Treesearch

The natural hybrid between rock chestnut oak, Q. prinus, and white oak, Q. alba, was named Q. x saulii by Schneider (1904). The nomenclature used herein follows that of Little (1953). Q. x saulii is frequently identified throughout the area of sympatry of the parental species. It has occurred in Vermont, Massachusetts, Rhode Island, New Jersey, Pennsylvania, the District of Columbia, North Carolina, Illinois, and Alabama according to Sargent's Manual (1922) and in Virginia according to Allard (1949).

On March 12, 1969, Dr. Roger A. Barnhart, Leader, California Fishery Unit, agreed to take over Humboldt State College's responsibility for the Caspar Creek Project since Dr. John DeWitt, Project Supervisor, accepted a temporary Peace Corps assignment in Egypt. Dr. DeWitt agreed to write the major portion of the '68-'69 progress report. Unfortunately, Dr. DeWitt's material has been lost, perhaps only temporarily in his move to Egypt. However, the original data is still on file at Humboldt State College. Dr. DeWitt's material consisted of summarized data on solar radiation (pyheliometer and...

Height and age of understory red fir (Abies magnifica A. Murr.) were related to dwarf mistletoe (Arceuthobiilm campylopodum f. abietinum) infection from the surrounding overstory red fir on four National Forests in California. Percentage of trees infected and intensity of infection increased significantly as height of understory tree increased. Age of understory trees appeared to be closely related to infection in only the youngest age class studied.

The insecticide lindane, applied on bark any time of the year, can effectively destroy broods of the western pine beetle. It may also be effective the year round on the mountain pine beetle, the California five-spined ips, and probably other California species of bark beetles. In tests on the Sierra National Forest, lindane sprays formulated at 1.5 percent concentration in diesel oil killed 86.9 to 99.4 percent of western pine beetle broods overwintering in ponderosa pine logs.

Southern California regularly experiences a wind condition known as the Santa Ana winds. This paper describes the phenomenon and the effects it had on fire behavior during the 1966 Loop Fire in the Angeles National Forest, which claimed the lives of 12 fire fighters.

A study made in 1966 in Butte County, Calif., to assess the effectiveness of fire hazard inspection procedures was repeated in 1967. Purpose of the inspections is to secure compliance with fire safety requirements. The observed drop in number of violations suggests a carryover effect in 1967 from the first study. In many cases, personal contact was still necessary to secure conformance--despite exposure to the program in 1966; in some cases, more than one contact proved to be necessary.

Results of U.S. Forest Service research on chemical insecticides suggest that large drops are not as effective as small drops in carrying insecticides to target insects. Two new computer programs have been written to analyze size distribution properties of drops from spray nozzles. Coded in Fortran IV, the programs have been tested on both the CDC 6400 and the IBM 7094 computers. Instructions on their use are included.

In pest control operations by the U.S. Forest Service using malathion sprays, nearly twice as many spruce budworms were killed in Montana as in New Mexico. To find out if budworms in New Mexico had greater tolerance to the insecticide, malathion was applied by topical and aerosol treatments in the laboratory to 6th - instar populations from the two States. No differences in susceptibility of the insects to malathion were found.

Daily progression of shadows cast by red and white fir trees in forest stand openings is illustrated by vertical aerial photographs made on the summer solstice at 2-hour intervals from 7 a.m. to 5 p.m. The aerial photos show shade patterns in three irregularly - shaped, natural stand openings and two different widths (3-chains and 5-chains) of clearcut strips. Illumination measurements are reported to aid interpretation of shadow patterns.