Soil Sampling and Storing

• When collecting soil samples, it is recommended that several samples be taken for accurate test results. A common practice is to mix the soil samples to obtain the "average" of the samples. Be sure to use a clean tool with no residue or rust. Spring or fall are the best times to take soil samples.
  
  Soil should be analyzed within 24 hours of collection because its contents can be altered over time. If you cannot test within 24 hours, you should freeze the sample. If the soil is properly dried in an oven or with an evaporation container, it can be stored up to six months.
  
  

What to Test For

• Soil tests can be used to test for major soil nutrients like phosphorus, nitrogen and potassium; secondary nutrients like sulfur, calcium and magnesium; and minor nutrients like iron, copper, boron and zinc. Soil may be tested for physical properties such as acidity and electric conductivity. Other soil tests performed measure organic matter, moisture content and soil contaminants. Soil contaminants include benzene, toluene, xylene and petroleum.
  
  

Tests for Soil Nutrients & Contaminants

• Simple soil testing kits that test soil for specific nutrients and pH level can be purchased at your local garden center. However, if you would like more detailed soil testing to reveal contents and contaminants in the soil, you may want to send the soil samples to a lab. If you choose to send soil samples to a lab, choose a local lab with a good reputation and references to ensure quality of work.
  
  

Hand Soil Test

• Testing your soil by hand is a simple process and involves no special skills or equipment. Pick up a handful of soil and feel it. Rub it between your fingers. If the soil feels rough and grainy, it is sand. If the soil is sticky, it is clay. If the soil feels slippery with small gravel pieces, it is silt.
  Form a clump with the soil sample, then try to crumble it. The ability of the sample to crumble will determine its type.
  
  

Jar Soil Test

• The jar test takes three to four days to complete. You will need a liter jar or larger. Add two inches of soil to the jar and fill 2/3 of the way with water. Mix in 1 tsp. of liquid dish soap seal. Shake the mixture. Wait for one minute and allow the soil to settle. First, measure the bottom layer. This is the sand layer. After waiting for two hours, you may measure the middle layer, the silt. To measure the clay layer, you must let the jar sit for several days, then measure. Whichever layer is the largest is the majority of your soil type.
  
  

Other Tests

• The soil percolation test and the soil profiles test are required to be performed before building or installing a sewage system. The percolation test is used to measure the ability of soil to absorb liquids. It is performed by drilling three test holes and soaked with water. After the holes have soaked, they are filled 10 inches with water. Then the rate of percolation is recorded. In the soil profiles test, the same three test holes are dug, but they are used to analyze the soils texture, presence or absence of water, and depth until rock layer beneath.
  
  A new type of soil testing, cone penetration, can be used for various soil testing applications including off-shore (for drilling purposes). Cone penetration uses push technology to create friction in the cylinder-shaped penetrometer. The friction is measured and recorded electronically.