USGA Article on factors affecting green speed

USGA COURSE CARE

Why Can't Green Speeds Remain Constant? June 17, 2016

Putting green speeds fluctuate because of factors such as temperature, humidity and the different maintenance practices.
                                   

It’s a beautiful fall day with cool temperatures and low humidity; you are playing golf and marveling at the condition of the course, particularly the pace of the putting greens. Some golfers might be inclined to just enjoy the moment. Others will wonder why the greens can’t play like this all the time. There are a myriad of variables that affect turfgrass growth and putting green speed; and, what is possible to achieve at one time of year under certain conditions may be impossible at other times.




Unquestionably, the biggest variable affecting turf health and playability is weather. Air and soil temperatures both have a tremendous impact on turfgrass growth rates. So do moisture and humidity. Rain or irrigation events, particularly when combined with a fertilizer application, can stimulate extra growth. This effect can be magnified under warm conditions with the result being increased surface resistance and reduced ball roll. Similarly, hot, humid conditions cause turfgrass leaves to retain moisture and remain fat, and this also may result in reduced green speed. Conversely, dry, windy conditions can cause the turf to wilt which can reduce surface resistance and increase putting green speeds. Putting green speed will vary from day to day merely as a result of weather influences and the seasonal changes turf undergoes.






Maintenance practices also have major effects on putting green speed. Mowing and rolling operations increase putting green speed. Applications of topdressing, needed to dilute organic matter and smooth putting green surfaces, can initially slow putting green speeds. A day or two after a topdressing application, putting green speeds often get faster than they were prior to the application. The same often is true of vertical mowing and brushing. Practices that stand the turf up aid in controlling the development of grain and can improve the quality of cut, but these practices can slow putting green speed for a day or two before stimulating an increase.




Many other factors affect turfgrass growth. Growing environments, soil conditions, and applications of plant growth regulators, plant protectants, and fertilizer are just a few. Anything that affects turf growth is likely to affect putting green speed. Golf course superintendents constantly juggle maintenance practices with the weather to maximize playability and maintain consistency. Despite our scientific training, modern equipment and experience, it is impossible to maintain a consistent putting green speed every day of the season.




The question is, why would we want golf courses to play the same way every day? Adjusting one’s game to the conditions and varying setup are some of golf’s greatest attractions. Golf courses cost a lot to maintain, and if consistency is so important, a cheaper alternative would be to move the game indoors. Golfers could use simulators and hit off of artificial surfaces into nets in climate controlled environments. This would ensure absolute consistency and eliminate the variable effects that come from wind, rain, temperature, maintenance practices, course set up, etc.




Fortunately, most golfers believe that playing the game outside in a natural setting is part of golf’s charm. Varying how courses play through setup and having to adjust one’s game based on the weather and playing conditions makes the game infinitely interesting and challenging. Rather than considering green speed and other aspects of playability as factors that should be kept as constant as possible, look at their changing effects as a blessing that continually adds interest and new challenge to a wonderful game.
 

Cart Restrictions - Cart Path Only Rulings

Lately with abundant rainfall I have been hearing a lot of questions about why we need to be cart path only when the course seems to be draining fine after the rain stops. I wanted to try and explain some of the issues involved in making the decision.

I don't ever want to inconvenience the members or take away from the enjoyment of your round of golf but CPO decisions involve more complex issues than most people realize. It's not about whether or not the carts leave ruts in the ground, but more about the long term health of the soil structure and turf. The time of year and number of rounds (carts) also plays a big part in how conservative I need to be. 

 

There are two main issues. When the soil is wet, especially on the surface, the water acts as a lubricant and allows the soil particles to compact more readily. This causes long term rooting problems as well as water infiltration problems during drier weather. When we were having dry weather back in July I was fighting a lot of these issues related to water percolation. We had a lot of localized dry spot (LDS) in high traffic areas. LDS occurs in compacted areas and the result is that normal irrigation water will not penetrate the surface and move down to the root zone. These areas then require wetting agents and manual watering which is a big job when it comes to fairways and rough.

 

The other issue during very hot and humid weather like yesterday (8/17/17) is called wet wilt and can be very detrimental very quickly. When you get a heavy downpour, followed by the sun coming back out on really hot days, the turf can't cool itself and everywhere a cart drives on wilted turf causes acute damage. Watching the radar and the storm forming yesterday, combined with high temperatures, I saw the potential for this to happen so I called it cart path only as soon as the rain started. Once the storm passed, and the threat for wet wilt passed, I reversed the cart restriction. During cooler times of the season I never would have taken action like that so quickly with just a brief rain event. We have had a lot of rain lately (10.6 inches in the past 30 days), so it wouldn't have taken much for that scenario to play out yesterday and I was overly conservative. 

 

In regards to areas getting damaged where carts can't go it's actually these same issues that contribute to those problems. Your feet actually have a higher PSI than your cart tires, plus spikes, so you will notice issues on tees and walk up areas to tees and greens due to wear and compaction even though there are no carts allowed there. All of those areas get traffic even when they are saturated and we are cart path only. Additionally, those areas do get traffic from all of the maintenance activities we do on a daily and weekly basis. These factors, combined with some disease and insect damage, is what led to turf loss on the tees on 4 and 6.

 

I'm sorry for any inconvenience these decisions cause. It's always a difficult one to make because I know that it detracts from the enjoyment of golf and makes the course play longer and harder.  As I said, I never want to inconvenience the members but I have to make sure the course remains in acceptable condition throughout the year.

LDS with wilted turf.

      

James hand watering fairway LDS in high traffic area on #1.

                      

 

Wet wilt with cart tracking at a local course. These tracks will turn brown a few days later.

   

Summertime Green Speeds and Height of Cut

Currently we are approaching the end of the "dog days" of summer. We are at the point where we can start to be a little less conservative with greens rolling, as well as start to lower the mowing height back to normal.

During the heat of the summer when higher temperatures and heavy downpours can come unexpectedly, we must stay on the defensive with our cultural practices. Rolling, brushing, and low mowing do damage that accumulates over time as stress increases and recuperative ability decreases due to high temperature and humidity.

Being that we are getting closer to when the turf can readily recover, I can start to push the greens more. In fact, we are planning on starting to roll some this week and lowering mowing heights gradually over the next 7 to 10 days...with the extended forecast calling for low 80's. We topdressed yesterday and John is grinding the greens mowers tomorrow in anticipation.

Currently, the greens are being mowed daily and we use a combination of growth regulators and light weekly applications of fertilizer to control growth. The speed is slower than usual due to the increased mowing height more than anything. During times of stress the height of cut is raised so the turf can produce more food for itself. Although it seems minor, raising the height from .110 to .130 creates a lot more leaf area for photosynthesis. Unfortunately that small increase, combined with the summer humidity, will cause a decrease in speed.

Last year I made the mistake of pushing for green speeds too hard and paid a price when the heat and humidity came and never let up. In that scenario the slow speeds came in late summer and fall due to the need to recover from summer thinning. I'm sorry for the reduction in speed over the last few weeks but our greens and collars have held up well for the most part and I think we are now out of the woods. That sets us up for a great fall season instead of pushing growth and recovery.

The speeds will increase over the next week or two leading up to aeration and then obviously they will be slower for a couple weeks after that. After they heal, you can expect them to get even faster throughout the fall season. We have been doing more frequent topdressing which will help with speed and firmness when the humidity and temps start to drop. We will also be doing a less aggressive aeration on the greens this fall so recovery time will be shorter than this past spring.


Thank you for your patience through this critical period of balancing health and playability.


For a detailed look at the science behind mowing heights please follow the link below.


USGA Green Section Article - Bent Grass Greens Mowing Height

Course Care - How you can help

As we get into the heat of summer and we are in our busy golf season the weather and player traffic can start to take a toll on the course. Our golf course consists of cool season grasses that flourish during the cooler parts of the season such as spring and fall but during the heat of the summer growth, and therefore recovery, slows down. Wear and tear starts to accumulate as growth slows and the turf has trouble keeping up until fall when it starts to grow vigorously again. During this time it becomes more critical to manage the wear and tear as best we can. There are many things we do in the summer to help the turf stay healthy such as plant protectant applications to prevent disease and insect infestations, light and frequent fertilizer application to help maintain optimal growth based on weather conditions, and good moisture management just to name a few.


There are a lot of things that the golfers can do to help out as well. The following pictures help illustrate the things you can do to help protect the course and why they are important.









DO NOT replace divots from Memorial Day until Labor Day. It is too hot and dry for the divot to root back in and it will die, taking up space and not allowing the surrounding turf to fill in as well. SAND ONLY right now please!

Please repair ball marks, even if you see one you didn't make. We repair them in  the mornings before mowing but they say that a ball mark will heal twice as fast if it is repaired within 10 minutes of being made. NEVER pry upwards or twist. The proper technique is to push down and into the center of the mark. You are trying to push healthy grass plants back into the center of the ball mark where the grass plants were smashed by your golf ball.

On the range please use a linear pattern for hitting balls. It uses less area and heals mush faster because the turf can fill in from both sides.

Please observe cart rules. Golf cart traffic can be very detrimental to turf that is under stress. Stress can come from being to wet, to dry, or too many carts in one area. When you see dry spots or areas where other carts have obviously been frequenting please try to avoid going through the same spot. "Scatter" is the best thing carts can do to help protect the turf. Try to drive over the best looking areas, not the worn ones. Nobody like the dreaded "cart path only" ruling but it is necessary in order to prevent damage to the turf. Although you may not see ruts, or damage like in the picture above from number 10, excessive moisture lubricates soil particles and increases compaction and damages roots which leads to problems when things start to dry back out.

Choose your shoes wisely: Thankfully this picture was not taken at Peninsula but todays selection of shoes that include some very aggressive spikes can be quite damaging to the greens. If you don't swing as hard as the pro's you probably don't need the kind of spikes they do. I love the non-traditional type of spikes but please try not to drag your feet on the green with any type of spike.

Spring Aeration and Bunker Update

This week was the first of our two aeration events on the course. Nine holes were closed Monday thru Thursday to complete aeration of greens and fairways. Typically, this process is done two times per year on greens, tees, and fairways using different methods depending on turf and weather conditions at the time. Over the past few seasons we have been making adjustments to our aeration programs in order to get the most benefit with the least disruption to play. For example, on tees we found that aerating in September during our scheduled closure, then again in November when play slows down, allows us to get it done twice without needing to do it in the spring. This strategy limits spring disruption while at the same time allowing more resources to focus on fairways and greens.


Unfortunately, conditions this week were pretty wet from rain last Friday and additional rains on Tuesday night and Thursday afternoon. This caused problems with getting a good core to pull out of the wet ground as well as getting sand to dry enough to backfill the holes on the greens. On fairways, not only do wet conditions cause problems with getting cores to pull good, the cleanup process is dependent on the cores drying enough to break up and blow or sweep off the fairway. Add in a few equipment breakdowns and it made for a long week. We will be working over the next week or two to finish up some areas so please excuse any additional disturbance. Although it is a lot of work and quite disruptive to play, aeration and topdressing are the two most important practices needed to produce healthy playing surfaces. The diagram below, as well as the link to the article from the USGA agronomist, give more information on the importance of proper aeration.



Thatch and organic matter accumulation in the upper soil profile is why aerate.

             
           http://gsrpdf.lib.msu.edu/ticpdf.py?file=/2010s/2010/100332.pdf








Our greenside bunker renovation is almost complete! McDonald & Son's has all of the greenside bunkers on holes 12 - 18 ready for the last steps in the renovation process which is polymer spraying and sand installation. In order for the polymer that binds the gravel drainage layer to be applied the gravel must be completely dry. Due to rain events and cool, damp weather over the last few weeks, we decided to wait and spray all of the bunkers at once instead of the original two phase plan. The current plan is to spray all of the bunkers on Monday the 10th if the gravel dries sufficiently over the weekend. After a 24 hour curing window, the sand will start to be installed. Remember, if you are golfing on Monday please don't go into the bunkers on 12 - 18. The polymer will ruin your shoes and the area will likely have to be repaired as well.


Thank you for your patience while we complete these critical course improvements!




Gravel layer after spray has been applied and cured.

Bunker Project Underway

McDonald & Sons golf course builders started work last week to complete the final phase of our greenside bunker renovation. Work commenced on the large bunker to the left of 12 green and by weeks end all four greenside bunkers on 12 and 13 had the old sand and drainage removed. Three of the four also had new drainage and the gravel layer installed. As you will recall from the past two years, the gravel layer will be sprayed with a polymer that binds the stone together creating a permanent barrier and drainage layer. We will notify you as to when this will be done because it is important to stay out of the bunkers for 24 hours to let it cure. Currently the plan is to apply the polymer in two phases, 12 - 15 when they are ready, then 16 - 18 upon completion.


The sand that was removed from the greenside bunkers is being added to some of our larger fairway bunkers. McDonald & Sons dumps the sand and our crew spreads and grades it. Although there is some contamination in the old sand, it will help in some of the fairway bunkers that are slow to drain or don't have enough sand depth. In the coming years we will be turning our attention to the fairway bunkers with our capital improvement plans.


Remember that all recently installed sand, whether it is new sand or old sand that has been re-used, will need some time to settle and firm up. Please enter and exit bunkers from the lower, flat side in order to not leave large foot prints. Even after the sand has settled, if you walk up a steep slope you will leave deep footprints. This is due to the angle rather than the depth of sand. All of the new bunkers are checked on a regular basis and maintained with a four inch depth. Occasionally, due to usage and maintenance, additional sand is needed in order to attain a four inch depth. Over the winter we added a couple of inches to some of the bunkers we renovated last year because there was less than four inches.

Excess soil being removed during demolition of old bunker.



Bunker floor being shaped after old sand and liner removal.

With dry weather this final phase of bunker work will take about four weeks to complete during which time the bunkers on 12 - 18 will be in various stages of construction. We will also be adding sand to and grading some of the fairway bunkers on 17 and 18. In order to keep making progress we will not be able to completely stop work for every group that plays through. Please pardon the disturbance while we complete this important course improvement.

Winter and Early Spring Update

It has been a mild winter and it looks like it's going to be a short one too. Warm temperatures last fall helped the course to recover from one of the hottest and driest summers on record. There are still some areas that need to fill in and the mild temperatures will help speed up that process. Spring has arrived early this year as well and we are seeing temperatures well above normal for this time of year. Although we will need to make adjustments to our plans to compensate it is a good thing to have more time to grow healthy turf before the heat of the summer gets here again.

Over the winter, the crew has been busy keeping the course playable for the mild days we have had while also finding time to complete some projects. Every winter, when the weather prohibits us from working out on the course, we bring in all of the course accessories and refurbish anything that we can. Yardage markers, cart signs, rope stakes, benches, bag stands, and trash cans all get sanded and a fresh coat of paint or stain applied.

When we can work outside and don't have course set up to do, we focus on cleaning up the native areas and the perimeters of the course. Over time, small trees and brush grow up along the edges of native areas and tree lines and they start to encroach on the course. This not only interferes with the playability of the course but shade, restricted air movement, and root competition also make for more difficult growing conditions for the turf. We have also been trimming areas where you have to carry native areas off the tee for a better view of the landing area such as on hole 8, 15, and 16. A lot of marsh and pond edges were trimmed this winter too for a cleaner, more maintained look.

Last but not least John Melson, our equipment manager, has been busy as usual taking care of the equipment when it's not being used as much. He spends a lot of time pressure washing, rebuilding, and sharpening in the winter as well as uses the down time to take care of some of the bigger repairs such as putting a new clutch in our older tractor.

Stay tuned to our new blog for regular updates as we move into the growing season. I plan on using this site to get a little more in depth information out to those who are curious as to what we do behind the scenes and why we do it. If you have any suggestions as to topics you would like more information about let us know. In the next couple of months we will have lots of topics to cover such as bunker renovation (starting this week), aeration, Audubon projects, and some very important spring fertilizer and plant protectant applications. See you out on the course!