Nutrient Release from Mount St. Helens Volcanic Ash and Retention by Western Montana Soil

摘要

Three western Montana soils of varying fertility and physical characteristics were placed in large tubes, covered by different depths of volcanic ash from Mount St. Helens eruption to test the release of ions from ash and ion storage or loss from the soil. The ion concentration differences between water added and water lost from the soil were used to show net ion storage or loss from the soil. Lettuce and conifer seedlings were grown in the leached soils to estimate the influence of ash on growth. The three soils responded to ion additions differently. Ash improved lettuce growth for only the calcareous soil. Of the four conifers tested, only ponderosa pine seedlings on the poorest soil showed improved growth with ash the first year.