Treesearch

This report summarizes a 1985 timber resource inventory of the non-Federal forest land in the five counties (Coos, Curry, Douglas, Jackson, and Josephine) in southwest Oregon. Detailed tables of forest area, timber volume, growth, mortality, and harvest are presented.

Provides current information on lumber and plywood production and prices; employment in the forest industries: international trade in logs, lumber, and plywood: volume and average prices of stumpage sold by public agencies: and other related items.

Econometric models of changes in land use acreages in the Southeast by physiographic region have been developed by pooling cross-section and time series data. Separate acreage equations have been estimated for the three major private forestland owner classes and the three major classes of nonforest land use. Observations were drawn at three or four different points in time for the 21 Forest Survey Units in the Southeast. Of the variables examined, population and personal income measures were the major significant explanatory variables in the land use equations.

Patterns of branch growth in Pinus contorta Dougl. ex Loud, (lodgepole pine) on the east side of the Cascade Range in Oregon were significantly altered by Arceuthobium americanum (lodgepole pine dwarf mistletoe). There were decreases in the number, length, and mass of needles, as well as in the length and mass of twigs. These reductions were correlated with the infection status of individual branches. Generally, twigs from uninfected branches supported the greatest number, size, and mass of needles, as well as the greatest twig mass. Twigs from branches having localized infections were...

Nitrogen concentration in current year needles of Pacific silver fir (Abies amabilis Dougl. ex Forbes) showed a significant (P

A modification of the macro-Kjeldahl method that provides increased sensitivity was developed for determining very low levels of nitrogen in forest streams and in rain-water. The method is suitable as a routine laboratory procedure. Analytical range of the method is 0.02 to 1.5 mg/L with high recovery and excellent precision and ac-curacy. The range can be increased to include higher levels of nitrogen by dilution of samples at time of Nesslerization, or by using smaller volumes of samples at the start of the analysis.

Interim definitions of old-growth forests are provided to guide efforts in land-management planning until comprehensive definitions based on research that is currently underway can be formulated. The basic criteria for identifying old-growth Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and mixed-conifer forests in western Washington and Oregon and California are given.

Eight species of woodpeckers coexist in conifer forests in northeastern Oregon: northern flicker (Colaptes auratus); yellow-bellied (Sphyrapicus varius) and Williamson's (S. thyroideus) sapsuckers; and pileated (Dryocopus pileatus), hairy (Picoides villosus), white-headed (P. albolarvatus), three-toed (P. tridactylus), and black-backed (P. arcticus) woodpeckers. Tree diameter was the most important factor considered in selection of nest trees by northern flickers, Williamson's sapsuckers, and pileated and hairy woodpeckers. These species partitioned the nest habitat by occupying different...

Radial growth of white fir trees, Abies concolor (Gord. and Glend.) Lindl. ex Hildebr., defoliated almost 30 years ago by Douglas-fir tussock moth, Orgyia pseudotsugata (McDunnough), in the central Sierra Nevada was compared with 22 years of growth prior to the outbreak. There was little difference in growth between the two periods indicating that enhanced growth of defoliated trees after the out-break did not occur as reported for two other California outbreaks. Increment cores also revealed for the first time an even older outbreak, which occurred on the same site in 1906-8.

Nitrogen-fixing bacteria in small mammal droppings are potentially important to forest productivity. As we study this phenomenon, however, we continually find unknowns, such as bacteria that we cannot isolate and purify because we do not know which techniques to use. For example, we have recently observed acetylene reduction in the droppings of the tundra vole (Microtus oeconomus) from St. Lawrence Island, Alaska, but we have failed three times to isolate the responsible bacterium. We hope this note will help stimulate parallel research on use of techniques under various circumstances.