Treesearch

Presented in this Research Note are form-class tables for estimating the volume in board feet, Scribner Rule, of ponderosa pine, Douglas-fir, and white fir in California. This single series of tables fits all three species within acceptable limits of error. It is hoped that this series may satisfactorily replace the many existing tables for single species, both old growth and young growth, and for various sites. The wider application of sales by tree estimates in the national forests of California raises the need for more accurate volume tables. Those now available are based on the two...

Presented here are form-class volume tables giving the volume in board feet, Scribner Rule, for sugar pine and red fir in California. These tables complement the previously published form-class tables for ponderosa pine, Douglas-fir and white fir. The two sets of tables should provide more accurate estimates of individual tree volumes for five of the most important commercial species in California. Much of the text material presented in Research Note 60 has been repeated here in the interest of completeness.

Damages from floods and erosion have been a serious problem in southern California since early pioneer days. The problem is becoming even more serious as the rapidly increasing population and expanding industrial and agricultural development encroach upon the flood plains and extend up the steep slopes and into canyons of the nearby mountains. Protection of forest vegetation from fire is an extremely important factor in maintaining damages at a minimum. The removal of the vegetative cover of the mountain watersheds by fire greatly increases the flood peaks and erosion rates with a consequen...

Immature or unripe seed may be one cause of the poor germination of sugar pine occasionally experienced in nursery practice or direct seeding projects. Ripeness of pine seed, or the time to harvest cones, is usually judged by a change from green to brown in the color of cones or by the development of a firm consistency in the endosperm. However accurately these criteria may be applied, they are subjective and cannot be described well enough to permit consistency in their use. This paper describes an index of ripeness for sugar pine seed.

Propagation of conifers by rooting of cuttings is an old art that has recently benefited by the findings of the plant physiologist. The forest tree breeder may now use rooting as a tool in his efforts to evaluate the heredity of his trees. In a study undertaken to use vegetative propagation of members of a variable hybrid population as a guide for selecting superior individuals, the authors found that wide differences occurred in rooting ability among members of the population, and that in general the differences corresponded in two successive years.

The Eddy Arboretum at Placerville, California, contains more than 90 species, varieties, and hybrids of pines, and is therefore of great interest to horticulturists. The Arboretum was established in 1925 as a source of breeding stock for the Eddy Tree Breeding Station, founded in the same year by Mr. James G. Eddy of Seattle. In 1934 Mr. Eddy presented the Arboretum and Station, now called the Institute of Forest Genetics, to the people of the United States. and the U.S. Forest Service carries on the program of tree breeding.

The temperature profile of a mature forest seldom has been observed. Temperatures at specific locations are of interest to the forester because they may help explain many phenomena, such as growth or death of seedlings and freezing of terminals and floral parts of trees. The opportunity to combine a vertical succession of such temperature measurements into a temperature profile was afforded the author by a battery of thermometers installed in a study of natural regeneration at the Stanislaus Branch of the California Forest and Range Experiment Station. This branch station is located on the...

During the past few years, the Institute of Forest Genetics has received an increasing number of requests for pollen of various species of pine. Many of these requests have been fulfilled; others which stipulated arrival in time for specific crossing operations could not be fulfilled. The accompanying table is compiled to furnish cooperating pine breeders with the dates and places of pollen collection from various pine species and hybrids. This table will be revised and expanded to cover more species and additional genera as circumstances permit.

On the national forests there has been a trend during recent years toward placing on a systematic basis such fire-control practices as rating fire danger, determining the proper size of suppression crews and speed of attack, and planning fire-suppression strategy. This trend has resulted in greatly improving the techniques of planning and managing the fire-control organization. At the same time it has revealed a serious lack of essential information. The outstanding need is for specific data on the rate at which forest fires may be expected to spread under various conditions of forest...

Tables giving average tree volumes by breast-height diameter classes frequently may be used in timber cruising to save money, time, and men. Such tables may be appropriate in cruises of large areas having many trees in low-intensity cruises warranting the sacrifice in accuracy that results from omission of individual tree height measurements, during wartime when men are scarce or when inexperienced cruisers have difficulty in estimating heights. In response to numerous recent requests from cruisers and forest land agencies, nine of the more important tables used by the Forest Service in...