Aerification helps remove excess organic matter when a plug is pulled, and helps dilute the existing soil profile when sand is used to fill the hole. Traditional hollow tine aerifiers pull a plug 3-4" in length. This also happens to be the approximate depth of sand and organic matter which has accumulated during the life of the greens. Thus, we are finding that we are reaching the limit of a traditional aerifier being able to break through the built up material, and create a channel to the mix below.
What's the answer to this? We decided to go with the one-two punch again this spring. On Monday, we aerified the greens with 7/16" hollow tines on a very tight spacing. The plugs were removed (organic matter reduction) and the holes filled with sand.
Phase two occurred the next day when we had an outside contractor come to the course with some unique aerifiers, called Dryject. These machines use high pressure water to create a small hole on the surface, and sand is instantly vacuumed into this. The company set the machines to the 4-6" depth we were looking for.
As you can see in the picture, the Dryject was able to get more sand, deeper into the soil profile when compared to a traditional core aerifier.
Between the two processes, we used 90 tons of sand on the greens! Players sometimes ask us why we need to aerfiy the greens when they are in great shape. The answer is that it is this kind of on-going cultural practices which allow us to have great greens throughout the year.
A comparison could be made to a car: Why take it in for maintenance when it's running fine? Because it's that maintenance that keep your vehicle running well. This combination of aerification practices provides the benefits that will help the greens make it through this summer's heat.