classes that differed among the studies were converted to a common set of diameter classes. The purpose of assimilating data from several studies was to develop predictive models that could be easily used by practitioners and that would apply over a wide range of conditions.
Measurement Of Field Resistance, Rust Hazard, And Deployment Of Blister Rust-Resistant Western White Pine, United States Department Of Agriculture, Forest Service
Measurement Of Field Resistance, Rust Hazard, And Deployment Of Blister Rust-Resistant Western White Pine, United States Department Of Agriculture, Forest Service
Forestry
Three white pine plantations, composed of materials of several levels of resistance from early generations of the blister rust resistance breeding program, were compared on the basis of annual infection and mortality rates. The sites varied in blister rust hazard; resistant materials were consistent in their performance, and the infection data behaved as one would expect if the genetic and environmental assumptions of the simple interest disease progress model were violated. Presumably, the resistant populations violate the genetic assumptions to the extent of their resistance, and any assessment of resistance performance must take into account both environmental as well as …
Release Of A Thinned Budworm-Infested Douglas-Fir/Ponderosa Pine Stand, United States Department Of Agriculture, Forest Service
Release Of A Thinned Budworm-Infested Douglas-Fir/Ponderosa Pine Stand, United States Department Of Agriculture, Forest Service
Forestry
Current and past defoliation by western spruce budworm (Choristoneura occidentalis Freeman) in an 80-year-old predominantly Douglas-fir (Pseudotsuga menziesii var. glauca [Beissn.] Franco) stand thinned to 14 by 14 feet was significantly lower than in a nearby untreated stand of similar age, species, and site conditions. Analysis of periodic radial growth ratios indicated that prior to thinning, Douglas-fir had been heavily defoliated by budworm and growth was seriously depressed. Following thinning, the host leave trees developed dense crowns and 10-year radial growth increased an average of 57 percent: meanwhile, radial growth of nonhost ponderosa pine (Pinus ponderosa Dougl.) increased 38 percent. …
Attaining Visual Quality Objectives In Timber Harvest Areas - Landscape Architects' Evaluation, United States Department Of Agriculture, Forest Service
Attaining Visual Quality Objectives In Timber Harvest Areas - Landscape Architects' Evaluation, United States Department Of Agriculture, Forest Service
Forestry
When management activities such as timber harvest are undertaken on National Forest lands, landscape architects establish plans and guidelines so the project will meet a desired level of visual quality. This visual quality objective (VQO) for a given project is based on forest conditions, topography, and the type of viewing that is anticipated (viewing distance, number and type of visitors, etc.). Although landscape architects provide criteria and guidelines to achieve these visual objectives, there is no direct feedback mechanism with which to monitor the public's reaction or ascertain the extent to which visual objectives are met.
Soil Water And Temperature In Harvested And Nonharvested Pinyon-Juniper Stands, United States Department Of Agriculture, Forest Service
Soil Water And Temperature In Harvested And Nonharvested Pinyon-Juniper Stands, United States Department Of Agriculture, Forest Service
Forestry
Tree harvesting increased soil water content, but the effect diminished over 4 years. The mean increase in soil water content was 2 to 4 percent the first year following harvest and 0 to 3 percent after 4 years. Although tree harvesting released soil water previously used by tree species, other biotic and abiotic demands increased. We speculate postharvest increases in wind and solar energy at the ground surface and increased understory transpiration in part explain the decline in soil water content differences between harvested and nonharvested plots over time.
Effects Of Bifenox, Dcpa, And Napropamide On Ectomycorrhizal Development Of Conifer Seedlings In Central And Northern Rocky Mountain Nurseries, United States Department Of Agriculture, Forest Service
Effects Of Bifenox, Dcpa, And Napropamide On Ectomycorrhizal Development Of Conifer Seedlings In Central And Northern Rocky Mountain Nurseries, United States Department Of Agriculture, Forest Service
Forestry
Postseeding and postgermination treatments with three weed control herbicides (Bifenox, DCPA, Napropamide) at two rates of application caused little reduction of ectomycorrhizal development on 1- and 2-year-old conifer seedlings in Central or Northern Rocky Mountain nurseries. In many cases, herbicide treatment increased ectomycorrhizal development, particularly with DCPA. In general, herbicide treatment effects on ectomycorrhizal development were species and nursery specific.
Pinyon-Juniper Volume Equations For The Central Rocky Mountain States, United States Department Of Agriculture, Forest Service
Pinyon-Juniper Volume Equations For The Central Rocky Mountain States, United States Department Of Agriculture, Forest Service
Forestry
Gross cubic foot volume equations are now available for pinyon-juniper and several other woodland species in Nevada, Idaho, Utah, Colorado, Wyoming, and South Dakota. The volume equations are based on data collected as a subsample of woodland inventories conducted by Federal and State land management agencies. In these inventories, volumes of 4,705 trees were estimated by a visual sampling method.
An Application Of Discrete Optimization For Developing Economically Efficient Multiple-Use Projects, United States Department Of Agriculture, Forest Service
An Application Of Discrete Optimization For Developing Economically Efficient Multiple-Use Projects, United States Department Of Agriculture, Forest Service
Forestry
A discrete version of the continuous joint production model in economic theory is presented for use in designing multiple-use projects and identifying efficient management prescriptions for forest planning. Data requirements are less demanding than the continuous theoretical model, yet some of the more important features are maintained. Models can be formulated graphically or as mixed-integer programming problems that are easily solved via computerized routines.
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 …
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 …
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.
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 …
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.
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 …
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.
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 …
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.
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).
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 …
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 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.
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.
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 …
Effects Of Burning Moist Fuels On Seedbed Preparation In Cutover Western Larch Forests, United States Department Of Agriculture, Forest Service
Effects Of Burning Moist Fuels On Seedbed Preparation In Cutover Western Larch Forests, United States Department Of Agriculture, Forest Service
Forestry
Natural seeding is normally the preferred method of regenerating conifers in the Northern Rocky Mountains (Schmidt and Shearer 1973). Some seedbed preparation is usually necessary for successful natural regeneration. Shade intolerant species such as western larch (Larix occidentalis Nutt.) regenerate best on bare mineral soil.