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Full-Text Articles in Other Earth Sciences
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.
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 …
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. …
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.
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.
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 …
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. …
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.
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 …
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 …
Timelag And Equililbrium Moisture Content Of Ponderosa Pine Needles, United States Department Of Agriculture, Forest Service
Timelag And Equililbrium Moisture Content Of Ponderosa Pine Needles, United States Department Of Agriculture, Forest Service
Forestry
The ponderosa pine (Pinus ponderosa Laws.) timber type covers nearly 9 million acres in the Rocky Mountains. The needle litter cast by these trees produces a highly flammable fuel when conditions are dry. The capability for fires to start and spread depends largely on the moisture content of surface fuels and their response to environmental changes. This report summarizes the results of laboratory tests to determine equilibrium moisture contents and absorption-desorption timelags below fiber saturation of ponderosa pine needles. Conducting the tests at conditions below fiber saturation eliminated consideration of the movement of free water and possible leaching of the …
Low-Cost Harvesting Systems For Intensive Utilization In Small-Stem Lodgepole Pine Stands, United States Department Of Agriculture, Forest Service
Low-Cost Harvesting Systems For Intensive Utilization In Small-Stem Lodgepole Pine Stands, United States Department Of Agriculture, Forest Service
Forestry
The study reported here had two objectives: (1) examine the feasibility of using inexpensive skidding equipment in a small-stem lodgepole pine stand in western Montana, and (2) determine forest residues volumes (unused wood) resulting from different ground skidding methods and utilization standards. Preharvest volumes, volumes removed, residues left on the ground, and unusable material hauled from the site were determined for various utilization standards. The efficiency of skidding with a horse, small tractor, and small rubber-tired skidder were compared.
Genetic Variation In Susceptibility Of Western White Pine To Needle Blight, United States Department Of Agriculture, Forest Service
Genetic Variation In Susceptibility Of Western White Pine To Needle Blight, United States Department Of Agriculture, Forest Service
Forestry
Ten clones of western white pine differed in their susceptibility to white pine needle blight. Two clones were significantly less infected than the average and two clones were significantly more infected than the average. This variability suggests a simple inheritance, maybe just one or two genes.
Estimating Merchantable Volume And Stem Residue In Four Timber Species: Ponderosa Pine, Lodgepole Pine, Western Larch, Douglas-Fir, United States Department Of Agriculture, Forest Service
Estimating Merchantable Volume And Stem Residue In Four Timber Species: Ponderosa Pine, Lodgepole Pine, Western Larch, Douglas-Fir, United States Department Of Agriculture, Forest Service
Forestry
Presents tables and equations for estimating total cubic volumes of wood, wood residue, and bark for ponderosa pine, lodgepole pine, western larch, and Douglas-fir. Tables represent second-growth trees 80 years old or less, ranging in size from 1-1/2 inches d.b.h. to the maximum diameter measured for the respective species. The equations and tables provide a means for estimating wood bark residue volumes from tops, bole sections, and smaller submerchantable stems. Tables and equations can also be used to estimate total cubic volume for the size classes, species, and locale sampled.
Regeneration And Early Growth On Strip Clearcuts In Lodgepole Pine/Bitterbrush Habitat Type, United States Department Of Agriculture, Forest Service
Regeneration And Early Growth On Strip Clearcuts In Lodgepole Pine/Bitterbrush Habitat Type, United States Department Of Agriculture, Forest Service
Forestry
Establishment and growth of seedlings 13 years after strip clearcutting was investigated on a lodgepole pine/bitterbrush habitat type in southwestern Montana. Ingress of new seedlings (all from open-coned lodgepole pine) on areas that had been heavily bulldozer scarified was considerably better than on areas without bulldozer scarification. Seed:seedling ratios (established seedlings) ranged from 625:1 to 2,160:1 on scarified sites, and from 1,876:1 to 6,480:1 on unscarified sites. Only 3 years out of 13 resulted in significant numbers of seedlings being established. Advanced regeneration released by logging was growing as rapidly as seedlings established following logging.