Turf conversion made easier

  • John Holmes
    Troon International

    Saadiyat Beach in Abu Dhabi used an interseeding process to convert its grass to Pure Dynasty

John Holmes
By John Holmes

With advances in turfgrass varieties and the ageing of courses built during the boom years of golf, it is not surprising that renovations involving turf conversions are currently on the rise. For these projects, the scope of work can vary. Some call for replacing turf throughout the course to upgrade to more advanced grasses. Others involve renovating select holes, and the opportunity is taken to update the turfgrass throughout.

Regardless of the scope, turf conversion through traditional sodding, sprigging or seeding brings challenges to the facility in the form of cost, time and interruption of play. For these reasons, the alternative technique of interseeding is gaining popularity.

Interseeding is the process of incorporating an advanced seed into an existing turf stand. With proper preparation, the newer, dominant variety overtakes the older turf for a gradual conversion. Through interseeding, the labour and expense of completely removing the old turfgrass are not necessary. In addition, interseeding requires minimal disruption to normal operations.

When Saadiyat Beach Golf Club in Abu Dhabi faced a recent shift in its irrigation water supply, the idea of turf conversion arose. Besides the need for a salt-tolerant turfgrass that could withstand the switch from potable water to treated sewage effluent water, wear tolerance was also a goal. In recent years, the bermuda fairways, surrounds and rough showed inconsistent performance due to higher levels of play during peak months.

Under the direction of Troon International, the maintenance team trialled different grasses and planting methods. The results led Troon to recommend interseeding with Pure Dynasty seeded paspalum.

“Pure Dynasty interseeding was chosen as a sustainable and low-impact way to introduce a more advanced turfgrass species to the property while still allowing daily play after the initial interseeding period,” said Bryan Cox, Saadiyat’s senior assistant golf course superintendent.

Saadiyat, designed by Gary Player and opened in 2010, is an award-winning championship course that has earned distinction as an Audubon-certified facility. The quality level and popularity of Saadiyat demanded that the conversion not only result in an excellent playing surface with advanced sustainability attributes but that it be done with minimal course closure time.

Preparation for interseeding started in June 2020 with an irrigation audit. While the new seed is drought tolerant when mature, success is maximised by keeping the soil wet during germination and establishment. Following the audit, a gradual scalping began, taking the fairways and surrounds from 12 millimetres to eight millimetres over one month. Next, the team applied a growth regulator. By the end of July, height of cut was five millimetres, and growth regulator was applied again. Thinning out the unwanted turf allowed the new seed to have direct contact with the soil for faster establishment.

At the beginning of August, seeding of Pure Dynasty began at a rate of 500 grams per 100 square metres. By the middle of August, the staff had completed seeding. Eight days later, the newly interseeded fairways and surrounds were mowed at 14 millimetres. A month later, the height of cut on the new turf reached the targeted 10 millimetres. The Pure Dynasty has now reached full coverage.

Whether a turf conversion occurs due to renovation work or simply to upgrade to a newer turf variety, interseeding allows projects to take advantage of improved turfgrass species without significant interruption. In addition to cost savings during the process, advanced seeded products offer benefits such as superior salt tolerance that translate into future savings.

When preparing Saadiyat ownership for the turf conversion, the maintenance team communicated the benefits of interseeding with an advanced turfgrass product, citing “playability, reduced water costs and a sustainability aspect while also having a limited impact on daily play,” said Cox. “Worth noting, savings in our annual water costs have been welcomed by changing to TSE [Treated Sewage Effluent] water while being able to continue to produce high quality turfgrass surfaces using the Pure Dynasty paspalum species.”

In the case of Saadiyat, interseeding provided the means to reach their goals, including “a more sustainable turf species year-round, in particular through the cooler winter months when golf traffic is at its highest,” according to Cox.

“Being able to reduce our chemical applications through this period has been a huge advantage to the property. We have also been able to give the Saadiyat Beach Golf Club members and guests a better golfing experience by providing a better playing surface.”

John Holmes is president of Atlas Turf International

This article first appeared in the October 2022 issue of Golf Course Architecture. For a printed subscription or free digital edition, please visit our subscriptions page.