Imagine a heavy rainstorm, typical in the wet tropics, falling on an intact hillside forest. The forest’s many levels of leaves and branches act like stacked umbrellas, softening the impact of the intense rain. Trees, shrubs, vines, mosses, and litter shield the soil from the direct impact of the rainfall, while roots act like underground nets holding the soil in place. After the storm has ended, roots and animal burrows transport the fallen water into the earth. At the same time trees pump water back into the sky as clouds, cooling the air and sending moisture downwind. Water also runs off overland feeding streams and rivers.