What Is A SubAir System On A Golf Course?

It’s a term you might well hear during Masters week, but what actually is a SubAir system and how does it help keep greens consistently good?

What is a subair system
An additional SubAir unit working hard in rainy conditions
(Image credit: Getty Images)

A SubAir system is an underground system used by high-end golf courses such as Augusta National (generally on the greens) to regulate moisture levels and provide aeration and heat control, allowing greens teams to maintain green condition, no matter what the weather is doing.

You may hear the system mentioned at The Masters.

According to SubAir, their systems provide “aeration, moisture removal and root zone temperature control in order to create an optimal subsurface growing environment for deep-rooted, resilient, healthy green grass.”

In rainy conditions, the SubAir system can remove water from the playing surface, drying greens far more quickly than they would dry naturally.

In drier conditions, the SubAir system can be used in pressure mode to deliver air to the root system below greens, improving growth. For the most part, this is what the SubAir system will do – create an optimal growing environment.

But when the heavens open, it’s an invaluable tool for getting play underway again as quickly as possible.

How Does A SubAir System Work?

A SubAir system can be installed into the existing drain system of a USGA specification green meaning there will be little impact in terms of excavation and rebuilding work if a course decides to have one installed.

A vault containing a blower unit is installed at the greenside which can be set electronically to function either in moisture removal or pressure mode.

In the former, water and air are sucked through the turf by the blower – water goes into the drainage system and away through the greens natural drain routes while air is sucked into the vault and then above ground.

In pressure mode, air is pushed up through the soil to optimise growing conditions with aeration and temperature control. Greenkeepers can monitor levels of moisture, aeration and temperature and set the unit to function accordingly.

Are The Greens At Augusta Heated?

Sort of – A SubAir system can be used to control temperatures in the root zones which can help to extend the growing season beyond normal seasonal variations. The pressure mode of a Sub Air system can also be used to cool the root zone in particularly hot weather.

By moderating moisture, temperatures and aeration levels effectively, the root zone will be healthier and the grass more resilient as a result. That will create a more consistent, smoother playing surface. Turf will also recover more quickly if it incurs heavy traffic.

Augusta is by no means the only golf course to utilise Sub Air technologies. Courses including Wentworth, Adare Manor, East Lake, Colonial, Sentosa and Quail Hollow all use SubAir systems. As do a number of sports stadia around the globe.

Fergus Bisset
Contributing Editor

Fergus is Golf Monthly's resident expert on the history of the game and has written extensively on that subject. He is a golf obsessive and 1-handicapper. Growing up in the North East of Scotland, golf runs through his veins and his passion for the sport was bolstered during his time at St Andrews university studying history. He went on to earn a post graduate diploma from the London School of Journalism. Fergus has worked for Golf Monthly since 2004 and has written two books on the game; "Great Golf Debates" together with Jezz Ellwood of Golf Monthly and the history section of "The Ultimate Golf Book" together with Neil Tappin , also of Golf Monthly. 

Fergus once shanked a ball from just over Granny Clark's Wynd on the 18th of the Old Course that struck the St Andrews Golf Club and rebounded into the Valley of Sin, from where he saved par. Who says there's no golfing god?