Keith Osterman allowed himself the luxury of exhaling recently when the almanac revealed that the number of daylight hours had finally ticked below 14.

Then he quickly went back to biting his nails and riding the knife edge as golf course superintendent at Beacon Ridge Golf and Country Club in West End.

This summer’s heat has Osterman and his colleagues across the Sandhills sweating like never before for simply trying to keep their putting greens alive.

“It’s the worst summer I can remember,” he said, casting his mind back over 20 years of growing golf course grass in the Carolinas. “They said on the news the other night that we’ve had record average highs for May, June and July, but I really didn’t need them to tell me that.”

At nearby Mid South Golf Club, course superintendent Rusty Smith has seen the roots on his Penncross greens shrink from a healthy six inches in May to an inch or less now.

“And August is still ahead of us,” he said. “This kind of sustained heat is very unusual. It’s certainly the worst I’ve seen.”

Bentgrass, the fine-bladed turf favored by the vast majority of courses in the Sandhills for the smooth putting surface it provides, is best-suited to temperatures far below those those cooking the region this summer.

Superintendents generally expect problems into August, as the range of stresses that heat can inflict begin to add up. But things have been so intense since so early this season that most superintendents have exhausted their armory already, not to mention their crews.

“I’ve definitely been keeping guys on longer trying to do all we can stop the heat killing us off,” Smith said. “We’ve definitely got some thin greens, and we’ve had some bouts of pythium root rot.

“We’re living day to day.”

Among the weapons Smith and other superintendents are employing is a practice known as venting. Various tools such as bayonet tines or pencil tines are used to pierce the green surface promoting the passage of air and nutrients.

“Anything to help them breathe,” Osterman said. “But what are you gonna do when you get a two-inch thunderstorm and the heat index is 105 degrees?

“My greens are stressing, but we haven’t lost a lot of grass yet, touch wood. I guess we’re doing OK, but I know a lot of guys are struggling.”

The situation is similarly challenging in major centers such as Charlotte, Greensboro and Raleigh.

Indeed, some courses in those areas have been forced to close temporarily while their greens are regrassed.

“We will probably do some interseeding in August,” Smith said, describing a practice where a different grass variety is mixed with the existing stand. “Anything to get some more grass in there.”

Smith said he will likely sow Crenshaw bentgrass with the existing Penncross because of the relative resilience Crenshaw has shown across the road at Talamore Golf Club.

“Hopefully, the Crenshaw will provide a little more heat tolerance,” he said.

Syringing — spraying a light mist to cool greens — is another critical practice right now. Golfers may experience brief delays while golf course maintenance staff perform this hand-watering, but without it, greens could very easily and quickly die off altogether.

The margin between plant survival and outright failure is so thin currently that Osterman said, “The only people on my crew that I trust with the syringing are me and my assistant superintendent.”

That makes for long hours, sometimes stretching his standard pre-sun up start to 7 p.m. or later.

“Normally by 3 p.m., you’re pretty good to go,” Osterman said. “But the other weekend, if I’d left even at 4 p.m., I know the greens would have gone belly-up.”

Superintendents may not be the only ones holding their breaths in this heat.

Doubtless there are some at the United States Golf Association already crossing their fingers for kinder conditions in 2014. That’s when the USGA will stage the U.S. Open and U.S. Women’s Open championships a week apart at Pinehurst No. 2.

A repeat of this summer’s brutal pounding could create an insurmountable challenge.

“There’s only so much we can do,” Osterman said. “Mother Nature always has the ultimate say.”

Contact Trent Bouts at (864) 414-3123 or e-mail trentb@charter.net