Compost, aerobically decomposed remnants of organic materials, is commonly mixed into soil to improve soil fertility and water holding capacity. Grass clippings, leaves, sawdust, kitchen refuse, wood ashes, garden refuse, and shredded newspapers are just some of the common materials that are composted.

Mulch, in contrast, is placed on the soil surface. Mulch affects soil moisture by slowing evaporation, reducing weed transpiration, and reducing runoff. Grass clippings, leaves, sawdust, wood chips, straw, shredded newspapers, and compost are common materials used a mulch. Inorganic mulches, such as plastic sheeting, rocks, and gravel are also widely used.

Commercial water absorbing polymers, such as Soil Moist®, Stockosorb®, and Terra-Sorb®, are water management tools that purportedly reduce evaporation, water runoff, and soil erosion when mixed into soil.


In the Preliminary Activity, you will gain experience using a Soil Moisture Sensor and learn soil moisture measuring technique as you determine the soil moisture of a soil sample.

After completing the Preliminary Activity, you will first use reference sources to find out more about soil and managing soil moisture before you choose and investigate a researchable question dealing with the management of soil moisture.