A greenhouse bioassay was used to compare the effects
of soils collected at different distances from hardwood
species on the growth, mycorrhiza formation, and foliar
nutrient concentrations of Douglas-fir seedlings. Soil
nutrient concentrations and bulk densities were also
determined. Soils were collected from two southwestern
Oregon sites that had been...
Recreational impacts on the subalpine-alpine ecosystems of Mount Rainier National
Park have developed over the past century, and today pose a major problem for park
managers. Field data were collected during the summer of 1987 in the Paradise meadows
area in order to describe visitor impacts on social trails (trails...