Deep tines that are 1/2 inch in diameter are used to created long channels for healthy root growth.
Quad tine using 1/2 inch holes are used the aerate the greens to remove thatch and create space for healthy bentgrass
Holes are back filled with sand to aid I. Drainage and oxygen for the root system
Here the you can see the open holes are from the deep tine machine which is completed after the core aeration has been accomplished.
With good weather all holes are healed over with in 21 days