A better method for firm

Drier, monitored greens mean firmer play and stronger root systems.We used to wear ourselves out managing the moisture in the greens.Like many superintendents, we subscribed to the deep and infrequent watering practice on our sand-based A4 creeping bentgrass greens. The day after the deep watering, our greens played soft and wet. The second day after our deep watering we would have a few small spots of wilt to hand water in the afternoon. The third day the greens would have massive amounts of wilt, and it meant we would drench or deep water the greens that night. This program would repeat all summer long. We would put a lot of thought into scheduling the deep watering around weekend play, tournaments, topdressings and ventings and it never worked out perfectly.

I didn’t think so at the time, but I know now that I was overwatering the greens, and wearing myself out in the process.

I was trying to put an end to this watering regime in 2007. At this time, I applying a pocket knife technique I learned from David Stone at The Honors Course (Ooltewah, Tenn.) and Nelson Caron at The Ford Plantation (Richmond Hill, Ga.). I couldn’t master their pocket knife system of checking greens. Instead, I turned to using a portable soil moisture meter. Christian Sain, director of golf course maintenance at The Country Club of Virginia, bought a ThetaProbe soil moisture sensor back in the summer of 2007. We loved the information it provided, but it didn’t prove durable to the number of times we were sticking it into the greens. We were on to something, but we still ended the year watering the greens “the old way.”

In 2008 we found a more durable probe. This probe could handle inserting it into the greens 60 to 70 times per green without bending. It would display the percent volumetric water content (%VWC) and it would keep a running average of all the spots measured on the green. We fell in love with the TDR 100 (3-inch probes) from Spectrum Technologies. These meters were expensive (about $700) and it was a challenge to find the money for them. I knew that these probes were going to help us deliver firmer, healthier and more consistent greens to our golfers. Fortunately, we work for a great club with a great membership that supported this concept.

In June of 2008, we started taking %VWC averages for each green in the morning and afternoon. Subtracting the afternoon average from the morning average indicated how much water the green used that day. At that time I thought I was doing well by being able to start the greens at 15 percent in the morning and finish the day at 12 percent. I later learned these levels were not something to brag about. By the middle of August we were starting at 12 percent and finishing at 9 percent. In September and October we were able to go even drier. We now target finishing the day between 8 percent and 9 percent in these months. The challenge was determining the starting %VWC. This part was trial and error, but we overcame this challenge by comparing the water use to the weather conditions. Studying this information and the weather forecast helped us determine the starting target %VWC.

Once we understood how to determine our target %VWC it was like making a dinner selection. However, we had to learn how to cook the dinner. Through trials, we found that our greens’ sprinklers would increase the average %VWC by 1 percent for every 1.25 minutes of run time. For example, if we finish today at 9 percent, and our weather predictions indicate we need to start tomorrow at 12 percent, then we run the sprinklers for 3.75 minutes. Weather forecasts do not always go as planned, and sometimes we miss our target and overcook our dinner. Hand watering is an ingredient in this program, also. Our sprinkler distribution uniformity is not 100 percent, and areas of the greens receive different amounts of water. Hand watering in the mornings helps us compensate for the uneven distribution.

When we take readings in the mornings, we identify areas below our target %VWC and mark them with a small irrigation flag. Flagged areas will receive a prescribed amount of water. About 60 to 70 readings are taken in the morning and 30 to 40 in the afternoon. Our hand watering process creates a very high level of consistency in the green. Local knowledge and experience is necessary to pick up on patterns that may not get probed. This part is what makes you a master chef.

The goal of maintaining the James River Course at The Country Club of Virginia is to be consistent from day to day. We want the golfer who plays on Tuesday to experience the same conditions as the golfer on Saturday. Achieving this practice with the greens was something I considered the most important part of this philosophy. We were not achieving a high level of consistency with the deep and infrequent watering regime. This new watering regime enabled us to create consistent moisture levels from green to green.

Firm greens are a component of what I would consider member/guest-like or tournament-like conditioning. Several things influence firmness, which are moisture content, materials used in construction and topdressing, organic matter management and grass type. Moisture content was something we knew we could influence on a daily basis. We found that 9%VWC on our greens was an ideal playability for our membership. At this level, a ball hit from the fairway with spin would bounce and stop, and a ball hit from the rough without spin would bounce and roll. The firmness helped put a premium on placing the tee shot in the fairway. I have learned that 9%VWC on these greens doesn’t always mean the same thing on another set of greens. This area is where the other factors of firmness come into play.

Now that we have a moisture management system for creating firm greens on a daily basis, it means improved playability. We hosted the Senior Open of Virginia, and these were the quotes from the Richmond Times Dispatch on Sept.24, 2010:
“The James River layout’s slick, speedy greens were the talk of the opening round,”
“The greens are really, really, good and really, really fast”– Allen Barber, competitor,
“You don’t get a chance to play greens this fast and this good often”–Tim White, head PGA professional Lake Chesdin Golf Club.

There are times we have to be careful with getting too firm, because we have golfers with a wide variety of skill levels. However, now we have a system that helps us determine these levels without making it a guessing game.

I haven’t come right out and said it, but hopefully you have realized that I am watering the greens every night. Everything I had been taught and read through my years of growing bentgrass greens indicated that deep and infrequent watering was the best way to develop deep roots and healthier turfgrass. In 2010, we experienced some of our best rooting during an extremely hot summer. In our system, we are creating the most air-filled pores possible without letting the plant wilt. I believe the more air in the soil, the better the roots will be as long as they have enough water to survive. The amounts of water we apply are just enough for the plant to survive the day. A deep and infrequent watering program creates a time where the pores are filled with air, also, but there are periods of saturation and inconsistency in playability. If we go two weeks without rain, we do a deep watering to keep the root zone from drying out at the bottom. We prefer no rain, so we can control the timing. The longer we go with our system in between rain events, the healthier our greens look.

When I look at the sprinkler run times under our old program versus our new program, we are applying 40 to 60 percent less water. I am proud to say that we found a way to conserve resources while making a better product for our membership.

I wish the program required less labor, but it doesn’t. In the first year there were only three people performing the functions of this program: two assistants and me. That year, 2008, was a learning year. We learned that two people in the morning and two in the afternoon was not enough. In 2009, we implemented three people in the morning and three in the afternoon. We also created an assistant in training position to allow us to perform the system on days when spray applications needed to be made. In 2010, we trained three other staff members to assist in checking the greens.

The program is very labor intensive, but we’re not wearing ourselves out managing the moisture in the greens anymore. My current assistants, James Nick and Matt Johnson, and former assistants, David Rathke and Adam Kerr, were instrumental in developing this program. In a short amount of time they have learned how to make extremely accurate watering decisions. This program will help them be extremely successful in their superintendent careers. It took me many years of wearing myself out before I discovered a better way, a way that allows us to deliver firm and healthy greens that golfers love.
 

Troy Fink, CGCS, is the senior superintendent at The Country Club of Virginia.