For the past ten years, Douglas-fir on the Oregon and Washington coast has shown a progressive decrease in height and diameter increment as a result of Swiss needle cast, which is caused by Phaeocryptopus gaeumannii. In this contribution, we discuss the effects of silvicultural operations on Swiss needle cast and...
Oregon State University researchers conducted a survey in 1994 of non-industrial private forest (NIPF) landowners in western Oregon and western Washington. Private forests provide valuable ecological services, such as fish and wildlife habitat, and are also partially filling the gap created by recent reductions in federal timber harvest in the...
Equations for predicting tree height as a function of diameter outside bark at
breast height are presented for various tree species common to southwest
Oregon. Data for damaged and undamaged trees were analyzed with weighted
nonlinear regression techniques. The effects of specific damaging agents and
their severity on the height-diameter...
This paper comprises two major sections. In the first, tests of the influence of several application factors on efficiency of silvicultural herbicides are described for evergreen shrub, deciduous shrub, and herbaceous forest vegetation in Oregon and California. The second presents decision trees illustrating how to use the experimental results and...
Untreated and preservative-treated fence posts were exposed in soil at a test site near Corvallis, OR. Several species, including western juniper and Osage-orange, showed exceptional natural durability. Preservative treatment generally extended the useful life of the posts, but the degree of protection varied with the chemical and the application method.
Three equations for predicting tree height as a function of diameter (outside
bark) at breast height are presented for six species found in coastal regions of
the Pacific Northwest. Foresters can use these “height–diameter” equations
to avoid the time-consuming task of measuring heights of all individual trees
in an inventory,...
This publication is aimed at watershed councils, government agencies, and specialists (foresters, wildlife and fisheries biologists) interested in riparian area silviculture or watershed restoration. It contains information on the ecology of riparian forests and a checklist of recommended practices and common mistakes made in restoring conifers to hardwood-dominated riparian forests....
Work-study guidelines were developed using field data from thinning sites in the Oregon Cascade Range. Regression of detailed time study and shift-level data predicted harvesting production rates. Statistical analysis showed the relative difference in the discriminating power between shift-level studies versus detailed time studies. Indicator variables tested if there were...
Naturally durable woods have a variety of commercial uses. Natural resistance to decay has been evaluated in field and laboratory tests of wood from many species, but there are few places where commercial wood users can find comparative assessments of natural durability. In this report, previous studies have been used...
Production rates and costs for skyline harvesting were examined over a range of residual thinning intensities, operational methods, and sites. The sites included three stands of 40- to 50-yr-old Douglas-fir on the Willamette National Forest in the Cascade Mountains of Oregon. Three silvicultural treatments were studied at two sites, and...