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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.
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.
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.
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 …
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 …
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.
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.
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.
A Hydrologic Model Of Aspen-Conifer Succession In The Western United States, United States Department Of Agriculture, Forest Service
A Hydrologic Model Of Aspen-Conifer Succession In The Western United States, United States Department Of Agriculture, Forest Service
Forestry
Hydrologic impacts of grass-forb to aspen to conifer succession in the Rocky Mountain area are simulated by means of a fundamental model. Model algorithms representing hydrologic processes are sensitive to vegetational changes within the subalpine vegetation zone. Reductions in water yield are predicted as the vegetation on a small Utah watershed proceeds from a grass-forb type to aspen to conifers. Streamflow changes are largely attributable to an interaction between seasonal consumption for each vegetation type and the influence of vegetation type on snowpack. The model synthesizes present understanding and provides a framework for future watershed research.
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.