Healthy soil is composed of sand, clay, and silt.
These three ingredients are found in various proportions in all soil. Loamy soil can be found near the rivers in Eugene, but most of the soils in the other parts of the city have a high clay content. Healthy soil is permeable soil so that it doesn't retain too much water. Permeability refers to the rate at which water drains through the soil. Soil with heavy amounts of clay can be made more permeable by adding organic matter such as compost.