Create pockets for air, water, and nutrients
Foot traffic compacts the soil underneath turf and restricts the flow of water and nutrients to turf roots. The best way to open up compacted soil is to create entry points for air, water, and fertilizer with a core aerator. Similar in size to a lawn mower, a core aerator has a series of tines mounted onto a rotating drum. Since this machine costs between $5,000 and $10,000 to buy, I rent one instead for $50 a day.
There are two types of aerating tines, and turf professionals are still debating which works best. Current opinion is that hollow tines, which remove plugs of turf, roots, and soil, are best used to aerate compacted clay soils. Solid, spikelike tines that poke holes in the turf but don't remove plugs are best used to aerate sandy soils.
Use an aerator to relieve compaction.
An aerator removes plugs of turf so air, moisture, and nutrients can get to roots.