Non-USGA greens on modern courses

[JBovay]

When should greens be built without adhering to the USGA guidelines?

Are there any (general or specific) methods to follow? Any resources that would provide details on the best way to do it? Are there one or two preferred techniques?

What modern courses don't have USGA greens?

JB

[MClutterbuck]

I am not an agronomist, but I can tell you agronomists and designer determined USGA greens were not in our best interest at course we are building on a very dry site, with cool summer nights and long dry days. At our site in particular, drainage is USGA specs but layers in between were altered. T1 Agrostis is being used.

[Jeff_Brauer]

To be honest with you, if you go by the actual letter of the law, most courses probably don't have USGA greens.

I have used California greens on many courses (pure sand) sandy topsoil on some northern courses, and mostly modified USGA greens in some way.  In a recent project, we just couldn't find sand that technically met USGA specs.  We did get as close as we could.  Besides actual changes to sand spec, you can eliminate the choker layer (very common) change depth, etc., etc. etc.

I usually look for percolation and retained moisture properties that approximate USGA specs, but use some common sense. In dry climates, I would tend to lower perc rates and higher retained moisture, and perhaps the other way around if there was a cool climate and perhaps poor water quality (an increasing problem)

Like I say, the original spec was to find a way to use local sands to provide a lower cost improved putting surface.  Over 50 years, it seems to have evolved into a narrower and narrower guideline, via USGA research, but I never fear using a bit of common sense to get what seems to be appropriate growing conditions for a particular site.

[Tom_Doak]

When you are building in good sandy soils, USGA construction is not necessary, nor is even a California system with basic drain lines under the greens.

Among the courses I've built that are built with native soils and no drainage:  Lost Dunes, Pacific Dunes, Old Macdonald, Barnbougle Dunes, Ballyneal, Dismal River, and Streamsong (Blue).

Many Coore & Crenshaw courses are also built without drainage under the greens, including Sand Hills and Streamsong that I am sure of.

[Greg Chambers]

You've been lucky to build on some fantastic sites, Tom.  As far as the USGA greens question, I'm of the opinion that it's not necessary.  If you can find a well draining soil either on site or nearby, use it...and put some drainage in underneath.  USGA method is good for driving up the cost of construction...beyond that, you'll never know the difference.

[Jon Wiggett]

I prefer FLL German system which puts main emphasis on percolation rates. It allows the sensible usage of local soils which allows for a deeper root zone to be built above the drainage layer. USGA system has its place but it is definitely not a one stop solution.

Jon

[JBovay]

Thanks, gents. I have been wondering about the necessity of USGA greens for a long time. I knew that they were not necessary on very sandy sites, but did not realize how common it is to build greens that don't quite match the specs.

Jeff, when you are trying to determine which hybrid system to implement, do you test the physical properties of the different options (with regard to both soils and layers) using some kind of small-scale test sites/plots?

Tom, when you built the greens at the courses you mentioned, was it as simple as shaping, irrigation, and seeding?

[Tom_Doak]

Tom, when you built the greens at the courses you mentioned, was it as simple as shaping, irrigation, and seeding?

Sometimes yes, sometimes no.  It depends on how much variation there is in the soils across the site.  The superintendent wants consistency, so if there is too much variation, it may be necessary to mine sand from one location to use for some or all of the greens.  [Little known fact:  the source of the sand for Bandon Dunes' greens was the road cut through the dune that eventually became the access to the Pacific Dunes clubhouse.  However, that did cause some problems, because there was much more organic material at the edges of the greens than in the greens mix taken from deep in the dune.]

Most of the courses I mentioned, the greens mix really is just whatever existed at the green site.

[Mike_Young]

Growing bentgrass in the South almost always required a USGA spec green or at least a root zone that met the USGA specs for a rootzone.  However, with the advent of the ultradwarf bermuda grasses this has all changed.  Some older greens that would not work for bent are great for the bermuda.  It is another benefit of replacing bent with ultradwarf..

[Jeff_Brauer]

Thanks, gents. I have been wondering about the necessity of USGA greens for a long time. I knew that they were not necessary on very sandy sites, but did not realize how common it is to build greens that don't quite match the specs.

Jeff, when you are trying to determine which hybrid system to implement, do you test the physical properties of the different options (with regard to both soils and layers) using some kind of small-scale test sites/plots?

Tom, when you built the greens at the courses you mentioned, was it as simple as shaping, irrigation, and seeding?

It is rare to have the time to plant any sort of test plot based on different soil types.  Besides, the value of a good greens mix would never be proven over 6-12 months, more like 6-12 years.  So, we base it on soil testing of whatever soils we happen to be considering.

Of note, when I built Lake Arrowhead for Killian and Nugent, right next to the proposed Sand Valley site, what little topsoil we found had 3% organic, while the underlying sands were almost pure.  We mined and hauled that topsoil to greens to hold just a little moisture, and did cut a USGA type greens "dish" to hold that soil, which necessitated what we called a "bird's foot" of tile drains at an green swale exit.  All that was based on soil testing and recommendations by the originator of the USGA green, Dr. Marvin Ferguson down in TX.   The fairways remained pure sand, but in planting the bent grass for both tees and fw, we added lots and lots of Milorganite as a seed carrier/organic element.

We also mined sand at the Quarry up in MN ten years back.  I do recall that there was some discussion, and it was very nearly a cost balance between buying from a pit that had already screened a similar sand vs. mining, screening rocks, etc. from the site itself.  In addition to rock picking native soil, and root picking, if you decide you need to blend in some amendment, it is also easier to do that on a flat paved surface, which you would have to create on site, while the sand pit probably already has that surface for other operations.  Obviously, trucking to the individual green sites is less expensive from one side of the site to the other, over hauling 20 miles or whatever.  Sometimes, the apparent cost savings of on site sand are a bit iffy.

I agree with Greg that TD has had some amazing sites over the years.  For most of us in the biz, running across natural sand sites is a rare event, and more care must be given to building the greens, and so rare in fact, it wouldn't be on the top of the minds of most of us to even mention the rare special cases he did!

[Angela Moser]

Is there an agronomist out there who can explain when which construction is more preferable over the other? USGA, California, FLL, dirt greens.... when do you choose which? (Beside the perfect natural sand site without any drainage problems) which is the most expensive?

Tom: How many California green construction sites did you have yet? Is that a common option?

[Jeff_Brauer]

Yeah, but some make making the decision seem extremely complicated a science to stay in biz, so I doubt you will get an answer here.

Besides, it can be complicated.  Most architects will prefer an approach of "every site is different in its climate, micro climate, etc." too.   And most of us are forced to for budget reasons.  I don't know about TD, but I have built perhaps 20 sets of CA greens, probably as many "modified" USGA greens (which the USGA will tell you are not USGA method) and only a dozen or so pure, full to spec USGA greens.

Mike Hurdzan probably did more than anyone to popularize CA greens, and later flat tiles vs. trenched in 4" drains embedded in gravel.  CA greens cost less, to whatever degree 2500-3000 tons of gravel for the 4" pea gravel layer in a USGA green costs.  It used to be you could get 1/4" pea gravel for under $20 a ton.  Now its double that so using a CA (or any) method that eliminates that saves up to over $100K.  USGA research did show that the gravel layer evened out drainage, and may extend green life, but in reality, a tight budget project may have owners who won't be around in 15 years to see consequences, if any.  It is often an easy cut, and hard to detect.  At the same time, most courses are loath to go pure sand (which is high perc, and works best where water is crappy) so many build CA greens with USGA style sand/peat mix.

I do believe in the sand based green.  They were developed because sand doesn't compact (in theory at all, in practice much less than clay or silt) and compaction kills greens.  They use more water and fertilizers, but after the 1960's or so those could be replaced via irrigation and ferts while compaction remained a problem.  So, sand greens it was and mostly is.