Oxygen availability to the roots of the grass plants on a golf green is an essential component for a healthy green. With golfers and mowers walking and rolling over the green's surface each day the surface can become compacted and limits oxygen exchange into the rootzone.
Here Luis is using an aerifyer, equipped with 5mm diameter tines to punch holes in the green. These holes provide channels for oxygen to permeate the turfgrass rootzone and allow the roots to "breath." The holes also offer improved infiltration of water (rainfall) to move into the subsurface rather than water puddling on the surface.
Once we roll over the greens one time and mow them, the holes are not even visible and the ball roll is not affected. We will do this process to the greens every week or two in the summer months. This process is called "venting" or "needle tining" the greens.