This past week we aerated two of our practice greens to determine what method is going to be used on the course this year (August 6th for those that are interested). The objectives that I am hoping to achieve are to reduce thatch and break up a pan layer that has developed. A pan layer is a hard layer that shows up just below the depth of which we typically core aerate. Not uncommon, but somewhat surprising considering we do utilize a deep tine aerator.
The first method done on the BBQ putting green was 3/8" hollow coring tines on 1.5"x1.5" spacing. This removes a lot of thatch and the holes are then back-filled with sand increasing drainage. This doesn't address the pan layer, but that could possibly be addressed by additional deep tine aerations throughout the season which is not disruptive to play.
The second method tried was on the East Putter where we applied 3/8" of sand first and then used the deep tine aerator to punch 3/8" holes with a solid tine on 1.75"x2.0" spacing by a depth of 8 inches. This gives us big drainage channels that get through the pan layer and by applying the sand first, we aren't left with any tire ruts that the sand topdresser typically leaves behind. While this method doesn't physically remove any thatch, we are diluting it.
Next week we will try another method where we do the 3/8" deep tine followed by a 1/4" hollow tine core and then followed by sand. An all-in-one cultivation event! The reason for all of the different methods is so I get what I want from aeration and I provide the least impact to you, the customer.
If you are a superintendent reading this, please chime in with your thoughts on core vs. no core. It is an interesting subject. I can be reached at firstname.lastname@example.org or hit me on twitter; @bboyer925.