by Carl J. Boxenberger, EMGV
Core aeration is a process by which cores or plugs of soil and thatch are removed from the lawn. Core aeration is done by a machine with hollow tines.
Soils that are prone to heavy traffic are subject to compaction. Core aeration reduces soil compaction by removing plugs of soil which opens up a channel in the lawn and allows water, oxygen and nutrients to penetrate down in the soil.
Core aeration should be done when the grass is actively growing. Fall is the time to core aerate cool season lawns such as tall fescue. Spring and early summer is the time to core aerate warm season grasses such as Bermudagrass.

Core aeration equipment with hollow tines can be rented at local equipment rental companies. There are also professional turf maintenance companies that will aerate your lawn if you do not want to tackle this by yourself.
Run the aeration equipment over your lawn to remove soil cores. Chop up the cores by running a lawn mower over them. If you have a large lawn and a tractor, you can distribute the cores by dragging a piece of chain link fence or mat over them.
Core aerate a few days after a rain. This will have allowed the soil to drain. If you pull plugs when the soil is wet they will form wet clods of soil alongside the aeration holes and actually inhibit air infiltration into the soil, defeating the purpose of aeration.
Further Reading
NC State Extension Turf Files: https://www.turffiles.ncsu.edu/
News alert about zoysiagrass mite damage
https://ncturfbugs.wordpress.ncsu.edu/2019/05/23/zoysiagrass-mite-alert/