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Old Growth Ponderosa Pine And Western Larch Stand Structures: Influences Of Pre-1900 Fires And Fire Exclusion, United States Department Of Agriculture, Forest Service
Old Growth Ponderosa Pine And Western Larch Stand Structures: Influences Of Pre-1900 Fires And Fire Exclusion, United States Department Of Agriculture, Forest Service
Forestry
Presents detailed age structure for two western larch stands that historically experienced frequent fires. Compares age structures of eleven ponderosa pine and western larch stands representing a broad range of sites that had frequent fires. Interprets causal factors possibly linked to variations in stand age structures.
Logging Utilization - Utah, 1993, United States Department Of Agriculture, Forest Service
Logging Utilization - Utah, 1993, United States Department Of Agriculture, Forest Service
Forestry
Data collected on 20 logging operations in Utah in 1993 provided board-foot and cubic-foot conversion factors of log scale and factors to apply to harvest volume estimates to obtain removals estimates. The components of timber products and removals, obtained by application of these factors to the 1992 Utah timber harvest, are included. Additional findings, presented in table form, are the diameter distribution of trees removed from growing stock per thousand cubic ft of products and the volume of logging residue in pieces 6 ft and longer as a proportion of product volume. Survey methods and estimates of data reliability are …
Forest Resource Statistics For Northern Utah, 1993, United States Department Of Agriculture, Forest Service
Forest Resource Statistics For Northern Utah, 1993, United States Department Of Agriculture, Forest Service
Forestry
About 5.2 million acres, or 25 percent, of northern Utah is forested. Fifty-two percent of this forest area is capable of producing commercial wood products and is classified as timberland. Forty-eight percent is classified as woodland, primarily pinyon-juniper. The predominant forest types on the timberland are aspen, Douglas-fir, lodgepole pine, and spruce-fir. The National Forest System manages 70 percent of the timberland; 23 percent is under private ownership, and 7 percent is under other public ownership (local, State, and other Federal). Thirteen percent of the timberland is withdrawn from commercial timber production and is in a reserved status. Most reserved …
Utah Timber Production And Mill Residue, 1992, United States Department Of Agriculture, Forest Service
Utah Timber Production And Mill Residue, 1992, United States Department Of Agriculture, Forest Service
Forestry
Utah's timber production in 1992 was 13.3 million cubic feet (63.7 million board feet, Scribner rule), up 9 percent from 1974. Sawlog production was 10.2 million cubic feet (52.5 million board feet). House log volume was 1.6 million cubic feet (8.2 million board feet). Lodgepole pine comprised 48 percent, Uintah County 29 percent, and National Forest lands 78 percent of the harvest. Mill residue volume was 7 million cubic feet, 82 percent of which was used, most for fencing, firewood, animal bedding, or industrial plant fuel.
Fire-Bgc -- A Mechanistic Ecological Process Model For Simulating Fire Succession On Coniferous Forest Landscapes Of The Northern Rocky Mountains, United States Department Of Agriculture, Forest Service
Fire-Bgc -- A Mechanistic Ecological Process Model For Simulating Fire Succession On Coniferous Forest Landscapes Of The Northern Rocky Mountains, United States Department Of Agriculture, Forest Service
Forestry
An ecological process model of vegetation dynamics mechanistically simulates long-term stand dynamics on coniferous landscapes of the Northern Rocky Mountains. This model is used to investigate and evaluate cumulative effects of various fire regimes, including prescribed burning and fire exclusion, on the vegetation and fuel complex of a simulation landscape composed of many stands. Detailed documentation of the model FIRE-BGC (a FIRE BioGeoChemical succession model) with complete discussion of all model parameters is followed with results of an application of the FIRE-BGC to a whitebark pine landscape in the Bob Marshall Wilderness complex. Simulation results of several management scenarios are …
Managing Lodgepole Pine To Yield Merchantable Thinning Products And Attain Sawtimber Rotations, United States Department Of Agriculture, Forest Service
Managing Lodgepole Pine To Yield Merchantable Thinning Products And Attain Sawtimber Rotations, United States Department Of Agriculture, Forest Service
Forestry
This paper suggests solutions for a longstanding problem in managing lodgepole pine forests -- that of managing individual stands to reach their planned rotation age, despite serious hazard from bark beetles and wildfire. The management regimes presented yield merchantable thinning products. The 80-year sawtimber rotation can be achieved using these management recommendations. Thinning at 30 years of age is central to achieving the recommended alternative management regimes. The authors suggest that agencies give roundwood operators a portion of the thinning stemwood as payment. Management regimes that provide attainable rotations are presented in summary tables, by three site index classes and …
Predicting Regeneration Establishment With The Prognosis Model, United States Department Of Agriculture, Forest Service
Predicting Regeneration Establishment With The Prognosis Model, United States Department Of Agriculture, Forest Service
Forestry
Conifer establishment following regeneration timber harvests is predicted by version 2 of the Regeneration Establishment Model, a submodel of the Prognosis Model. The regeneration model covers 10 species for forests in Montana, central Idaho, and northern Idaho. Most harvest and site preparation methods can be simulated so that alternative treatments can be evaluated. Also included in the model is the influence of western spruce budworm (Choristoneura accidentalis) on regeneration success. The model predicts the probability of stocking, seedling density, species composition, and seedling heights 2 to 20 years after harvest. This paper describes the study design, equation development, model formulation, …
Effects Of Seeder Design And Seed Placement On Seedling Size And Cull Rates At Western Forest Nurseries, United States Department Of Agriculture, Forest Service
Effects Of Seeder Design And Seed Placement On Seedling Size And Cull Rates At Western Forest Nurseries, United States Department Of Agriculture, Forest Service
Forestry
Nursery plots sown with the Summit Precision Seeder and the Oyjord Seeder were compared with plots oversown and hand thinned to desired spacings. We studied 26 seedlots of nine conifer species at five Forest Service, U.S. Department of Agriculture, nurseries. Results varied with nursery, species, and seed characteristics. Thinned plots produced less clumping and fewer gaps between seedlings, but showed little or no difference in seedling size, nor in the number of acceptable seedlings.
A Partial Glossary Of Elk Management Terms, United States Department Of Agriculture, Forest Service
A Partial Glossary Of Elk Management Terms, United States Department Of Agriculture, Forest Service
Forestry
This glossary helps define terms that have been misused during forest planning. Terms that were developed from research on the influences of timber sales and roads during the summer months have been used inappropriately when referring to winter range, hunting seasons, and other conditions. The glossary is based on the results of an "Elk Management Terminology Workshop" held at the University of Montana's Lubrecht Experimental Forest on April 3-4, 1990.
Predicting Equilibrium Moisture Content Of Some Foliar Forest Litter In The Northern Rocky Mountains, United States Department Of Agriculture, Forest Service
Predicting Equilibrium Moisture Content Of Some Foliar Forest Litter In The Northern Rocky Mountains, United States Department Of Agriculture, Forest Service
Forestry
Forest foliage that comprises much of the forest floor litter has higher equilibrium moisture content, EMC, than woody components. The EMC's at 300 degrees K were found to increase as follows: grasses < fir-spruce needles < pine-cedar needles < aspen leaves-larch needles. Equations that express Gibbs free energy associated with moisture content were used to develop regression equations that predict the EMC's from temperature and relative humidity, RH, for temperatures between 278 degrees K (40 degrees F) and 322 degrees K (120 degrees F) and RH's between 10 and 90 percent.
Pine Hollow Exclosures: Effect Of Browsing On An Aspen Community Sprayed With 2, 4-D, United States Department Of Agriculture, Forest Service
Pine Hollow Exclosures: Effect Of Browsing On An Aspen Community Sprayed With 2, 4-D, United States Department Of Agriculture, Forest Service
Forestry
The Pine Hollow aspen (Populus tremuloides) exclosures on the Ashley National Forest in eastern Utah were sampled in 1984, 19 years after they were established. The effects of 2, 4-D, wildlife, and cattle on plant succession were evaluated. Two exclosures were used to protect the sprayed area from (1) all animal use and (2) only livestock use. A third sprayed area was left open for use by all animals. The aspen overstory was killed as a result of spraying, with sufficient reproduction occurring to restock the stand. However, animal use drastically altered the aspen reproduction, as well as the understory …
Incidence Of Compression Wood And Stem Eccentricity In Lodgepole Pine Of North America, United States Department Of Agriculture, Forest Service
Incidence Of Compression Wood And Stem Eccentricity In Lodgepole Pine Of North America, United States Department Of Agriculture, Forest Service
Forestry
Trees 76 mm d.b.h. had higher stem-average percentage of compression wood than those 152 mm or 228 mm d.b.h. Latifolia had less compression wood (5.5 percent) than murrayana (7.7 percent). In both varieties, stem sections from 45° through 50° latitude were proportionally more free of compression wood than sections from other latitudes. Transverse stem sections typically displayed a main body of compression wood opposite an eccentrically located pith. Percentage of compression wood tended to be higher in stems that were out of round and close to ground level, and if pith was eccentric, specific gravity high, and moisture content low. …
Mule Deer Diets On A Chained And Seeded Central Utah Pinyon-Juniper Range, United States Department Of Agriculture, Forest Service
Mule Deer Diets On A Chained And Seeded Central Utah Pinyon-Juniper Range, United States Department Of Agriculture, Forest Service
Forestry
Study of the seasonal use by mule deer of some native and introduced species on a pinyon-juniper restoration project showed that woody species made up the bulk of pellet samples, followed by forbs and grasses. Land managers are advised on seeding and grazing practices for enhancing big game habitats.
Mtclim: A Mountain Microclimate Simulation Model, United States Department Of Agriculture, Forest Service
Mtclim: A Mountain Microclimate Simulation Model, United States Department Of Agriculture, Forest Service
Forestry
A model for calculating daily microclimate conditions in mountainous terrain is presented. Daily air temperature, shortwave radiation, relative humidity, and precipitation are extrapolated from data measured at National Weather Service stations. The model equations are given and the paper describes how to execute the model. Model outputs are compared with observed date from several mountain sites.
Effects Of Prescribed Fire On Biomass And Plant Succession In Western Aspen, United States Department Of Agriculture, Forest Service
Effects Of Prescribed Fire On Biomass And Plant Succession In Western Aspen, United States Department Of Agriculture, Forest Service
Forestry
Biomass of grasses, forbs, shrubs, and aspen suckers was determined annually for three prescribed fires in aspen and aspen-conifer forests in southeastern Idaho and western Wyoming. Fires ranged from low to high severity and overstory mortality from 20 to 100 percent. Over 4 postburn years, production of grasses and forbs averaged 1.5 to 3.3 times that of controls. After 5 years, shrub biomass was 21 to 100 percent of preburn biomass. The varied patterns of seral vegetation and their management implications are discussed.
Evaluating Statistical Techniques For Predicting And Interpreting Forplan Results, United States Department Of Agriculture, Forest Service
Evaluating Statistical Techniques For Predicting And Interpreting Forplan Results, United States Department Of Agriculture, Forest Service
Forestry
Two approaches using multiple linear regression for analyzing the effects of management constraints on an objective function in FORPLAN were tested on three National Forests. The two approaches, ordinary least squares regression and ordinary least squares using principal components, provide some degree of success in predicting objective function values, but very little information for interpreting the effects of the constraints on objective function values.
Container-Grown Ponderosa Pine Seedlings Outperform Bareroot Seedlings On Harsh Sites In Southern Utah, United States Department Of Agriculture, Forest Service
Container-Grown Ponderosa Pine Seedlings Outperform Bareroot Seedlings On Harsh Sites In Southern Utah, United States Department Of Agriculture, Forest Service
Forestry
Reforestation of ponderosa pine (Pinus ponderosa Dougl. ex Laws.) on the lower elevations of the Dixie National Forest in southern Utah has traditionally been challenging. Replanting has often been necessary, costly, and not always successful. Although this problem is not unique, the low levels of available soil moisture during the spring planting season are probably as critical in the Dixie as anywhere in the Intermountain Region. Until this study was initiated, only bareroot seedlings had been planted.
Finding The Appropriate Forage Value For Analyzing The Feasibility Of Public Range Improvements, United States Department Of Agriculture, Forest Service
Finding The Appropriate Forage Value For Analyzing The Feasibility Of Public Range Improvements, United States Department Of Agriculture, Forest Service
Forestry
To complete economic analysis of range improvements completed on the Oak Creek Management area of central Utah, we needed an estimate of the value of forage. A review of the literature revealed several methods of estimating forage values. These methods yielded eight estimates of public rangeland forage ranging from $1.23 to $30 per animal unit month (AUM). Six of the estimates were based on actual market transactions or current administered prices and were the most reflective of actual economic processes. The best estimates of value were those for leasing similar rangeland in the immediate area.
Overstory Removal And Residue Treatments Affect Soil Surface, Air, And Soil Temperature: Implications For Seedling Survival, United States Department Of Agriculture, Forest Service
Overstory Removal And Residue Treatments Affect Soil Surface, Air, And Soil Temperature: Implications For Seedling Survival, United States Department Of Agriculture, Forest Service
Forestry
Timber harvesting and residue reduction practices that alter shade, surface thermal properties, and moisture influence energy balance and heat transfer on the site, significantly influencing temperatures. Because the problems of mortality to seedlings due to high temperature and insufficient moisture are potentially widespread and expensive, it is crucial to be able to identify problem sites during the planning process.
Ranking Thinning Potential Of Lodgepole Pine Stands, United States Department Of Agriculture, Forest Service
Ranking Thinning Potential Of Lodgepole Pine Stands, United States Department Of Agriculture, Forest Service
Forestry
This paper presents models for predicting edge-response of dominant and codominant trees to clearing. Procedures are given for converting predictions to a thinning response index, for ranking stands for thinning priority. Data requirements, sampling suggestions, examples of application, and suggestions for management use are included to facilitate use as a field guide.
Proceedings -- National Wilderness Research Conference: Issues, State-Of-Knowledge, Future Directions, United States Department Of Agriculture, Forest Service
Proceedings -- National Wilderness Research Conference: Issues, State-Of-Knowledge, Future Directions, United States Department Of Agriculture, Forest Service
Forestry
Includes 35 reports giving perspectives on wilderness values, management, and research; states-of-knowledge for wilderness resource research; states-of-knowledge for wilderness user research; and future directions for wilderness research.
Soluble Sugar Concentrations In Needles And Bark Of Western White Pine In Response To Season And Blister Rust, United States Department Of Agriculture, Forest Service
Soluble Sugar Concentrations In Needles And Bark Of Western White Pine In Response To Season And Blister Rust, United States Department Of Agriculture, Forest Service
Forestry
Amounts of soluble sugars in certain tissues of 12- to 16-year-old western white pine (Pinus monticola Dougl.) trees, each with a blister rust canker girdling about 50 percent of the bole circumference, were compared with rust-free trees. Fructose, glucose, sucrose, raffinose, and stachyose extracted from needles and healthy and diseased bark were identified with thin-layer chromatography and quantified with a densitometer. The host's seasonal growth cycle induced changes in sugar concentrations in current, 1- and 2-year needles, but the bole cankers did not. Amounts of bark sugars characterized the activities of the rust fungus (Cronartium ribicola J.C. Fisch.) as well …
'Hobble Creek' - A Superior Selection Of Low-Elevation Mountain Big Sagebrush, United States Department Of Agriculture, Forest Service
'Hobble Creek' - A Superior Selection Of Low-Elevation Mountain Big Sagebrush, United States Department Of Agriculture, Forest Service
Forestry
This is the foundation document for the release of the 'Hobble Creek' selection of big sagebrush. It is a low-elevation mountain big sagebrush (Artemisia tridentata ssp. vaseyana). 'Hobble Creek' is needed to increase the nutrient content of winter diets of mule deer (Odocoileus hemionus hemionus) and domestic sheep (Ovis aries). This sagebrush exceeds the typical winter forage values in amount of energy-producing compounds, crude protein, phosphorus, and carotene. Of the 186 big sagebrush selections tested. 'Hobble Creek' is the most preferred by wintering mule deer and ranks high in preference by wintering domestic sheep. 'Hobble Creek' does not contain substances …
The Influence Of Viewing Angle On Elk Hiding Cover In Young Timber Stands, United States Department Of Agriculture, Forest Service
The Influence Of Viewing Angle On Elk Hiding Cover In Young Timber Stands, United States Department Of Agriculture, Forest Service
Forestry
Young timber stands, even when providing 100 percent visual concealment for elk when viewed on a horizontal plane, may provide 50 percent or less cover when viewed from an opposing slope at an elevated viewing angle. The higher the viewing angle, the greater the relative cover loss. In a simple linear model, viewing angle explained 52 percent of the variation in hiding cover values. Slightly more variation was accounted for when the data were stratified by tree height. On the average, for a 10-degree elevation in viewing angle, hiding cover decreased by 10 percent. The cover loss relationship was most …
Woodland Tree Volume Estimation: A Visual Segmentation Technique, United States Department Of Agriculture, Forest Service
Woodland Tree Volume Estimation: A Visual Segmentation Technique, United States Department Of Agriculture, Forest Service
Forestry
Visual segmentation, a technique for estimating cubic foot volume of woodland tree species, was compared with actual volume measurement. Comparison was made during a forest inventory of pinyon-juniper woodlands in Nevada and Utah. The visual technique's accuracy, its usefulness in developing volume equations, and applicability to volume inventory were studied. This study indicated visual segmentation is not reliable for estimating volume for a single tree. However, a sample of visually estimated volumes proved adequate for developing volume equations. In an application, a bias of 0 to -9 percent of the mean cubic foot volume per acre resulted from summary of …
Response Of Grass Species To Tree Harvesting In Singleleaf Pinyon-Utah Juniper Stands, United States Department Of Agriculture, Forest Service
Response Of Grass Species To Tree Harvesting In Singleleaf Pinyon-Utah Juniper Stands, United States Department Of Agriculture, Forest Service
Forestry
Cover, yield, and nutrient concentrations of grasses were sampled on tree-harvested and nonharvested plots on north, west, and south aspects of a singleleaf pinyon (Pinus monophylla)-Utah juniper (Juniperus osteosperma) stand. Grass cover increased rapidly the first 2 years following tree harvest, but the rate of increase declined over the next 2 years. Grass yield varied among aspects and soil microsites on tree-harvested plots but not on the nonharvested plots where tree competition masked aspect and microsite effects. All grass species had greater yield and greater percentage nitrogen and phosphorus on harvested than on nonharvested plots. Low digestibility of some species …
Costs Of Managing Nontimber Resources When Harvesting Timber In The Northern Rockies, United States Department Of Agriculture, Forest Service
Costs Of Managing Nontimber Resources When Harvesting Timber In The Northern Rockies, United States Department Of Agriculture, Forest Service
Forestry
When National Forest Timber is sold, land managers are required to protect other forest resources such as wildlife, soil and water, and scenic qualities. Measures taken to protect nontimber resources can raise administrative costs, lower the quantity of timber sold, and can reduce stumpage receipts. The costs of sale administration and the reduction in timber harvested can be readily derived from accounting and planning records. But little information is available on how much nontimber resources cost in terms of stumpage receipts. To provide such information, some 187 timber sales were studied on seven National Forests in the Northern Region between …
Applying Height Growth And Site Index Curves For Inland Douglas-Fir, United States Department Of Agriculture, Forest Service
Applying Height Growth And Site Index Curves For Inland Douglas-Fir, United States Department Of Agriculture, Forest Service
Forestry
Methods for estimating both site index and dominant height growth for inland Douglas-fir in the Northern Rocky Mountains are presented and discussed. The methods should be applicable over a wide range of stand conditions because no restrictions were placed on species composition, stand density, spacing, or age structure in the original stem analysis sample. Increased accuracy can be obtained if habitat type is considered, because the shape of the site index curves varied with respect to three major habitat series groupings. Results are summarized in the form of equations, tables, and graphs. Precision curves are used to illustrate the relationship …
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 …