OK Im back and all jacked up on Mountain Dew, coffee and dip....Ill try to catch up on some questions asked to me. Watch out Patrick!
I was thinking about this all night and Im pretty sure it was the last thing I thought about as I dozed off. Its like counting sheep. This is my first thought....
We need to stop looking at the different greens construction methods and the materials associated with them as "brands" and start
thinking of them as simply "growing mediums". I really sense a tone of disdain when it comes to USGA spec greens, and I think
there is more to it than the greens construction method and materials they recommend. Is it possible, bare with me on this, that we
often hear these negative tones because of personal opinions about the USGA as an association in general? With some of the drama
associated with them in the past few years with the 2004 Open or the Walter Driver era, could it be possible that emotions or opinions
are spilling over into their agronomics? Is it a bad thing that the "USGA green" has the name "USGA" slapped on to it? Almost as if
the method has been branded and the common consumer ( club member, super, avid golfer, whatever) has come to despise the
USGA's research and recommendations? I think so and feel this may make for a thread topic.
But back to different greens construction methods and the common opinion of them...
USGA greens construction materials are not purchased from Far Hills, NJ and they do not come in a box with the USGA brand name on
it. The USGA, as we all know, simply funded a tremendous amount of research on new greens construction methods since the 60's.
Experimenting with different materials I believe they started with a few concepts that they held true.
1. The game of golf and golf turf began in the sandy linksland on the UK coastlines, turf already revealed what it likes to grow on.
2. Greens not only needed to drain on the surface, they needed to be free draining through the profile. And I think they were seeing
the most successful greens being the push-up greens that were built on sandy sites such as Shinnecock, NGLA etc.. I would
also bet that they were seeing the less successful greens being more inland that utilized the heavier soils with a clay content.
3. With the most successful sand based push-ups Im sure they were seeing a problem with nutrient retention and efficiency when
compared to the inland soil push-ups with a higher organic matter content.
(None of these are anything factual that I got right out of the history books but I think its some pretty good speculation as to
how a USGA green concept evolved.)
I think that it is very basic knowledge that grass likes to grow in an enviornment that is not compacted, fairly drains and contains some
organic matter content. THIS IS WHAT THE USGA GREEN ACCOMPLISHES. The USGA green IMO is the best of the 2 other extremes
that are also the 2 other popular methods of green construction. The California Green and the soil push-up green.
The California Green works, and it can work very well. And there are many California Greens out there that are proven successes. But
Ca greens are straight sand, no organic content. And the first step towards success is with choosing the right sand. But even if the
right sand is used and it drains very well there is an issue with its nutrient retention and efficiency. Supers could find themselves
fertilizing with higher rates or at increased frequencies because the CEC of straight sand is naturally very low
Just like a super with soil greens is always aerifying and sanding the greens to improve drainage, a super with a Ca green is always
applying organics to increase nutrient retention and efficiency as well as WATER retention and efficiency. A Ca green can drain
TOO GOOD. The application of organics will make water and fertilizer use more efficient and cost effective. You could also include
the increased use of expensive water retention wetting agents.
On the other end of the spectrum is the soil push-up. Soil obviously has better nutrient and water efficiency characteristics than
straight sand because of its organic content which lends to a higher CEC. The problem with soil is that it has a naturally higher
bulk density, meaning it is very compactable.
As bulk density increases....
1. Pore space for healthy root growth decreases
2. Pore space for water infiltration decreases
3. Pore space for oxygen and carbon dioxide exchange decreases
So lets compare the 2 ends of the spectrum, soil push-up vs. california, but lets avoid any "branding". So lets use.....
DIRT vs STRAIGHT SAND = COMBINATION
DIRT STRAIGHT SAND
Excellent Nutrient retention (hi CEC) Poor nutrient retention (low CEC)
Excellent water retention Poor water retention
High bulk density (compaction) Low Bulk density (no compaction)
COMBINATION
Excellent nutrient retention (high CEC)
Little to no compaction (low bulk density)
Excellent water retention (micropores)
Excellent water infiltration (macropores)
Its obvious that the combination is what resulted as the USGA spec green. Its also obvious that what was achieved by the USGA's
research is a specification that takes the best attributes from the soil and the sand which is the addition of certain percentages of
peat to a straight sand that is spec'ed to achieve good drainage. The end result is a growing medium that balances everything
needed in an optimal grass growing enviornment.
We also need to look at what the gravel layer is used for and why it is so crucial to USGA spec success...
1. The gravel layer primarily acts as an interface between the sand and the drainage lines preventing the movement of sand into the
drainlines. The affects of sand going into the drainline would be clogging, and then loss of sand from the profile which would
then cause a settling effect on the surface creating sinkholes. The sand and gravel sizes are specified so the sand will "bridge"
on top of the gravel.
2. The gravel also acts as an equalizer with water percolation in the greens profile. Water will ALWAYS travel the path of least
resistance. "Least resistance" is what soil hydrology is all about.
Resistance is created by a few factors. Friction. Ionic Charges ( + and - ), and Pressure.
The gravel layer provides a consistent percolation of water across the green profile because of the change in hydraulic pressure
from the sand layer into the gravel layer. Pore space goes from small to large. Water is effected ionically as it passes through
the profile while gravity draws down plant unavailable water through the macropores, the large pore space in the gravel layer
creates a change in pressure leading the water to a destination as it follows its path of least resistance to the large pores. The
consistent larger pore space in the gravel layer creates a consistent pressure across the green. Helping it drain consistently.
DISADVANTAGES TO USGA SPECIFICATION GREEN CONSTRUCTION....
Nothing is perfect. There are disadvantages to using the USGA method. But like anything, the disadvantages need to be weighed against the advantages. The project needs to take into account all its specific details and assess if the risks are worth taking in the investment.
1. Cost
USGA greens can cost around the range of $15 - $18 a square foot if specified materials are used.
2. Recontouring
It is true that the option of recontouring at a later date can be costly because of the 2 layers needing to match each other. If a
USGA green is recontoured at a later date, the 12 inch sand layer across the green is altered. Creating spots that are deeper
and spots that are shallower. This inconsistency affects the consistent hydraulic properties of the design. It creates dry spots and
wet spots.
MYTHS ABOUT OTHER DISADVANTAGES TO USGA GREENS
There are alot of myths floating around the industry and in here on GCA.com that I think need to be put to sleep....
1. Settling
Settling does occur in USGA greens. But if constructed and PREPARED correctly, before a single seed is sown, ALL settling will
occur after the greens mix is installed and before any seed is put down. The greens I was taught on, and using the same
process to this day, I have never seen settling to the point that I would say that it is a problem with USGA greens.
I have been taught to calculate about a 2-3% settling percentage when calculating the amount of sand to order for a project, in
addition to ordering another 5-10% of the total order to make sure enough is ordered and there is extra for topdressing. So with
that, the green will settle around 2-3%.
The reason I have never seen settling to be a problem is because of the painstaking measures taken to properly "burp" the green
through proper preparation techniques. If a contractor jumps the gun because of a construction schedule and seeds the green
before it has completed all of its settling, more settling will occur as the green is being established and grown in. No bueno.
2. Perk Rates
To say that a USGA green will perk slower is ludicrous. Sand always drains faster than soil. Always. The uninformed would say
something like that because they dont know the whole picture.
A USGA green will perk slow or slower than a soil if it has been mismanaged. The reason for the slower perk rate is because of the
accumulation of thatch and organic material in the upper few inches in the profile. A greens perk rate will ALWAYS be as fast as its
top few inches.
If a super isnt doing his job by matching the annual rate of organic matter accumulation with a properly designed aerification and
topdressing program, the organic matter wins the race and slows down the perk rate of water starting in the upper part of the
profile.
Having a core profile physical analysis test done by a lab, which is testing the profile from top to bottom, will reveal that even when
the organic matter is slowing down perk rates up top. The sand in the middle and at the bottom of the profile are still perking
magnificently. Even 10 and 20 years later. Its the supers fault and responsibility when it comes to problems up top, not the USGA
green.
3. Disease
This one cracks me up because there is no research or studies out there to support that USGA greens create a higher disease
occurance. If there is Im sure it wasnt done in every conceivable region of the world in every conceivable climate to scientifically
support the claim. With the hundreds of different variables that occur from club to club, climate to climate. It is virtually impossible
to prove that one single variable (USGA greens) are the cause for more disease in contrast to soil greens. Soil greens get disease
just as easy as sand greens.
4. Poor Quality
Really? Isnt poor quality in the hands of the people that decide on the materials used and how they install and prepare them? How
could it be the USGA and their methods fault?
If the proper raw materials are used and they are constructed, installed, prepped, grown in and maintained properly the green will
work how it was designed to work. In any climate or region of the world.
To address what Pat has brought up, again, when he started this thread....
Yes Pat, you are right that a push-up green will always be easier to come back and recontour.
Yes Pat, USGA greens cost money
Yes Pat, USGA greens take more time than push-ups
No Pat, push-up greens will not come back. They have always been around and a viable option. IF THE SOIL DRAINS WELL.
No Pat, USGA are not hard to build. Its not hard to shape the native soil to what you want the green surface to be, and then
measure 6" for the gravel and 12" on top of that for the sand. USGA greens can be made very severe very easily.
Yes Pat, push-up greens have functioned well for their 80 year history, because of being ammended with sand for 80 years.
Yes Pat, a clubs 80 year old greens could have always been successful because when they were built, the grass being grown on
them was being cut 5x of a higher height while they were still mostly soil. Greens being cut at .500" will easily be able
to survive in a heavy soil. Just like the same grass is surviving well on our current day approaches. The approaches
of today were the greens of yesteryear. Having 500% more leaf tissue is going to improve the root system by 500%. That
is a HUGE difference in how a green is managed. HUGE.
As technology, agronomy, playing conditions and member expectations improved and increased. The original push-ups
had already been "hitting the ground running" since they were built to be groomed and conditioned for these lower
mowing heights and smoother greens. Whether or not agronomists and supers realized they were doing it. The
incorporation of sand into the profile from day one provided a soil green that would eventually drain better, mow lower,
and putt smoother. But with this came more stress on the plant and the need for ideal growing conditions.
In general, per Pats retorts to me and to everyone in general, I dont claim to know everything about anything in my life. Specifically golf, golf architecture, golf agronomy or golf course construction. All I do know is that I am a farm boy from central pennsylvania that loves the game of golf and agriculture. Ive spent the last 13 years of my life learning as much as I could about it from both the books and the field experience.
Ive encountered problems agronomically from all different angles throughout my career and have personally seen what works and what doesnt work. And specifically why or why not. This is why I feel very confident speaking, writing and debating it.
My last point I would like to make is this....
Dont look at the different techniques of green construction as "brands". Look at the raw materials used in them and how they
are used in harmony with each other.
Beyond that look at the physics of the method. The soil science, the hydrology, the chemistry. There isnt a method out there
that is perfect. There is a time and place for all 3 methods.
There also isnt a method that is trying to get someone "to buy into the science", like its trying to be a salesman and pull the
wool over your eyes. Science is science is science. It doesnt need to be sold. It sells itself. It proves itself.
Before making claims against one method or another one needs to properly troubleshoot the problem correctly and fairly, based
on proven science, research and the scientific method. To say that the clubs greens across the street has more disease and
they have USGA greens doesnt prove anything.
This is way too long and I know I havent answered some questions and comments from others. I will get to them later this evening.