Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Keyword
Articles 1 - 5 of 5
Full-Text Articles in Physical Sciences and Mathematics
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 …