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Plant moisture stress (PMS) regimes over the summer were determined in planted Douglas-fir seedlings in clearcut and partial-cut blocks on the south slope clearcut, PMS reaches levels that after June could seriously reduce seedling growth. The PMS of the clearcut plots exceed 15 atmospheres at midmorning in June, but partial-cut plots do not exceed this level until September. The greater PMS of the south clearcut plot has not retarded height growth of the Douglas-fir. This is the only plot, however, on which regeneration stocking is not adequate.

Regeneration was studied on a mixed conifer stand on granitic soils on the Klamath National Forest. Six years after logging and hand planting with Douglas-fir, stocking and growth on cutblocks where slash had been broadcast burned was compared with that on similar unburned cutblocks. Conifers were seven times more plentiful on the unburned areas, the average height of the tallest conifer on each plot was nearly twice as great, and the yearly height growth was 27 percent greater. Results suggest that modification of burning policies on this soil type may improve regeneration.

An electronic calculator with trigonometric functions can be used to compute times of sunrise, sunset, or twilight, or time of desired illumination at any location in mountainous terrain. The method is more convenient and versatile, and less cumbersome than using tables. Latitude, longitude, elevation, day of the year (1 to 366), and slope to the horizon at the azimuth of the sun at sunrise and sunset are necessary for the computations. The effects of elevation of the observation point and blocking of the sun's radiation by terrain surrounding the observation point are included in the...

...The Arboretum must be viable...the Arboretum must be dynamic, offering programs, new programs, and repeat programs, to share the knowledge that we have accumulated..." Francis Ching, Director, Los Angeles State and County Arboretum.¹ ¹Excerpt from: Proceedings of a Symposium: The Urban Arboretum in a Time of Crisis. 1972. University to notes which they have taken on previous of Washington Arboretum Foundation.

Mass wasting is the dominant erosional process in most steep-sloped catchments. major mechanism in this process is the landslide (2, 6, 8, 19, 24, 25, 29). In this paper, unless explicitly stated to the contrary, the reference to debris avalanches and other forms of shallow failures

Abstract - Granitic batholiths around the Pacific Ocean basin provide examples of landslide types that characterize progressive stages of weathering. The stages include (1) fresh rock, (2) corestones, (3) decomposed granitoid, and (4) saprolite. Fresh granitoid is subject to rockfalls, rockslides, and block glides. They are all controlled by factors related to jointing. Smooth surfaces of sheeted fresh granite encourage debris avalanches or debris slides in the overlying material. The corestone phase is characterized by unweathered granitic blocks or boulders within decomposed rock....

Lists 2905 publications, with annotations and subject and author indexes, issued during the first 50 years of the Pacific Southwest Forest and Range Experiment Station (formerly the California Forest and Range Experiment Station), headquartered at Berkeley, California.

Pitch pine (Pinus rigida Mill.) seedlings were grown at constant temperatures of either 21 C or 29 C. Photosynthetic temperature and light response curves were determined after 59, 107, and 153 days. Rates of Co2 uptake decreased with age, and the response to changes in light and temperature became less pronounced. Growth temperatures had no effect on the photosynthetic temperature optimum, and populations from Quebec, New Jersey, and Tennessee all had the same temperature optimum and response pattern. For the Tennessee population, growth at 21 C depressed the rate of photosynthesis at all...

Abstract - Continued inclinometer measurements at borehole sites installed in 1964 in northern California suggest that previously reported rates of soil creep are excessively high. Upon analysis of 35 access casings located in forested and grassland sites, no consistent direction of soil movement could be detected. In addition, no significant rate of soil creep could be found for the 8 years in which boreholes were measured. The study emphasizes the importance of obtaining intimate contact between the sides of the boreholes and the access casing, if soil creep measurements are to provide...