Percent Organic Matter Test:

For this test, our soil sat overnight in an oven to evaporate all of the moisture out of it. It was then placed in a crucible and weighed 83.5 grams. The crucible then sat above a bunsen burner in order to burn off all of the organic matter. It is lost due to the conversion of organic matter to carbon dioxide and water at high temperatures. After about 30 minutes of being heated, the bunsen burner was turned off and the crucible left to cool. Five minutes after it was cooled, we went to weigh the new mass. However, we spilled the soil and human error is not accounted for in our calculation of organic matter in the soil. The end mass, 73.1 grams give or take a few then lets us calculate the percentage to the best of our ability.

(83.5 grams - 73.1 grams)/ 83.5 grams = ~12.5% organic matter

 It is not necessary to measure the mass of the soil alone because the mass of the crucible never changes. It is the same in the beginning as in the end and you are not testing the mass of the soil, but the change in mass from beginning to end. It is important to have organic materials in the soil because having organic materials improves the infiltration of water and air by increasing pore space. In addition to it helping with the pore space of the soil structure, it also loosens soil making it easier for plants to spread their roots. A second reason why organic matter is important is because it increases water capacity. It is said to be that organic matter is 1,000X more absorbent than just plain minerals. A third and final reason why organic matter is important is because it adds nutrients to the soil. Without natural nutrients, most plants would not be able to grow without man-made fertilizers. These nutrients are released into the soil as organisms in the soil digest and decompose their "food" or organic matter.