Treesearch

Thorough evaluation of insect impact on forest stands is difficult and expensive on the ground. In a study of tree damage following Douglas-fir tussock moth defoliation in Modoc County, California, large-scale (1:1,584)70-mm. color aerial photography was an effective sampling tool and took lesstime and expense than ground methods. Comparison of the photo interpretations with a sample ground cruisegave high correlations (0.78 to 0.095) for tree mortality top kill, and an estimate of mortality made from photoswas within 5 cut of the ground cruise estimate.

The allometric relationship, log (y) = a + k•log (x)-where x is one plant organ (e g., dry weight of roots) and y is another (e.g., dry weight of shoot)-was used to study the relative distribution of growth within loblolly pine seedlings. The relative distribution of growth between shoot and roots or among needles, stem, and roots was unchanged by conditions ranging from full sunlight to one-third of full sunlight. There was an indication that the growth of the shoot was inhibited by soil moisture stress to a relatively greater degree than the growth of the roots, as shown by a decrease in...

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.

Abstract - Because stream fisheries are so closely associated with forested watersheds, it is necessary that the streams and forests be managed jointly under a system of multiple use. This requires a knowledge of the interrelationships between these resources to yield maximum returns from both. It is the purpose of this paper to relate logging practices to fish management by ascertaining the effect of logging-road construction on the drop of insects into a stream.

Describes the climatic, edaphic, physiographic, and biotic habitat conditions of the natural range of California black oak (Quercus kelloggii Newb.) and how this tree reproduces, grows, and dies.

Nonproducing acres and unproductive years are both costly to timberland owners. These costs are reduced by restoring timber stocking with minimum delay. The proper prescription for regeneration can insure fast restocking. But the silviculturist prescribes slash disposal, site preparation, seeding, and planting only after he has carefully examined the site environment and diagnosed species' requirements.

A peculiar, low, shrubby, oak-like plant was discovered by Dale Hall in January, 1962, on the Challenge Experimental Forest (which is maintained by the Pacific Southwest Forest and Range Experiment Station, Berkeley) approximately one mile north of Challenge, Yuba Co., California. It was quite unlike any species known to the senior author and did not appear to be a hybrid of any California oak.

Ponderosa pine seed trees left from a previous cutting on the Challenge Experimental Forest, California, were removed in October 1963. Logging costs and production rates were compared with those for a seed-tree cutting on an area nearby. Production rates for seed-tree removal greatly exceeded those for the operation as a whole. Skidding production increased by 38 percent or 1,247 bd. ft. per hour. Components of this net increase were: using pre-existing skid roads (+9 percent), a larger average log volume (+59 percent), and cost of safeguarding regeneration (-30 percent). The cost of...