Treesearch

During the 1969 summer a Humboldt State College senior biology student was hired for the Caspar Creek Project. His work emphasized collection of data on insect drop, stream temperatures, and solar radiation. An attempt was made to utilize a sampling regime identical to certain selected previous years which had yielded rather complete data.

Changes in the size composition of spawning bed materials in six coastal streams were monitored for 3 years to determine the effects of logging on the habitat of silver salmon (Oncorhynchus kisutch) and trout (Salmo gairdnerii gairdnerii and S. clarkii clarkii). Four test streams were sampled before, during and after logging. Two streams in unlogged watersheds and the undisturbed upstream section of one test stream served as controls. A variety of stream types in second-growth and old-growth forests was selected for observation.

Two species of dwarf mistletoe were studied: Arceuthobium abietinum (Engelm.) Hawksworth and Wiens and A. occidentale Engelm. Viability of fresh seeds was high and not significantly influenced by year of collection, where collected, or plant from which collected. Temperature affected viability most noticeably. It also significantly affected rate and percentage of seed germination. Longevity of radicles of germinated seeds was inversely proportional to temperatures above 5°C.

Sugar pine and ponderosa pine seedlings in the Sierra Nevada, California, with stems bent by heavy snow loads were photographed the next summer and 10 years later. The photographs show that all trees recovered, leaving no permanent stem crook.

Three methods of applying borax were tested for penetration into stump tissues and for effectiveness in controlling Fomes annosus infection of freshly cut white fir stumps. All borax treatments reduced infection significantly; dry powder was the most effective. The degree of penetration of xylem stump tissue and the effectiveness of control in the three methods tested were directly correlated.

In a group of studies at Swain Mountain Experimental Forest in northeastern California, seedling survival and mortality were analyzed within the general framework of seed production and dispersal, germination, seedbed condition, soil surface temperature, insolation, soil moisture, and vegetative competition. Factors found to favor seedling establishment were abundance of sound seed, mineral soil seedbed, and probably some shade in the first year. Chief obstacles to seedling survival and growth included strong insolation, deep litter, insects, competing low vegetation, and time between good...

During pyrolysis of pure cellulose, the Crystallinity Index (Crl) remained fairly constant over more than 50% weight loss before dropping rapidly as the X-ray pattern deteriorated. With samples first treated with trace quantities of inorganic salts, heating first increased the Crl—the results implying a preferentially catalyzed decomposition of the amorphous regions. Swelling cellulose in liquid ammonia eliminated the crystalline diffraction pattern, but heating restored a considerable degree of order. The initial weight loss rate in the swelled material was considerably accelerated and...

California forest tree seed zones were established originally by Fowells (1946), with revisions proposed by Roy (1963) and Schubert (1966). The Forest Tree Seed Committee of the Northern California Section, Society of American Foresters, has revised the original zones and updated the recording system described in the earlier reports. Fowells' (1946) Research Note should be reviewed for background material. Portions of Schubert's (1966) proposals were incorporated in the new system.

In part to supplement meager data on lumber grade yield of Hawaii-grown timber, 30 robusta eucalyptus logs were shipped to a Michigan sawmill for processing. The logs were from 12 trees in three different stands. The lumber produced was graded according to National Hardwood Lumber Association standards. The sample was too small to provide a basis for predicting grade yields, but robusta yields, by log grade, compared favorably with yields of common hardwoods on the United States mainland.