Serving Western Canada from BC to Manitoba
Salmon Arm Golf Club Aeration / Renovation Program
The Case for the Drill&Fill and Deep Drill
#16 Green 2010 – Poa to sod conversion - March 23, - Bentgrass A-4 sod was placed on the existing USGA – Istric approved rootzone. Seeded originally in 1994 with Providence bentgrass and evolved to 100% poa including poa reptans by 1998.
The sod took excellently and the green was opened to play April 21, 1 month later. But all was not well, by early June it was apparent that the Bentgrass was not performing well. Even minimal applications of water caused puddles – sometimes as little as three minutes, a turn of the sprinkler heads. Trying to dry out the green would result in salts being wicked up through capillary action causing brown foot printing around the flag position.
Original thoughts about the cause were the sod to rootzone layer interface. So a comprehensive aeration program was implemented for the remainder of the year – 5 aeration procedures were performed ranging in size from ¼” – ½”.
By June 2011, the following year, it was obvious the problem lie deeper in the rootzone. The cause proved to be blockage of silt and fines in the choker interface layer between the rootzone and the drainage field about 12-14” below the surface of the green. The poa could grow in this poor draining rootzone, but the bentgrass could not tolerate it.
The question now was “What to do about a green we just spent close to $8000 to resurface? A rebuild of the rootzone and gravel interface would be a project in the magnitude of $20,000 or more. When you factor in the length of time the green would be closed due to a rebuild with potential loss of revenue and the negative public relations backlash, a less invasive and costly solution was really needed.
To add to our challenges at SAGC, we already had 9 other problem greens. During construction of these nine greens in early 1980, very coarse angular sand was used for the rootzone. This rootzone included particle sizes well above 5 mm. This sand proved to be unsuitable for topdressing in subsequent years. The more suitable sand developed into a layer over top of the more coarse sand. Layers in the rootzone produce a water holding barrier, the layer above must saturate before the layer below will drain. This leads to root decline due to anerobisis, and the toxic H2S gas that is produced.
My theory about layers and roots is that roots will not grow much past the middle of the layer it is growing in. Educators & scientists – please feel free to prove or disprove this. Over ten years of aggressive aeration including deep tine aeration provided me with a nick name “punchy”, but really only an effective rootzone of 6” -7”. According to my theory the maximum root in that 6” rootzone will only be three inches, we were lucky to have half of that. When I first arrived in the summer of 1998 on #4 green, I changed the hole and the root plug was barely ¼” thick. It looked like a thin hockey puck.
Our challenge - 10 of our greens had layered rootzone problems that really were asking to be rebuilt.
We decided to remove and replace the rootzone with a machine that had been around for over 25 years. - The Drill&Fill and the Deep Drill. The machine drills out the rootzone and replaces it with USGA sand or your desired rootzone amendment to depths of 12”. And because the holes fill from the bottom up and completely, there is no settling afterwards. This results in a green surface that is immediately playable after the procedure. In the Deep Drill mode the machine is capable of drilling to depths of 16”. The golfers aren’t put off by how the green putts after a procedure so discounting rounds isn’t usually necessary.
In the fall of 2011, the club decided to purchase a Drill&Fill Machine, reasoning if the machine solved the problem with #16 and the other problem greens it would pay for itself.
In the spring of 2012, on #16 green we performed 2 - 16” Deep Drill procedures to drill through the choker layer into the gravel. We followed those procedures with a 12” Drill&Fill procedure to form new channels of sand to feed the drainage holes we provided deeper in the green with the Deep Drill. We have since performed another Drill&Fill on #16 in the spring of 2013. So far the results have really been remarkable. The green is still about 80% bentgrass and we can keep the moisture level in the rootzone where we want.
We have been able to reduce our invasive aerification program from 5-6 procedures per year down to 2 minimally invasive ¼” aerations which we perform in the off peak season months. Thatch development wasn’t a problem for us on greens, we never aerated because we needed to remove thatch. It was always to open the greens up to let them breathe because they wouldn’t drain properly.
Since 2012 the greens and the number of times we have used the Drill&Fill are #16 – 4 procedures, #4 – 3 procedures, #5	 – 2 procedures, #1, #3, #8, #11, #15, #17 & putting green – 1 procedure. All the others are non-layered greens and have no rootzone problems; we haven’t used the machine on them. In 2014 we have only used the Drill&Fill on #4 green.
#16 Green Aeration / Renovation Procedures
2010
Mar 23, Sod A-4 on existing 80/20 rootzone
April 21 Opened for play
By early June it was apparent the green was not draining properly, initial thoughts were the sod to sand interface. So an aeration program to remove the interface was initiated. Later, a plugged choker layer proved to be the cause.
June 30 Aerate ¼” solid 2”x2” spacing
July 14 Aerate ¼” side eject 2”x2” spacing - 1 hopper sand
Aug 20 Dimple seed weak areas 007
Sept 1 Verticut x2
Sept 8 Aerate ½” hollow 2”x2” - 2.75 hoppers sand (heavy)
Sept 27 Aerate ¼” hollow 2”x2” spacing - axis topdressing
Oct 8 Aerate ½” hollow 2”x2” spacing - 2 hoppers sand & 14 bags axis
2011
May 18 Aerate ¼” hollow - no topdressing
June 8 Aerate right side ½” hollow - axis topdressing
June 13 Aerate ½” 6”x6” spacing solid Deep Tine Wiedenmann - sand & 60 bags axis
Sept 7 Planetaire
Sept 12 Aerate 3/8” 6”x6” spacing solid Deep Tine Wiedenmann
Oct 4 Aerate ½” 2”x2” spacing
2012
April 17 Deep Drill 5/8” x 16” – no topdressing
May 2 Deep Drill 5/8” x 16” – no topdressing
May 7 Drill&Fill ¾” x 12” filled w 1mm sand
May 3 Aerate 5/8” hollow 2”x2” spacing – no topdressing
Aug 22 Aerate ½” hollow 2”x2” spacing w topdressing
Sept 10 Aerate ½” hollow 2”x2” spacing w topdressing
2013
April 9 Drill&Fill ¾” x 12” filled w 1mm sand with aeration 5/8” hollow 2”x2” spacing
July 12 Hydroject
2014
April 24 Aeration ¼”hollow 2”x2” spacing – no topdressing
Sept 2 Aeration ¼” hollow 2”x2.5” - light topdressing
