Effects of Slash Burning on Some Soils of the Douglas-Fir Region

Abstract

The studies summarized in this paper indicate that effects of slash burning vary with different soils and locations in the Douglas‐fir region and also within an individual clear‐cut and slash‐burned area. Although severe burning damages some soil properties, the soil surface affected by severe burning usually represents only a small portion of the total area logged and burned. As low‐grade materials are utilized more fully, a reduction can be expected in the volume of heavy fuels left after logging. This will decrease even more the small amount of soil surface damaged by severe burning. In weighing the effects of slash burning on soil properties, consideration must first be given to the relative amounts of lightly burned, severely burned, and unburned soil surface. This is necessary to avoid the possibility of assigning to an entire area, the effects of only the most severe burning treatment. It is also emphasized that findings of these studies apply only to intentional slash burns and should not be construed as applying to areas affected by repeated wildfires.

Identification of Activity Areas by Multi-element Characterization of Sediments from Modern and Archaeological House Floors Using Inductively Coupled Plasma-atomic Emission Spectroscopy

“…Cooking provides an obvious example. Wood ash contains high levels of K and Mg, as well as other elements present in the wood tissue that is burned (Tarrant, 1956;Scotter, 1963;Heidenreich et al, 1971) and therefore leaves a very strong, localized signature (Figure 3). Biological residues (with the exception of feces and urine) and detritus brought in on feet and clothing, on the other hand, are shed across much of the occupied area, and will therefore be more generalized in their distribution.…”

“…Wood ash contributes a number of elements to soil (Tarrant, 1956;Scotter, 1963;Jackson, 1967; Heidenreich et al, 1971), particularly K and P, so it seems likely that the concentrations around the centre of the floor ( Figure 6) are due to the location of the hearth. The hearth area had the strongest chemical signature of firing of all the floors examined from the Keatley Creek site, and notably, it was also the only stone lined hearth encountered in the excavation (Alexander, unpubl.…”

Soil properties in fire-consumed log burnout openings in a Missouri oak savanna

“…At AB Savanna significant soil changes persisted for at least 3 years following consumption of downed logs (Tables 1 and 2). Combustion of logging debris increased soil pH by 2.8 units in northwestern North American conifer forests (Tarrant, 1956) and by 3.6 units in southeastern Australia (Bauhus et al, 1993). Following low intensity slash fires, soil pH returned to within 0.5 units of original conditions within 2 years of combustion (Tarrant, 1956).…”

“…resulting from severe fire behavior. Heavy fuels such as CWD, logging residue (Tarrant, 1956) or deep organic matter layers (Sackett and Haase, 1992) increase fire intensity, the depth of temperature penetration into the soil and the duration of soil heating effects (DeBano et al, 1998;Giardina et al, 2000). For example, beneath a Eucalyptus log pile, soil temperature exceeded 300 8C at 5 cm depth 7 h after the fire was ignited (Roberts, 1965); for more than 24 h following ignition, soil temperature surpassed 100 8C to a depth of 22 cm.…”

Pile burning creates a fifty-year legacy of openings in regenerating lodgepole pine forests in Colorado

“…The influence of slash pile burning on soil temperature (Roberts, 1965) and soil chemical and physical properties (Tarrant, 1956a;Dyrness and Youngberg, 1957) have been researched for more than 50 years. The quantity, arrangement and moisture content of fuels within burn piles are intended to promote complete combustion and as a result, the short-term effects of pile burning are more severe in concentrated areas than those of either wildfire or broadcast burning (Ahlgren and Ahlgren, 1960;Wells et al, 1979;DeBano et al, 1998;Wan et al, 2001).…”