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Soil nitrogen accumulation beneath a plantation of red alder and Douglas-fir was compared with that under a pure fir segment of the same 30-year-old stand on the Wind River Experimental Forest in southwestern Washington.Beneath the mixed plantation, there were significantly greater amounts of nitrogen in the forest floor and in the upper 24 inches of the mineral soil. Organic matter content in the upper 12 inches of mineral soil was also greater and bulk density at 0 to 3 inches was significantly less. Beneath the alder-fir stand, the carbon-nitrogen ratio was less, both in the forest floor and at 0 to 3 inches.There were 938 pounds more N per acre to a depth of 36 inches under the alder-fir plantation. Consequently, an average of 36 pounds more soil N per acre per year has accumulated beneath the mixed stand than under pure fir.

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Cloud water and rainwater were examined at remote sites in southeastern Alaska and coastal Oregon using standardized collection and analytical techniques. Cloud water and rainwater were characterized by extremely low concentrations of most ions except SO2−4, Na+, and Cl−. Acidity was greater than expected because of organic acids from unknown sources. Concentrations of NO−3 and NH+4 were extremely low, especially compared to samples collected similarly in the eastern USA. Rainwater did not differ between Alaska and Oregon except in concentrations of Ca2+, Mg2+, K+, Na+, and Cl−. Cloud water generally had higher concentrations of ions than rainwater, especially in NO−3, NH+4, and SO2−4. Ion concentrations were highly variable and non‐normally distributed. Sample sizes in future studies should be large (>40). Cloud water deposition may be very important in terms of potential pollution effects and nutrient cycling in ecosystems with frequent cloud cover.

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.