Compaction can adversely affect nearly all physical, chemical and biological properties and functions of soil; it is regarded as the one of the costliest problems caused by conventional agriculture. Pressure caused from the use of heavy machinery and inappropriate soil management can lead to the compaction of subsoil, creating impermeable layers which causes the soil to restrict water and nutrient cycles. This can cause abnormal root growth and can lead to reduced crop growth, yield and quality as well as increased surface water run-off and soil erosion.

Push the soil compaction tester into the soil, record the depth at which the 300lbs level is exceeded, using the gradients on the penetrometer rod. This level is the top of the compacted zone. Continue pressing the compaction tester down. Record the depth at which the penetration falls below 300lbs. This is the bottom of the compacted zone.