Treesearch

As young-growth forests replace old-growth forests as the primary source of Douglas-fir raw material, the technique of managing young stands becomes increasingly important. Managers of young-growth timber need to know whether it is economical and silviculturally feasible to make thinnings in stands that are close to rotation age. Final harvest of some stands of this age might be delayed for perhaps two decades if in the meantime some income could be obtained from them in the form of thinnings.

The manufacture of lumber from logs is always accompanied by the accumulation of wood fiber in the form of sawdust, slabs, edgings, trim, and shavings which is of little commercial value. Sawmills use a portion of this "residual" wood fiber for generating steam with which to run the mill and dry kilns, some is used as a raw material for other industries, but much of it is still disposed of in burners.

Late in the summer of 1951 the Port Angeles and Western Railroad fire (commonly called the Forks fire) killed more than a half billion board feet of timber. An area approximately 20 miles long and 2-1/2 miles wide, covering 32,668 acres, was burned. It included fine virgin timber, thrifty plantations, ranch lands, reproduction areas, advanced young growth, logged-off land, and slashings.

Wind damage is serious in the forests of the Oregon Coast Range. For example, on December 4, 1951, one severe storm blew down 3.7 billion board feet of merchantable timber.

The inflammability of Oregon and Washington national forests during the middle of the 1952 fire season was slightly lass than the 12-year record high set in 1951 (table 1). The rating is based on the 25 lowest daily observations of fuel-moisture indicator sticks in the July 16 to August 21 period. Stick readings from 64 key fire-danger stations near the exterior boundaries of the national forests were used in this study. This is the fourth annual report on midsummer fuel moisture.

Following two successive fire seasons of record breaking severity, the 1953 season set new records for low fire danger in western Oregon and Washington. The low danger is reflected in the fire record—the U. S. Forest Service and forestry offices of both States all report the lowest acreage burned since fire records have been kept. A cool, wet spring, above normal relative humidities during the summer, general rains in late August, and recurring fall rains were largely responsible. October weather was the most favorable for burning logging slash of any fall period in recent years.

Careful selection of trees to be pruned can make the difference between profit and loss on the pruning investment, especially in stands where no thinning is contemplated. Expert marking is required to make sure that the pruned trees will grow rapidly. The most important variable influencing the cost of clear wood produced by pruning is growth rate. For example, at 3 percent interest, the cost of producing clear wood at harvest is $20 per M b. m. for trees growing 2 inches per decade, while the cost is only $12 M b. m. when the growth rate is 3 inches per decade.

One question frequently asked by foresters in the Douglas-fir region is: "How much land is taken out of forest production by logging roads and landings?" The final answer is not known, but a rough estimate recently prepared for a sizable portion of the H. J. Andrews Experimental Forest may be useful as a tentative figure. The experimental area is located about 50 miles east of Eugene, Oregon on the Willamette National Forest and is fairly typical of the old-growth Doughs-fir forests that are found on steep watersheds in the Oregon Cascades.

Dwarfmistletoe (Arceuthobium campylopodum forma typicum (Engelm.) Gill) is widespread in the ponderosa pine forests of Oregon and Washington. The importance of dwarfmistletoe as a damaging agent in the pine forest of the Pacific Northwest was described by Weir in 1916. In some localities present infestations are so heavy that forest productivity is doubtless greatly lowered. Many observers consider that even moderate infections cause growth reductions that are unwarranted in managed forests.

Quick and adequate regeneration of Douglas-fir forests as they are harvested is a major forest management problem in the Puget Sound region. Clear-cutting by staggered settings has not always resulted in adequate regeneration even where no part of the area is more than one-fourth mile from a seed source. Single tree selection, experimented with extensively, has many times been followed by excessive windthrow, injury, decay, and shock to residual trees. Furthermore, tree selection has favored regeneration of the more tolerant species of the stand over the more valuable Douglas-fir. However,...