Timber Harvesting Residue Treatment: Part 1. Response of Conifer Seedlings, Soils and Microclimate

• Published in: Forest ecology and management Vol. 126; no. 1; p. 25
• Main Authors: Zabowski, D, Java, B, Scherer, G, Everett, R L, Ottmar, R
• Format: Journal Article
• Language: English
• Published: 01.02.2000
• ISSN: 0378-1127

At four study sites located on the eastern slopes of the Cascade Mountains, WA, harvesting-residue treatments were evaluated in terms of the response of conifer seedlings, soil capacities, and microclimate. The treatments involved varying the intensity of burning, varying the timing of burning, chopping, and removing unmerchantable materials. The residue treatments were installed in the spring and fall of 1989, and Douglas-fir and lodgepole pine were planted the following spring. Results showed that Douglas-fir growth was enhanced with either low-intensity spring burning or no slash treatment, while lodgepole pine growth favored either burning or clearing of residue. Soil bulk density did not appear to regulate seedling growth rates, but soil temperature was important, and burning or removal of slash exposed the mineral soil to increased solar radiation earlier and later in the growing season. Residue treatment effects on maximum air temperatures were not evident at the higher-elevation sites, but burning elevated minimum air temperatures.