WHY DO WE AERATE GREENS? (*revised April 17, 2013)
One of the most controversial talked about subjects when it comes to course maintenance and conditioning, is green aeration. Why would any business create a program that results in major loss of revenue and subject themselves to less than favorable daily comments for a period often in excess of two weeks? Let’s face it; no one wants to see this happen. You don’t, we don’t and believe it or not, even golf course superintendents could do without this tedious and stressful process if they could.
The very first fallacy that requires clarification is, greens are aerated (hollow core or removing plugs) twice per season, in our case in mid April, and always the first Monday of October (2013, October 7th). Often, I will receive a comment such as, “Didn’t you guys just do this last month?” or “This the third or fourth time you’ve punched the greens this season” or will ask why XYZ clubs are only aerating their greens once per season. In order to maintain a healthy putting surface over long periods of time it is important to point out that most, if not all golf courses in Canada, are aerating twice per season. Yes, the timing will definitely vary from club to club depending on geographical location and/or climactic conditions, but because we are in the Okanagan region, the reasons we’ve selected these particular time periods are to minimize playing disruptions to club members and mitigate lost revenues to our business. For each aeration recuperation time period of approximately two weeks, lost revenues is upwards of $60,000.00 for all revenue centers or $120,000.00 annually. The result is undisrupted playing conditions for five months straight, May through September, where most golf courses might aerate ideally in mid May and again in mid September. Thus reducing good playing conditions to less than four months in what is already a reasonably short season. In essence, in selecting these time periods, our goal is to appeal to the majority by mitigating disruptions in times of lesser demands by club members.
Now, why do we aerate in the first place? There are multiple benefits to aeration or removing plugs out of the ground. The first priority is to reduce ground compaction, created by daily mowing and foot traffic. The second -which is less known but equally important, is the removal of thatch formation by extracting plugs from the ground we remove upward of 10% of overall material. (We utilize half inch tine unless otherwise required, especially in the fall or after the busy playing season). What is thatch? It is an accumulation of organic material, constituted of living/dying or dead turf, generated over time from fertilizing, mowing, verticuting and the natural life cycle of each plant. In easy terms, thatch accumulates rapidly, forming a layer immediately under the grass surface, preventing water percolation; starving and compromising the plant root system in the process. This results in turf that is highly prone to disease that could cause greens to die. Also important to point out that it is inevitable for Poa Annua to infiltrate and take over green surfaces. With Poa being highly susceptible to thatch accumulation, Poa migration is inevitable and can only be cured by removing the existing turf and resoding with new turf. It is very disruptive with lengthy course closure and costly to replace encountering major lost revenue during that time.
HOLLOW CORE vs. SOLID TINE: Solid tine aeration is done for many of the same reasons as described above, with the exception of thatch removal, which is again made necessary to prevent further compaction and disease threat. Even though holes are punched, they are much smaller in size, 1/8th of an inch versus 1/2 inch and by not removing plugs they will tend to close or heal considerably faster. As with hollow tine, solid tine will be accompanied by a light top dressing or sanding which will act as temporary measures to control thatch formation, true up the putting surfaces by breaking the Poa seed head in germination, while also helping speed up the greens. This type of aeration may be performed 4 to 5 weeks apart in season, depending on temperatures and rate of compaction (you will know this when you try to fix your ball mark and break your tee in the process, then you know it is time to solid tine) and allow water into the ground.
Last, I would like to touch upon the following. In high season April through September, maintenance schedule for major cutting days is Monday, Wednesday, Friday and Saturday with fairways and rough mowing. With tees and approaches cut on Tuesday, Thursday and Sunday, obviously greens being mowed daily. That being said, any other or special projects and procedures such as fertilizing, grooming, solid tine aeration, top dressing, bunker and cart paths edging and the many other special projects required, can only be done on both Tuesday and Thursday, sometimes causing minor disruptions in the process. I was approached last season by many groups playing either Tuesday or Thursday wondering why these particular days were selected to perform these procedures. The real answer is simply a function of timing. When mowing 1 million square feet of fairways every other day and grooming 165 acres overall, leaving very little time to tackle these periodic cultural and required procedures.
At the end of the day, we fully appreciate the inconvenience hollow core aeration may cause to all players by temporally compromising playability, and golf course owners and operators major losses in revenues. But ultimately without these bi-annual procedures we would be putting the long term health of our greens in jeopardy, and making unwise, short term decisions, that would compromise the great conditioning that is expected by ourselves and all club members alike.
In closing, I’m hoping that the above synopsis will provide you with greater insight into these often talked about, yet controversial cultural practices. As always, if you have any questions regarding the above or any other matters, please do not hesitate to contact me at any time of your convenience. Otherwise, we sincerely hope that you are enjoying the current golf course condition. To this point, members and guests alike have been very generous with their comments, hoping this positive energy and trend will continue throughout the summer months and allow each of you to enjoy your membership playing privileges to the fullest for the months to come