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During the past four years on most Oregon and Washington national forests average midsummer fuel moisture has shown a general downward trend. Conversely, the lowering fuel moistures have caused a rising trend in midsummer forest inflammability. These trends have been brought to light by an analysis of readings from fuel moisture indicator sticks during the midsummer portions of the past eleven fire seasons (1941-51). The records used are from 65 key fire-danger stations scattered throughout the national forests of the two states.

The Scribner Decimal C is the accepted log rule in the Pacific Northwest. Usually volume, growth and yield tables are expressed by this rule to give them practical meaning. Yet in the research required for such studies, the rule is unsatisfactory because of rounded values and irregular jumps in volume from diameter to diameter and length to length.

Studies by Isaac indicate that regeneration to Douglas-fir following logging often fails because a good seed crop is destroyed in the slash fire. To prevent this loss during a good seed year, early burning before seed fall starts has been recommended. If early burning is too hazardous, only the concentrations of slash should be burned later in the fall. In contrast, during poor seed years, a complete slash burn should be employed to keep the ground open for the next good seed crop. With favorable seedbed conditions and an ample seed supply, Isaac found that good stocking could be obtained...

Young Douglas-fir timber is known to produce much No. 1 Common and Better lumber but, little or no clear lumber. The volume of lumber produced from young-growth timber has become a sizable part of the cut from the Douglas-fir region of Oregon and Washington. No exact figures are available, but it is estimated that more than one-fourth of the lumber produced from this region is cut from young growth. As the volume of old growth decreases, more and more reliance will have to be placed on young growth, so both timber growers and wood industries need more information on the kind of lumber to...

Streams transport their loads by traction (the bed load) in suspension (the suspended load) and as salts in solution (the solution load). The total load is the sum of these three and is commonly called the water quality. The amounts of and variation in stream flow and water quality have become in the past few years accepted criteria for evaluating watershed conditions. Although many of the fundamental relationships between soil, cover and water are known, much remains to be ascertained. Such is the case with suspended sediment loads. That is why the Division of Flood Control Surveys,...

The 1951 forest fire weather in western Oregon is generally conceded to have been unusually severe. In order to compare this season with others, this report uses a scheme for rating fire seasons recently developed by the Fire Research section of the Experiment Station, The rating is based on indices of three weather characteristics which generally control burning conditions. These characteristics and the indices used to measure them are as follows: 1. The severity of burning conditions during dry spells is indicated by the average 4:30 p.m. burning index on the worst 50 percent of the...

Frost observations during the winter and spring of 1949-1950 indicated that pronounced soil freezing conditions existed in the ponderosa pine, lodgepole pine, grass and brush types in eastern Oregon and Washington. Accordingly, a study was designed to determine the occurrence and character of frost under these widespread forest and range types. This paper presents a progress report of observations on soil freezing conditions in these cover types in eastern Oregon during the winter and spring of 1950-1951.

Although the pulp and paper industry of western Washington depends chiefly on logs for its wood supply, the use of pulpwood in cordwood lengths is steadily increasing. More than 75 percent of the 20 plants in the area are equipped to handle at least a part of their consumption in cordwood form. Many plants are remodeling their facilities to utilize additional wood supplies, and without exception greater dependence is placed upon cordwood.

As the supply of old-growth timber in the Douglas-fir region decreases, there will be a continuous increase in the use of second growth. Eventually the entire wood-using industry will be wholly dependent on the younger timber stands, The exact amount of second growth being cut at present is not known, but it is estimated that close to one-third of the lumber production in the Douglas-fir region came from timber less than 160 years old, or what are commonly known as second-growth stands. The acreage of these young timber stands is sizeable. Recent surrey figures show second-growth forests,...

The staggered-setting system of clear-cutting is fast becoming prevailing practice in the Douglas-fir region. The trend is away from large, continuous clear cuts to clear-cutting smaller units of timber of less than 80 acres. These are called staggered settings because the surrounding stand is left uncut to provide seed and serve as a firebreak. Major aims of this system are to obtain better regeneration and reduce fire losses.