Ideally you want to get 8 or 9 plugs removed per square foot to significantly enhance water and air movement into the soil. This may require making several passes over the lawn. Plugs can be removed or left on the lawn. Various other products on the market that claim to control thatch through addition of bacteria or enzymes to the soil have not been proven through research and are not recommended for use. Reducing Soil Compaction Soil compaction occurs in soils high in clay content that receive traffic and sodic soils that have excessive amounts of the sodium ion.
Compaction is enhanced in areas of high to excessive soil moisture that receives traffic.
When this occurs the soil loses structure and forms an impenetrable layer on the surface to water and air movement. It is much like the phenomenon of highway rollers wetting a soil immediately prior to rolling over it to get the highest degree of compaction and stability possible. In a home lawn situation, excessive soil compaction normally occurs near the edges of sidewalks, driveways or where kids or animals normally congregate and play. If soils get compacted and the infiltration of water and air into the soil is impeded, the lawn will certainly begin to decline. Goosegrass and prostrate Knotweed are the best examples of compaction resistant plants.