Treesearch

Intensity of a slash burn is often judged by the change in soil color. Reddened or yellowed areas of soil and charred patches of organic litter are found on most burned areas, but such color changes are difficult to interpret. A study was therefore made to explore two questions: (1) At what temperature does the color of mineral soil change to the reddish or yellowish hues found on severely burned spots? (2) How do high temperatures of varying duration affect soil reaction (pH)?

How did the potential burning conditions of the 1952 fire season compare with those of previous years? The answer is important to those who protect forests from fire. Knowing the relative severity of the burning conditions will help them judge the effectiveness of their fire protection programs. This paper reports ratings of the weather factors most closely related to burning conditions, that is, to the start and spread of fires. The ratings show that in comparison with previous years, the 1952 fire season weather was of near normal severity for the season as a whole, but was much above...

Young ponderosa pine produces a good grade of common lumber, and close-grown trees produce better grades than those which were open-grown. This was shown by a study at the Pringle Falls Experimental Forest near Lapine in central Oregon.

Rodent control is one of the most critical problems in reforestation by direct seeding. Several different types of rodenticides, baits, and repellents have been developed, but none have been completely satisfactory.

Proper thinning of dense young stands of ponderosa pine increases the growth rate of remaining trees and thereby shortens the time required to grow timber of any desired size. The extent of improvement in growth is shown by thinning studies in the Pacific Northwest covering periods of 10 to 24 years. These studies, together with general experience and research in other pine regions, are summarized in this paper. The discussion is largely confined to stands of premerchantable size, which now means stands not yet producing saw logs at least 8 inches in diameter.

Despite a number of published studies and observations of the factors affecting the distribution of lodgepole pine (Pinus contorta var, latifolia) and Ponderosa pine (Pinus ponderosa), some misunderstanding still exists as to the significance of the extensive stands of lodgepole pine in the ponderosa pine zone of Oregon and Washington. At times there even have been proposals to destroy the lodgepole "weed" stands and replant the areas to economically superior ponderosa pine. These proposals were based on the assumption that lodgepole stands are the direct result of fire and represent...

Does planting stock that has been kept in storage survive and grow as well as freshly dug stock? This question is important because the ground at a forest nursery may still be frozen when spring planting time arrives in the warmer parts of the region. This means that seedlings for spring planting need to be dug in the fall, kept in cold storage over winter, and shipped to planting sites in the spring. If this procedure is not satisfactory, it will be necessary to ship seedlings in the fall and heel them in at the planting site, or build new nurseries in the warmer areas.

Sawmill companies often must decide whether it is more economical to sort and sell peeler logs than to cut them into lumber. If the mill owners have reliable data on the grade of lumber that can be expected from these logs, they will be better prepared to make the decision. The Pacific Northwest Forest and Range Experiment Station has made several lumber grade recovery studies at mills located in the Eugene area, Coos Bay area, and in southern Oregon. No single study has sufficient logs fin the peeler grade to give adequate sampling. Therefore, the data on Douglas-fir peeler logs from four...

In the Pacific Northwest logs are often scaled in lengths which average about 32 feet to facilitate logging. Although several excellent Western hemlock, Sitka spruce and Douglas-fir volume tables based on a 32-foot scaling length have been available for some time, they provide for a larger top diameter than is now used in actual practice. Other tables specify a satisfactory top diameter but are based on a 16-foot scaling length.

The service life of lodgepole pine fence posts can be greatly extended by a good preservative treatment, After more than 15 years, however, little or no difference can be found between treated lodgepole pine posts and untreated Western redcedar posts. These conclusions have been reached as a result of observations on 517 lodgepole pins posts for 16 years and 355 cedar posts for 19 years on the Pringle Falls Experimental Forest in central Oregon.