2002-07-08 P & R Packet - Laserfiche WebLink

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Assessing the Soil Texture The first step in the soil sampling process is to use a shovel or spade to dig into the ground. Your hole should be about 6 to 12 inches deep. Next, put a rounded tablespoon of soil in the palm one hand. Spray a little distilled water onto the soil and begin to knead it. Continue until the soil forms a round ball in the palm of your hand. Gently squeeze the soil between your thumb and index finger to form a ribbon that extends over the top of your index finger (Figure 5). Continue to form a ribbon until it breaks. Note how long the ribbon was when it broke and whether it feels gritty or smooth. Compare your findings with the chart below (Table 2). The soil texture refers to the relative amount of mineral part.icles in the soil. Defining the texture will assist you in determining your soils ability to retain water. Soils with some clay content will hold more water than sandy or silty soils. Loamy soils tend to hold the most plant avail~ble water. Soils with poor water retention capacities become obvious during extended dry periods. Figure 5 Table 2 . Ribbon Test No Ball Formed: sand Ball but No Ribbon: loamy sand Feels very Feels very Feels both gritty smooth gritty & smooth 1 inch ribbon sandy loam silty loam loam 1 to 2 i.nch ribbon sandy clay loam silty clay loam clay loam 2 inches or more sandy clay silty clay clay Infiltration Test The coffee can perc test allows you to check water infiltration on your site. . Infiltration rates are best determined when your yard is at or near its water capacity. This usually occurs 12 to 48 hours after the soil has been thoroughly wetted by a soaking rain. To do this infiltration test you will need the following equipment: . a two pound coffee can . a small flat plastic lid . an empty plastic soda bottle (16 once or 20 once size) . a ruler and permanent maker . an extra jug of water Before cutting out the bottom of the coffee can, stick a ruler in the can and measure up from the bottom. Use a permanent maker to identify the inch marks along the inside of the can. Next, pour enough water in the can to reach the first inch marking, then transfer the water to your plastic soda bottle. Make sure to mark the one inch line on your soda bottle. This is to ensure that you always use the same amount of water every time you do a perc test. Cut out the bottom of the can when you have finished marking. At your sampling site, push the can into the soil to a depth of two to three inches, use your guidelines in the can as a reference. If the soil is hard, lay a board across the can and pound it with a hammer. Next, gently firm the soil around the inside edges of the can. By firming the edges, this will redu~ water flow 19