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Logging cost equations are provided that can be used for analyses of silvicultural regimes. These equations include costs for all phases of logging from felling to loading onto a truck. They are presented by various components so that the user can substitute other values if some components do not seem applicable. Where appropriate these costs vary by size of trees harvested and volume removed at a logging entry. It is especially important that these cost relationships be reflected in logging costs used in evaluations of silvicultural regimes because the evaluations will otherwise be biased...

Site preparation techniques to aid establishment of fourwing saltbush (Atriplex canescens) were compared at a test location in eastern Oregon. Survival and growth of transplanted seedlings were improved after one season of growth by either spot spraying with herbicides or scalping to reduce competing vegetation. Average growth of seedlings was greater with the spray treatment than with scalp treatment. Control of plant competition should improve transplanting success of fourwing saltbush in many related rangeland areas.

This initial study of prescribed burning in ponderosa pine (Pinus ponderosa Doug. ex Laws.) stands in central Oregon showed that all periodic annual growth increments were reduced for trees alive four growing seasons later. Height growth was reduced 8 percent in areas burned by fires with moderate fuel consumption and 18 percent in areas with high fuel consumption. Basal area growth was reduced 16 percent in the moderate fuel consumption areas and 28 percent in the high fuel consumption areas; volume growth declined 23 percent at both levels of fuel consumption. Foliar nitrogen (N)...

The performance of the Bergstrom xylodensimeter, designed to measure the green density of wood, was investigated and compared with a technique that derived green densities from wood disk samples. In addition, log and bole weights of old-growth Douglas-fir and western hemlock were calculated by various formulas and compared with lifted weights measured with a load cell attached to a front-end loader. The Bergstrom xylodensimeter accurately measured green wood density and is useful for estimating log weights.

A sample of 351 ponderosa pine (Pinus ponderosa Dougl. ex Laws.) and 509 lodgepole pine (Pinus contorta Dougl. ex Loud.) logs were used to evaluate the performance of three commonly used formulas for estimating cubic volume. Smalian's formula, Bruce's formula, and Huber's formula were tested to determine which would provide the best estimate of cubic volume when it was applied to tree-length logs. Smalian's formula overestimated the volume by 19 percent, Bruce's formula underestimated by 16 percent, and Huber's formula underestimated by 2 percent. Huber's formula provided the closest...

Multiple regression analyses were used to relate environmental factors to forest regeneration on clearcut and partial cut areas managed by the Bureau of Land Management in the Illinois Valley area southwest of Grants Pass, Oregon. Difficulty of regenerating clearcuttings at elevations between 3,000 and 4,900 feet (914 and 1 494 m) increased with increases in soil coarse fragments, solar radiation, and slash burning. Difficulty of regenerating clearcuttings at elevations between 1,500 and 2,900 feet (457 and 884 m) increased as solar radiation, shrub cover, grass cover, and surface rock...

A simulation model for the development of timber stands in the Pacific Northwest is described. The model grows individual trees of 21 species in a 0.20-hectare (0.08-acre) forest gap. The model provides a means of assimilating existing information, indicates where knowledge is deficient, suggests where the forest system is most sensitive, and provides a first testing ground for hypotheses. Model verification simulations are included for up to 500 years on various sites. Fire, wind, or clearcutting can occur at intervals and intensities specified by users. The model was developed by...

This paper summarizes published reports of deterioration and product recovery studies conducted on dead timber. Decay rates experienced in blowndown timber are presented for western redcedar (Thuja plicata Donn ex D. Don), Douglasfir (Pseudotsuga menziesii (Mirb.) Franco), western hemlock (Tsuga heterophylla (Raf.) Sarg.), and Pacific silver fir (Abies amabilis (Dougl.) ex Forbes). Results from product recovery studies conducted on insect-killed western white pine(Pinus monticola Dougl. ex D. Don), grand fir (Abiesgrandis (Dougl. ex D. Don) Lindl.), Engelmann spruce(Picea engelmannii Parry...

Usable estimates of the mass of live foliage and limbs of sapling and pole-sized ponderosa pine in managed stands in central Oregon can be obtained with equations using the logarithm of diameter as the only independent variable. These equations produce only slightly higher root mean square deviations than equations that include additional independent variables. A better estimate of live foliage mass is produced when distance from breast height to live crown is added. A better estimate of live limb mass is produced with the addition of height. For other components investigated (bole wood...

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.