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Show Drive the sharpened boards into each of the two spots to a depth of 6 inches. Leave them there and observe them after the first rain. Or fill a sprinkling can and, holding it the same height ( 3 to 5 feet) above the two spots of ground, sprinkle an equal amount of water an equal distance from each stake ( about 1 foot). After the rain, or after using the sprinklers, note the difference in the amount of soil splashed and the height it is splashed on each board. Another way to note the removal of soil by splash erosion is to place some coins or flat stones on bare soil and use a sprinkler as before. Observe what the falling water does to the soil around the coins. You can show this indoors if you place a jar lid full of soil in the center of a white sheet of paper or cardboard about 3 feet square and hold a sprinkler over it. You can show the value of soil cover in preventing splash erosion by placing perforated fruit- jar lids, topside down, over two pint fruit jars. Fill each lid with the same kind of soil, level full. Place grass clippings on one and leave the other one bare. Set the lids side by side and hold a sprinkler over both, letting the water fall about 3 feet. Observe what happens to the water. The bare soil will be splashed out of the lid. More water will soak through the sample with the grass clippings. INTERPRETATION You can observe the effects of splash erosion after any hard rain. Small pebbles will be perched on pedestals just as the coins were. You can also see splashed soil in gardens and schoolyards, on sidewalks, on vegetables and flowers, on basement windows and picket fences. One of the reasons for mulching strawberries is to keep splash off the fruit. Soil particles must be dislodged before they can be moved. This is one part of the erosion process. When raindrops fall on bare soil, much energy is expended. Small clods and soil granules are broken down by the impact of the falling drops of water. Studies made by the Soil Conservation Service show that from 1 to 100 tons of soil per acre may be splashed into the air during one rain. This splashed- up soil consists of single particles that have been dislodged from the soil mass. Thus, they are easily transported from their original location by any water movement on the surface, no matter how slight. There need not be a steep slope for this kind of erosion since fine particles can be carried by slow- moving water. You will find that soil particles are splashed to NY- 20.339- A Small pieces of stone are left on pedestals of soil after beating rain has carried away the soil around them. 17 |