Relocation of our primo Zoysia grass

The primo Zoysia from the second green and the back of our nursery (current temporary second) have been lifted and relocated to our chipping green (next to the first green). An apron of sir grange Zoysia has been placed around this chipping green and a growth blanket will be put over it shortly to keep warmth and encourage knitting and growth. Members are encouraged to have a look at this green when they go past and feel the differences in the surface between these grasses, the surrounds and the current grasses on the first green (bent/poa)

This further enhances our trials on site to see how the zoysia grasses cope with full shade on the front half of this green and full sunlight on the back half. It furthers the data we have on this grass in all growing conditions and under duress in different locations on our property. Initial reports are what we have been told in that it is a very resilient grass which copes better under stress than our current surfaces.

If anyone watched the recent USPGA championships at Valhalla, it’s interesting to note that they have laid this exact grass (Zeon zoysia they call it) on all tees, fairways, and surrounds. It did look beautiful on the television.

Data from Zoysia trials

Our trial on Zoysia grass has been ongoing for almost three years now. We have had ‘Trinity’ Zoysia on our practice putting green since 2021 and ‘Primo’ Zoysia on the back of the second green and the nursery green (current temporary second green) has been down for over a year now.

We have conducted various experiments to investigate changing the playability of the surface, test growth in shade and test with our current bent grass irrigation schedules and reductions thereof, along with testing how current maintenance schedules effect the surface (spray schedules, dusting, scarifying etc). Below is a list of pro’s and con’s about Zoysia grasses we have discovered over the three-year journey.

Pros

Very drought tolerant grass (both primo and trinity varieties).
Uses 50% less water during peak season.
Uses up to 60% less chemicals during peak season
Consistent green speeds in both the growing season and during dormant periods
Improved coverage year-round from current Bent/Poa greens
Deeper root structure than Bent/Poa even in current subsoils (4 inches +)
Disease tolerant and less susceptible to encroachment grasses
Stood up against the weevil infestation this year in the Bent grass greens
Was not affected by black Beetles this year also in bent grass greens
Can take cuts at lower heights even under stress (2.5mm) compared to our bent greens at 3.5mm
Potential green speeds of 11+ on the Stimp meter
Potential less need for invasive renovations (currently twice per year)

Cons

Very tough grass if the subsurface dries out
Can be quite noisy with ball roll
Hard to hold greens when firm and fast
Putts tend to follow grain
Colour changes during winter (browning off)

Over the last 6 months we have ramped up the testing on the Zoysia grasses. Any damage that has been visible in any of our Zoysia greens has been part of our data capture. All tests were conducted in consultation with experts in the industry and consultation with various published reports from other countries, to determine the optimum maintenance program for our environment. To test the resilience of the Zoysia grass over the last three years, we have basically tried to throw everything at it we have experienced over the 90+ years on site.

The green staff used multiple preparation trials to change the playability of the small footprint on the back of the second green. Regular players when the Zoysia was in play would notice the increased bounce in this section of the green. Wedges were hard to hold on the small footprint on the Zoysia surface. To change the playing characteristics, this green was cored, double scarified and dusted regularly. This patch was put under great stress to test its resilience to greenkeeping techniques and to see how easily/quickly we could change the sub surface and soil content. As this variety of Zoysia was completely new to our property there was always going to be some trial and error to test best subsurface, best practice and what it likes and didn’t like.

Results from these tests proved significant in that the playing surface changed to being more receptive, spin was achievable on wedges into the green and the surface had some give when walking on it. Playability however was not as good as the test patch on the nursery green (also located on the second hole).

On the nursery green subsurface structure, soil content and moisture levels were monitored over several months. The sand/soil mixture on the nursery green is different from the rest of the course and turned out to be much closer to a USGA spec recommended substructure for a putting surface. The soil here holds more moisture and is an appropriate mix of sand, soil and organics to promote the best environment to grow Zoysia Primo grass. The primo zoysia on this green has thrived through the 12-month trial and now presents a significant improvement over the back of the 2^nd green.

The grass on the nursery second green produced a deep green coloured receptive but hardy surface. The grass leaf here lies horizontally instead of standing straight up as it does on the back of the second green, producing a surface conducive to balls which spin and stop within tolerable distances. In our opinion the surface now surpasses any other putting surface on the course.

However (there is always a “however”), the nursery green has yet to experience any significant foot traffic and consequently there is very little damage from passing golfers. This is another reason for the relocation of this grass to the chipping green (side of the 1^st hole) to see how it fairs under more duress. Even though it’s only been down a relatively short period of time its already kicking back and thriving with a bright green colour. We believe this will be a far superior all round surface to what we currently have on offer.

The results of our tests on the Zoysia Primo can be summarised below:

It likes to be left alone (it will require less aggressive physical and chemical maintenance)
It thrives with regular mowing
It performs best with a small thatch layer in the green
The deep root zone is imperative to maintaining the desired playing surface (e.g. less pitch-mark damage).
A good mixture of sand/soil is required to get the ideal ‘bounce’
While this surface requires less hand watering during peak season, subfloor moisture levels should be monitored regularly to ensure consistent bounce on the playing surface.

Outcome

The Board of Directors has decided to implement a replacement program for the Bent/Poa winter grass greens with Zoysia (primo), a summer grass. The Bent/Poa greens do not cope with high volume traffic. They also do not cope with the heat and high humidity that we experience in summer. In the post-Christmas period we are constantly dealing with severely distressed greens and trying to keep the surfaces alive. Bent/Poa greens require a huge amount of water and an ever-escalating chemical cost.

We have learnt what the appropriate greenkeeping practices are for properly maintaining Zoysia grass, what the irrigation requirements are and what maintenance schedules to apply and when. We are confident using this knowledge we will be able to maintain the longevity of the new putting surfaces.

The second green will be the first green to be replaced under this program. The reason for a full rebuild is to properly implement our replacement specifications with the best growing conditions using the knowledge gained from our tests together with additional research and expert advice. As has been discussed in previous communications, most of our greens are over 40 years old. They are mostly “push ups” using materials which were close by which was the practice when they were built. The problem that has evolved is that they were only designed to accommodate 25,000 golfers per year and only for a short time.

Our success as a club is also what has led to the detriment of our current putting surfaces. We now facilitate up to 70,000 rounds of golf per year, plus cart traffic, heavier green staff machinery, expanding microbe infestations, increasingly saline dam water and 40 plus years of wear and tear.

The inescapable conclusion is that we need to change our playing surfaces to accommodate all year round play and set the course up for the next 40 years. The Board is convinced that that change is Zoysia.

Timeline

Timeframe for the project on the new second green is between 16-24 weeks, subject to finding any gremlins in the ground or delays with equipment/supplies etc.

Regular updates will be sent to the membership along with some pictures over the timeline.

A lot of eyes are on our golf club now and there is a lot of chatter in the industry about these types of grasses and the benefits in the long term to golf clubs. Please take care when walking past the course works in the meantime and please encourage our team of dedicated greenstaff in their efforts on course.

Greens Committee

On Behalf of The Board of Directors

Gosford Golf Club