Treesearch

Arizona sawmills turned out 329,859,000 board feet of lumber in 1960. New Mexico's lumber production in the same year was 227,773,000 board feet. Output in both States was generally in line with the upward trend in production in recent years.

The first complete inventory of Wyoming's forests indicates a present timber volume of 22.6 billion board feet on the 4.9 million acres of commercial forest. Sawtimber stands occupy three-fifths of the commercial forest area and are largely overmature. Timber products output was 7 percent greater in 1962 than in 1957 and there are opportunities for greatly increasing the cut. Other forest values-water, recreation, and grazing-provide very important benefits to the State and the Nation.

Seventeen years of cattle grazing on ponderosa pine-bunchgrass ranges show that a moderate grazing rate of 30-40 percent use of the dominant grasses and sedges was best for sustained forage and livestock production. Plant vigor of the principal bunchgrasses, Festuca arizonica and Muhlengergia montana was somewhat comparable on lightly (10-20 percent use) and moderately grazed ranges but decreased appreciably on heavily grazed ranges (over 50 percent use). Perennial grass and sedge production under moderate, light, and heavy grazing was 335, 446 and 148 pounds of air-day herbage per acre,...

Growth of the shoot apices of 91 trees in a 45-year-old Pinus ponderosa Laws. provenance test was measured periodically with a transit. Analysis of the measurements led to the following conclusions: (1) 19 races of ponderosa pine planted near Priest River, Idaho, showed phenological, morphological, or physiological variation in six characters: date of beginning growth in the spring, date of ending growth, total seasonal elongation, duration of growth, length of dormant terminal bud, and rapidity of growth; (2) the variation described is continuous, although it was not possible to associate...

The instrument developed by Intermountain Forest and Range Experiment Station to record duration and amount of dew (fig. 1) consists of an expanded polystyrene block mounted on a balance, a clock-driven drum, and a pen geared from the balance to the drum. Changes in weight of the expanded polystyrene block as dew or rain is deposited are recorded on a chart mounted on the drum. This record shows the amount and time of dew formation and dissipation. The instrument also records time and amount of rainfall.

The objectie of the study is to obtain information on the growth and yield of even-aged stands of different stocking levels. The plot will also serve as the start of a detailed growing stock study for the ponderosa pine region.

History is replete with stories recounting the failures of man to recognize, control, and conquer the devastating effects of sediments from steep mountainous lands. Learned men have documented the reasons for the tragic downfall of highly developed civilizations in Mesopotamia, Israel, Egypt, and elsewhere. Most agree that it was not conquest of the land by an invader, nor the loss of fertile fields which depopulated the land, but that the relentless encroachment of silt into the canals and rivers forced the people to move elsewhere or starve.

The most destructive decay of aspen (Populus tremuloides Michx.) is caused by Fomes igniarius var. populinus (Neu.) Camb. This fungus accounted for 59 percent of the decay found in a recent study of aspen in Colorado. It is almost impossible to find stands of any age that are not damaged to some degree by F. igniarius, and trees with advanced stages of decay usually bear numerous sporophores or conks.

The growth and performance of Pinus monticola, P. strobus, and their hybrids were investigated at several sites in northern Idaho and western Montana. At three sites in northern Idaho, two hybrid progenies were approximately twice as tall and markedly excelled corresponding P. monticola progenies (having the same female parents) in height growth at age 8 years . At one site in western Montana none of the few P. monticola, P. strobus, and hybrid progenies performed satisfactorily. All except a high-elevation P. monticola source from California were severely damaged by snow.

This paper reports the final phase of research that has determined the flammability of slash for nine species of northern Rocky Mountain conifers at three ages. Visual characteristics, rate of fire spread, and fire intensity for 5-year-old slash were studied by essentially the same methods as had been used previously on freshly cut and 1-year-old material. Final experimental burning was done in July and August 1960 on a specially prepared site in the Priest River Experimental Forest in northern Idaho.