Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 6 of 6
Full-Text Articles in Physical Sciences and Mathematics
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 …
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.
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.
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 …