This report describes initial results of a yarding time study for the Pansy Basin Study, a cooperative research project designed to test the performance of skylines, balloons, and helicopters operating under various conditions of timber and terrain, and over a range of silvicultural and landscape design prescriptions. Observations during the...
Equations are presented for predicting height to crown base (or bole ratio) for fourteen species of trees common to the mixed-conifer zone of southwest Oregon. Nonlinear regression was used to fit a weighted logistic function for each species. The independent variables include height, crown competition factor in larger trees, stand...
Equations are presented that predict individual-tree 5-year diameter growth, outside bark, for 14 tree species in southwest Oregon. The data used to develop the equations came from 19,245 trees sampled from 391 stands in the study area. These equations express diameter growth as a function of diameter at breast height,...
This paper presents equations developed to predict the height to live crown base of six species in the central western Willamette Valley of Oregon. Weighted nonlinear regression was used to fit a separate logistic equation for each species. The predictor variables are total tree height, crown competition factor in trees...
Equations for predicting height from diameter outside bark at breast height (DBH) were generated for 24 tree species in western Oregon. The equations were based on the asymptotic Chapman-Richards function. Because geographic location and site productivity may influence height-diameter relationships, height-diameter measures from 8727 plots were first grouped by site...
Tarif access tables were developed for mountain hemlock [Tsuga mertensiana (Bong.) Carr.] on the Deschutes National Forest in the Central Oregon Cascade Mountains from an equation for cubic-foot volume including top and stump (CVTS). These tables provide access to the comprehensive tree-volume tarif system.
This report supplements Research Bulletin 18 (1975) of the Forest Research Laboratory, School of Forestry, Oregon State University. Bulletin 18 summarized analyses of data for the first field season of the Pansy Basin Study. This Bulletin extends those analyses to the second, and final, field season. Time-study observations during the...
Reliable estimates of plant biomass and leaf surface area are essential for studying primary production, nutrient cycling, hydrology, wildlife management, and fire. This paper presents equations that can be used to make such estimates for most plant species-trees, shrubs, and herbs-dominant in western and central Oregon.' We also document the...
Using existing permanent research plot data, we developed equations for predicting height-to-crown-base (HCB), 5-yr diametergrowth rate (delta D), 5-yr height-growth rate (delta H), 5-yr mortality rate (PM), and the maximum size-density trajectory for Douglasfir and western hemlock in the coastal region of the Pacific Northwest. With the exception of the...