More aggressive core aeration is necessary if we are to ever have the consistent firm and fast surfaces we all desire
When I arrived at Granite Bay just prior to the 2008 golf season there were two items that were high on the Memberships concern list. First was the deteriorated condition of the sand traps and their need of renovation, and second was putting surface roll & speed. In 2008 we embarked on an “in house” bunker renovation project and have just recently completed all green side bunkers. This work has been well chronicled.
Additionally in 2008 we addressed the green speed issue by introducing regular greens rolling and manipulating, or better said lowering our mower heights of cut (HOC) to achieve a smoother and faster ball roll on the putting surfaces. We were successful in getting ball speeds on the greens from 8 to 9 feet on the stimpmeter to 10 to 11 feet. We targeted a goal of 10.5 to 11 feet as a fun speed for the membership as a whole hopefully leaving room to tweak them up to 11.5 to 12 for special events. Admittedly we were only moderately successful in achieving a consistent 10.5 to 11 feet. The reason for this moderate rate of success and quite frankly for the softness of the greens and entire golf course for that matter is an accumulated organic layer called thatch
. Once this thatch layer becomes too dense it acts as a sponge and fills with water then the layer becomes black or anaerobic because of the total lack of air.
This produces an “ inhospitable place for plant roots to grow. The pore space in a dense organic layer is dominated by small water-filled capillary pores, while the large air-filled macropores are lacking. Oxygen is necessary for the plant to carry out respiration, which is the conversion of stored food to energy. Respiration takes place in the roots and, therefore, good air exchange in the upper soil profile is vital to plant survival.” (USGA Green Section Record- Core Aeration By The Numbers by Chris Hartwiger & Patrick O’Brien)
Lowering our mowers, double cutting and rolling the greens sometimes as much as five times a week are common practices to produce a faster, smoother ball roll. And if our greens were healthier and were not excessively thatchy, they should be able to handle these procedures. However their current condition is very sensitive as evidenced by turf loss on some of our greens. Everyone likes a smooth fast ball roll on the greens, but if we don’t have healthy condition below the surface, and still try to produce speeds with above the mentioned common practices, you can end up with the situation we are currently experiencing.
There are factors that exacerbate excessive thatch accumulation but for the most part its production is a natural process of highly maintained golf turf and some is necessary. But when it becomes excessive it has to be removed mechanically in a timely fashion through core aeration and de-thatching processes. These removal processes disrupt the surfaces we play golf on and get put off or minimized for a variety of reasons. The problem with this common approach of minimization or delay is the thatch continues to accumulate and then you inevitably have problems.
Some of these delay and minimization reasons are tournament scheduling, others construction and renovation busyness. The maintenance department admittedly got over extended on projects and over promised on putting surface performance abilities. Its not like we skipped scheduled greens aerations, we did not. We have just not been nearly aggressive enough with our aeration practices to keep up and deal with the thatch accumulation of the past fifteen years much less the past two where we have put more pressure on our greens to perform at a higher level. Our motives were to give you the fast and firm you desire however firm and fast are synonymous and trying to make our soft greens fast without doing what is necessary to make them firm is a recipe for mediocrity and potential disaster.
For the most part the greens at Granite Bay Golf Club have been aerated with ½’ coring tines with holes spaced 2”x 2”, two times per year for the past 15 years. This affected approximately 10% of the greens surface area per year with core aeration, which actually removed organic matter or thatch.
The USGA Green Section states “golf courses with successful, mature greens have been on a core aeration program where 15% to 20% of the surface area has been impacted each year.” “ The amount of surface area impacted is a direct result of tine size, tine spacing and frequency.” “If aeration has been neglected, a more aggressive program may be warranted.”
The USGA currently recommends 20% to 25% of the total surface area should be impacted annually due to modern putting surface demands and procedures to accomplish such demands.
Bottom line is we need to get more aggressive with our core aeration on our specified dates if we are ever going to produce the consistent firm and fast surfaces the membership desires.
We are in the process of getting physical soil testing done on our greens which will give us data for recommendations to proceed. I would not be surprised if we needed to effect 30% of the surfaces for the next few years to get caught up with accumulation.
We can achieve this by aeration with 5/8” coring tines spaced 1” x 2”, two times per year, in other words bigger and more holes. Additional procedures could involve deep vertical mowing which in combination with core aeration could really effect the surface area. What all of this will mean is a prolonged recovery time for the putting surfaces to completely recover after aeration.
Currently we have experienced some turf loss as a direct result of the thatchy conditions explained above and exacerbated by all the things we try to do to get speed out of them. We have a lot of loss around the perimeter of #14 green and some patches on #3, #13, #16 & #17. Additionally the customary summer thinning has taken hold on our #7 green. We plan to sod the rear perimeter of #14 and all of the patches on #3, #13, #16 and #17 by the end of this week. Additionally we hope to pick a morning in the next week and core aerate #7 with small coring tines along with light topdressing. Additional strategies to help us get through the summer will be a stepped up spiking events to all of the greens along with preventive fungicide applications to prevent disease in our susceptible condition. These short-term strategies are designed to help us get through the stressful summer without further turf loss. The long-term strategies of aggressive thatch removal by core aeration will be the key for our greens moving forward and need to begin this fall.
I believe we can have great greens here at Granite Bay however we cannot achieve this goal if thatch accumulation continues. Fast is directly correlated to firm and firm is directly correlated to an absence of excessive thatch. Even better the absence of thatch is directly correlated to a healthy condition that requires less water because the roots are deeper, less disease pressure because the green is healthier and fewer problems overall. Its that simple.
We’ll continue to address the greens situation in the course updates through the summer.
|Thatch induced anerobic black layer|
Recently sodded area on #14
|Patches sodded on #13|
|Front area sodded on #7|