Treesearch

Effects of nitrogen, sulfur, and phosphorus fertilizers on growth and nutrient content of Douglas-fir seedlings potted in Grove and Bunker forest soils were determined. Growth was primarily stimulated with nitrogen in the Grove soil and with phosphorus in the Bunker soil. Fertilization influenced nutrient levels in the seedlings. Growth results agree with observed response of Douglas-fir to fertilization in the field where the soils were collected. Data also suggest that low phosphorus and/or high nitrogen may be responsible for lack of positive growth response of Douglas-fir to nitrogen...

The study reviews Hohenadl's procedure for defining form quotients and tree volume from diameters measured at fixed proportions of total tree height. Modifications of Hohenadl's procedure were applied to two sets of data for western hemlock (Tsuga heterophylla (Raf.) Sarg.) from the Pacific Northwest. The procedure was used to define volume differences in thinned stands, and selected form quotients were used as variables to improve accuracy and precision of standard tree volume equations. Estimating form quotients on standing trees requires less time than complete stem dendrometry. The...

The purpose of this study was to develop and validate estimators to predict total crown weight and weight of any segment of crown for old-growth felled and bucked Douglas-fir and western hemlock trees. Equations were developed for predicting weight of continuous live crown, total live crown, dead crown, any segment of live crown, and individual branches for old-growth Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and western hemlock (Tsuga heterophylla (Raf.) Sarg.) trees. A branch method and a ratio method were developed for estimating the weight of crown segments. Equations were...

Data from 1973 and 1980 logging residues studies were used to compare the volume of residue from lump sum and log scale timber sales. Covariance analysis was used to adjust the mean volume for each data set for potential variation resulting from differences in stand conditions. Mean residue volumes from the two sale types were significantly different at the 5-percent level for the 1973 data but were not significantly different for the 1980 data. These inconclusive findings suggest that the relative efficiency of changing sales procedures should be considered before further study is undertaken.

Aerial photo sampling coupled with information taken on the ground provided data for development of estimates of land and forest area by ownership group within the boundaries of the 1971-75 Tanana River Basin timber inventory unit, Alaska. Area of privately owned timberland is estimated at 280,634 acres (113 569 hectares).

Lumber recovery information from 942 logs from old- and young-growth ponderosa pine (Pinus ponderosa Dougl. ex Laws.) trees in northern California is presented. More than 58 percent of the lumber volume was found in 5/4 Shop, Moulding, and Select grades. About 25 percent of the total lumber volume was Moulding, and 24 percent was Standard and Better Dimension. Lumber volume recovery is presented on the basis of cubic feet and board feet. Volume recovery varied by scaling diameter but not by log grade. Value recovery and percent volume by lumber grade did vary by log grade and diameter, but...

Employment and earnings in Georgia's forest products industry, like those of most Southern States, grew significantly between 1970 and 1980. The forest products industry accounted for nearly the same share of the State's economic base in 1980 as in 1970. Moreover, during this period, the State increased its share of the Nation's forest products industry employment and earnings. Pulp and allied products had the highest productivity, but lumber and wood products experienced the largest increase in productivity between 1972 and 1977.

Equations and curves are presented for estimating height and site index of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) on hot, dry sites in the Willamette National Forest in western Oregon. The equations are based on the dissected stems of 27 trees. The curves differ from those previously published for Douglas-fir. Instructions are presented for their use.

Seven silvicultural treatments were applied in a 20-year-old natural western red-cedar (Thuja plicata) Donn ex D. Don) stand on a poor site in coastal Washington: (1) control (unthinned, unfertilized); (2) unthinned, fertilized with ammonium nitrate, monodicalcium phosphate, and potassium sulfate; (3) thinned, unfertilized; (4) thinned, fertilized with urea; (5) thinned, fertilized with ammonium nitrate; (6) same as treatment 5 plus monodicalcium phosphate; (7) same as treatment 6 plus potassium sulfate. Treatments 2 through 7 resulted in significantly better 3-year height and diameter...

A sample of 400 ponderosa pine (Pinus ponderosa Dougl. ex Laws.) trees was selected from each of two sale areas in the Black Hills National Forest, South Dakota. The logs were processed through two sawmills into 1-inch-thick boards. Estimates of volume and value recovery based on cubic volume and board foot volume are shown in tables and figures.