The Miami series consists of moderately well drained soils formed in as much as 18 inches (46 cm) of loess or siltymaterial and in the underlying loamy till on till plains. They are very deep soils that are moderately deep to dense till. Permeability is moderate or moderately slow in the solum and slow or very slow in the underlying dense till. Slope ranges from 0 to 60%. Mean annual precipitation is 40 inches (1000 mm), and mean annual temperature is 52 °F (11 °C).