Treesearch

One-year-old western hemlock (Tsuga heterophylla (Raf.) Sarg.) seedlings from three open-pollination families from eight locations in the Washington and Oregon Coast Ranges were cultured under accelerated growth conditions in a glasshouse. Forty cuttings from each of five seedlings (open-pollination siblings) per family were then placed in a rooting box in a randomized block design with five replications. Percentages of cuttings rooted after 1 year in the bed were analyzed in a hierarchal design. Average rooting percentage was 72.4 percent. Significant effects were associated only with...

Low-elevation seeds collected 6 and 2 weeks before assumed natural seed fall were stratified 1, 2, 4, 8, 16, 32, 64, and 123 days and germinated in the laboratory. Germinated seeds from all stratification periods were sown at the same time in the nursery bed. Germination and seedling measurements were taken over two growing seasons. Early collection gave smaller seeds, reduced germination percentage, and yielded smaller seedlings. Reduced seedling size appeared to be related to reduced seed weight. Germination rates of both early- and late-collected seeds increased with increased stratifica...

The 2- and 5-year diameter and height growth of suppressed grand fir (Abies grandis (Dougl. ex D. Don) Lindl.) advance reproduction was measured in central Oregon after the overstory was removed. Multiple regression analyses were used to predict growth response as a function of individual tree variables. The resulting equations, although highly significant, explained only 17 to 44 percent of the variation in growth. Live crown ratio gave the best single variable correlation for both diameter and height growth. Height growth after release was similar to growth before release. Only vigorous...

These guidelines provide the land manager with procedures for making local supplements to General Technical Report PNW-105, "Photo Series for Quantifying Natural Forest Residues in Common Vegetation Types of the Pacific Northwest"; the process used to photograph and measure residues and summarize the data is described.

A 20-percent reduction in evapotranspiration as measured by a 20-cm increase in soil water content is expected to result in an insignificant increase in streamflow by clearcut lodging in the study area.

Lumber recovery, lumber grade distribution, and log values are presented for logs cut from dead and live Engelmann spruce (Picea engelmannii Parry ex Engelm.) trees. The dead sample includes standing and down trees killed by the Engelmann spruce beetle (Dendroctonus ruffipennis Kirby) over 20 years ago.

Cis-11-tetradecenal was found to be the specific attractant for adult male large aspen tortrix, Choristoneura conflictana (Walker), populations in quaking aspen, Populus tremuloides Michx., forests of interior Alaska. The attractant was dispersed from polyethylene caps in Pherocon® -2 traps placed 1.5 m above ground.

Equations are given for estimating merchantable volumes of second-growth Douglas-fir stands to specified breast-high and top-diameter limits, in cubic feet or board feet, from total volume in cubic feet and certain associated stand characteristics.

Effects of two successive postseason deer hunts on deer browsing of Douglas-fir seedlings in the Coast Range in western Oregon were evaluated. Terminal browsing was significantly lower on the area subjected to more hunting compared with other areas.

The Maybeso Creek valley was logged from 1953 to 1960. Stream maps showing large accumulations of debris and stream channel features were made in 1949 and updated to 1960. The objectives of this paper are to document the effects of natural and logging debris on channel morphome try and to examine the fate of logging debris during and after logging. Map sections from 1949 through 1963 are examined and compared with a ground survey in 1978 of debris accumulations. Natural conditions before logging revealed sparse accumulations of large debris scattered throughout the stream; these accumulatio...