Treesearch

Clear-cut units in upper-slope forest types in western Washington and Oregon often have an understory of Pacific silver fir (Abies amabilis) at time of logging. Foresters sometimes hesitate to preserve this advance regeneration, partly because of the possibility that heart rots infecting through logging wounds might considerably reduce the productivity of the resulting stand.

Environmental changes resulting from logging in the Douglas-fir region often create ideal growing conditions for many woody and herbaceous plants. A rapid increase of brush and low vegetation, in turn, can seriously hinder efforts to establish a new stand. Consequently, one argument against partial cutting in Douglas-fir (Pseudotsuga menziesii) is that it opens the forest canopy sufficiently to stimulate growth of ground vegetation and thus makes future stand regeneration more difficult.

Control of bigleaf maple (Acer macrophyllum) has become an important consideration in many western Oregon areas that are managed primarily for Douglas-fir (Pseudotsuga menziesii) and associated conifers. The problem is acute on areas where damaged and defective maples are left after harvest of commercial timber. They sprout vigorously from stump, trunk, and root crown, and interfere with the prompt establishment of a Douglas-fir or mixed conifer stand (fig. 1).

In many parts of the Pacific Northwest, logging operations are moving into rugged terrain as access roads probe deeper into the back country. Because of this trend, it's time to look more carefully at steep slopes and decide on the best possible management practices consistent with maximum protection against erosion.

In timber trespass cases or timber cut studies, a method of estimating d.b.h. is necessary in order to determine the approximate gross tree volume that has been removed.

The summer of 1958 was unusuaIly hot in most of Oregon and Washington, and that of 1959 was unusually dry except in western Washington. Killing of young conifers, similar to that in northern Idaho, was common in a few localities in northwestern Washington by the end of the 1958 growing season, but did not continue in 1959 and was not seen elsewhere. Various other effects of drought were visible during both years throughout the region.

Long-suppressed ponderosa pine seedlings and saplings have a remarkable ability to recover and resume normal growth when released. This fact is strikingly demonstrated by a study begun in 1934 on the Pringle Falls Experimental Forest, near Bend, Oregon.

In certain kinds of forest growth studies, an estimate of diameter outside bark is required for trees as of some previous date. Previously, papers were published by this Station regarding estimation of past diameters of Douglas-fir and ponderosa pine. Since they were issued, new and more complete data have been collected for most of the major species in the ponderosa pine subregion as part of the Forest Survey inventory program.

A study was begun in July 1957 to supplement available data on lumber recovery from old-growth Douglas-fir (Pseudotsuga menziesii) saw logs. This study is part of a continuing program of the Pacific Northwest Forest and Range Experiment Station to develop grade-yield recovery figures for primary products of timber stands in Oregon and Washington.

Fire season severity in 1960 was about average in western Washington but was very high in western Oregon. Severity of the entire season in both States was slightly greater than in 1959. Although spring was less severe, both summer and fall were slightly more severe than comparable parts of the previous fire season. Spring fire danger in western Washington was as low as any in the 17 years of record but was near normal in western Oregon. Summer in Oregon was as severe as any in the past 30 years, while in western Washington the summer was only slightly more severe than normal. The western...