Wednesday, 15 February 2012

Rethinking Sand Trap Maintenance

Today I had a very interesting conversation about "minimalist" sand trap maintenance with a few fellow Superintendents on Twitter. Many golf clubs these days spend as much if not more on their sand traps as they do their putting greens. I decided to stop and think about each aspect of sand trap maintenance and ask why we currently do what we do, what alternatives there are, and what is best for my golf club.

Sand trap raked with Sandpro. Edges done by hand with a rake.
The first and most obvious maintenance practice is raking the traps.  The purpose of raking the traps is to smooth and loosen the sand to try and provide consistently soft but firm sand. Good luck with this! 

Most courses these days use motorized bunker rakes due to the speed and economics they provide. Simply put they are many times faster than raking traps by hand. They do require a large sand trap though so the smaller traps will still need to be raked by hand. Personally I do not see the advantage of hand raking sand traps especially when are looking to save money on maintaining your sand traps. The biggest part of most budgets is labor and hand raking traps is many times more labor intensive than using the motorized trap rake.

Even with the efficiency of the motorized trap rakes we are still faced with having to rake the edges of the sand traps. Most courses that I have been to use rakes to pull the sand from the bottom of the edges up towards the sand trap lip. I can't remember where I saw it first but sometime last year I saw a video clip of greenkeepers using brooms to push the sand up the slopes on the edges of the sand traps. At first I thought nothing of it but after talking with those Superintendents on Twitter this morning it hit me! 

It all boils down to what we as greenkeepers and everyone else as golfers want in a sand trap edges. As a greenkeeper we want a surface that is easy to maintain. Golfers want a sand trap that looks good as the designer intended (some traps are made to look "natural" and some are intended to look clean with well defined edges. See the Anarchist's Guide to Golf Course Architecture.), a surface where balls don't plug but is soft enough to swing a club through, and usually a lie in the trap that is on the bottom (flat) portion of the trap.

We as greenkeepers are constantly battling to keep the sand up on the slopes. We have to sometimes daily rake the sand up the slopes to keep the sand depth consistent. Now ask yourself, Is raking the sand really the best thing to prevent erosion of the sand? Does it make any sense that by loosening the sand will help it stay on the slope?

Another question is do we want sand that is that loose on the bunker slopes? Do golfers like hitting out of plugged lies on the slopes of the traps? So why do we constantly loosen up the slopes with rakes?

The purpose of raking is to pull or push sand up the slope, and create a clean and consistent look.  It also servers the purpose of disturbance of the sand keeping weeds at bay (for the most part).

If we use big push brooms to groom the edges of the traps we can solve many of the problems that hand rakes present to sand trap maintenance.  Firstly they are capable of moving a lot of sand and sometimes more than a conventional sand trap rake. Personally, I have my crew rake the edges of the traps from the inside of the trap before we rake the bottoms. This is easier on the back, gives them a better view of the edge, and helps prevent them from pulling excess sand up on the trap lip. It also keeps the operators on the motorized trap rakes from driving too close to the trap edges as they are already groomed when they rake with the machine.
Edges are groomed with the broom first

Secondly they do not disturb the sand on the slopes of the trap.  This is important for a number of reasons.  It minimizes erosion and provides a firm surface which will prevent plugged lies due to the more compacted less disturbed sand. This firm sand will allow the golf balls to roll down to the bottoms of the traps. This undisturbed sand will remain in place for longer and will eliminate the need to irrigate your sand to keep it firm.  Undisturbed sand will hold the moisture longer and will be more consistent. Furthermore this more compacted sand on the trap edges will not be damaged as much when golfers decide it is a good idea to climb out of the trap up the steep bunker slope.

Thirdly it provides just enough disturbance to prevent encroachment of weeds. Depending on the desired look to the edges of the sand traps it would even theoretically be possible for the edges to only be raked every other time that that the bottoms are raked. This is another potential labor savings.
Then the bottoms are smoothed out with the Mechanized
Bunker Rake

Fourthly (is that a word?) they are quick.  It is easily twice as fast to broom the edges of the traps as it is to rake them.  It provides a very consistent and clean look that is difficult to achieve with a rake. Further experience is needed to determine which broom is right for your situation.  Wide brooms are good for doing the edges of traps that are rather straight.  For twisty edges a narrower broom might be better.  We also have the options of bristle stiffness.  Again trial and error will best determine which style of broom is best for your sand traps.
Nothing fancy here, old push broom, 1988 Sandpro 14
Other issues associated with the extreme cost of sand trap maintenance have nothing to do with the sand itself.  A great deal of effort is spent on keeping the turf surrounding the traps alive.  Wetting agents are often sprayed to keep the soils uniformly wet due to the constant spraying of sand from out of the traps.  Special irrigation head are installed to allow for these areas to be watered separately from the rest of the course.  Perhaps a more sustainable or "minimalist" thing to do is evaluate the species of turf or plant that is used to surround the sand traps. Is ryegrass or bluegrass the best species to surround a sand trap? What about introducing fine fescues or.....get ready for it.....white yarrow?



Yeah, that's right, white Yarrow or Achillea millefolium. "But isn't yarrow a weed?" you might ask. Well yeah, most greenkeepers do in fact consider it a weed.

I first heard about the use of white yarrow from Armen Suny from Zokol Golf Design LTD. He is also the author of the blog "Anarchists Guide to Golf Course Design"http://aggca.blogspot.com.

He was presenting his thoughts about minimalist golf course design specifically at the Sagebrush Golf Course near Merritt B.C. Unfortunately a lot of the really great things he had to present were lost in the controversy surrounding some comments made is some newspapers somewhere about things that guys apparently do or something. Who knows? Being the way I am I ignored the BS and tried to learn something.

He talked about how they used a mixture of fine fescue and yarrow on their bunker edges and on some areas of their fairways. Apparently it isn't bad to golf on, has great color even during drought and tolerates the sandy conditions of the bunker edges. He talks about its use on this blog post about a mile down the page.

Another huge benefit of yarrow for sand trap edges is its rhizomatous (totally a word, I looked it up) growth. It throws down rhizomes and will tightly knit the edges of your traps together to prevent erosion and hold everything together.

It might seem crazy to seed the edges of your traps with a "weed" but what it really comes down to is, how does it look, how does it play, how much maintenance does it take. Apparently it looks good and green even during drought, plays as good as anything, and requires almost no maintenance. Now THAT is minimalist! Just be sure to keep the herbicides away from this stuff!!

I know a lot of what Armen presented as minimalist can be debated but the use of white yarrow on bunker edges is genious. Another thing I will be implementing this year on my traps. Thank you Armen!

Another thing I like to do on the traps at Pender Harbour is to keep large lips on them. This minimizes encroachment of the turf into the traps and helps me maintain the edges with a string trimmer. Again it all depends on the look you are going for. No matter what look whether it be laser clean lines or rough and rugged, the edges of your traps can be "minimalist". Sloppy looking traps can be a lot of work, tidy traps can be a breeze to maintain. Work smart, not hard.

Winter maintenance is also an issue. During this time of year on the West Coast it is often very wet and there is minimal play, if any. One thing that works great is to enact a lift rake and place policy. That way the golfers always get a good lie in the traps during the winter but you won't have to rake them as often if at all.

So to summarize my thoughts on minimalist maintenance of bunkers, use motorized rakes when possible, brush the slopes of your traps to increase playability and plant appropriate plants on your bunker surrounds to minimize inputs and optimize the look and playability. There is no reason why sand trap maintenance should even be half the cost of maintaing putting greens. Maintenance of the sand traps at Pender Harbour is 7x less expensive than maintaining our putting greens before using these potential cost saving strategies.

Please let me know what you think and I look forward to hearing about everyone's experiences with minimalist sand trap maintenance.