Greens Aeration Completed, A Detailed View

Our spring deep-tined greens aeration was completed on Tuesday afternoon.  I've attached a few video clips of the work and will discuss in greater detail why we must do this work.

Almost all modern courses are built with a 12" sand base with a 4" pea gravel and pipe drainage system which helps to drain excess water from the profile.  Below is an example of this construction.  #9 green is built with this construction except the thin tan area(choker layer between the gray(gravel) and brown(sand) is left out.  The rest of our greens have just 4" of sand and then soil from their original construction 100 years ago at its base.  There is probably a cinder layer and some clay tile that were placed in old style greens but they are all but useless to us now.

USGA Spec Green Profile

The above green construction is designed to create a perched water table.  To perch means in this process that the water rests, stays above the drainage providing moisture for the root systems as it slowly moves through the system.   The movement of water through the sand profile occurs through capillary attraction.  The sand particles are similar in size and air spacing and the water penetrates more freely through this zone.  Once it reaches the gravel layer, the sand layer must reach a certain saturation point before it will release into the gravel layer.  In a golf green this is important.  We want the water to pass through the system but we also want it to move slow enough so that the root system can absorb the some of the moisture and sustain life.  Life is good!  We only have one green with this construction.  #9

We aerate for a number of reasons:

1. Water penetration.  We want the water to move from the green surfaces into the root zone.  Dryer surfaces usually means improved play-ability and turf health.  Smaller ball marks and reduced wear and tear from foot traffic which can effect ball roll.
2. Gas exchange.  Oxygen enters the root zone and excess carbon dioxide which is harmful to roots and microbes exits.
3. Improves rooting.  The long channels of sand that go down into the soil layer of our greens improves rooting depth, overall health, and drains water through the profile.
4. Topdressing of the greens helps to smooth the surface and reduces thatch.

Below are a three videos from our work on Monday-Tuesday.  I included the actually aeration of Green #11, blowing sand in the holes of #13, and brushing the greens with #10. I did not have video of the topdressing of the greens and rolling of the greens after the process to smooth them out.  I would expect the greens to be in good shape by Masters weekend.