Patrick:

I don't think regrassing is a "solution" to anything.

Most clubs which have regrassed their greens to eliminate the Poa annua [Inverness for one] have promptly gone back and done it again ten years later.  I think having the greens out of play one year out of ten is a little taxing on the members, don't you?

Royal Melbourne regrassed all their greens to Penncross in the mid-80's to "get with the times" and they've regretted it ever since.  It took them several years to gather seed from the untouched greens on the east course and redo the greens on the Composite with the mix they'd had to start with.

 It is more than regrassing. It seems that bent needs a different micro environment than poa. It seems to need much more sun and air to prosper. So, you need to plan for that as well---tree management and airflow analysis are needed.

Jeff,

What happened at Ridgeview Ranch with the greens?  Do you know what grass they sodded with?

My recollection is that you guys originally sprigged it with Tifdwarf or Eagle, then after a couple of years+ they were redone with Champion.  Why are they having these problems?

BTW, the greens at Tangle Ridge have a bad case of bermuda infestation.  Are there ways to eradicate the bermuda without having to gas and strip the whole surface and start over?

Are we certain that Poa greens are really all that bad? Could  we possibly be over-reacting to a "condition" that might not be what has been assumed for a number of years? After all, it seems obvious that for the next thirty years or so (if not more) the USGA is committed to play our national championship on on Poa greens at least 20% of the time. This is at Pebble & Bethpage Black. By the way, the greens at the Black are fabulous year-round.

So for those, such as myself, who are "Poa-challenged," what is so po-or about Poa?

Well Pat, you've hit a nerve with me and it's not regrassing the greens it's the freakin fairways.  Here's the story at my alleged home course.  The course was built in the 50's and had some nice fairways and about 6 years ago I see the beginnings of some really ugly grass getting into some of the fairways.  I am not a GCAer at the time so I have to go to the superintendent and ask him what is going on.  He explains to me that it is some type of bermuda - more like a pure weed if you ask me - and he needs to kill it but the owners will not allocate the funds to kill it and then to resod the areas so he is not going to do anything about it.  Now the crap is all over the place and in the conditions we have this summer, it is taking over all the fairways.  It is truly ugly and when you take a divot you can wind up with about a 2 foot vine of the crap coming up.  Now, the topper in all of this is that our Greens Chairman for all these years and who did nothing about it based upon the fact that it is still there, is Brian Ault.  Now Mr. Ault has been hired to design the new course as it was announced last year that the property was going to be sold to Winchester Homes and they would build a new course along with homes.  That whole deal has met with total resistance by the environmentalists and the deal may fall through in which case we are left with garbage. I have seen this weed at some other local courses and I hope they are smart enough to deal with it before it is too late.  

Tom Doak,

A good number of courses have effectively lost their greens for this season and the likelihood is, that if another similar summer comes along, the same thing will happen.  
Perhaps it can be viewed as an investment in the future with the prospect of improved playing conditions irrespective of the weather.

When you grassed Sebonack what did you feel the effective shelf life of the grass you selected would be ?

Jerry Kluger,

I didn't limit my thread to greens.

In Chicago we have also had a tough summer, but some older greens with stuff left over from who knows when have been fine.  The greens on the South Course at Olympia Fields are some 1930 German bent/poa pos mix and have been fine, though admittedly soft because they have been watered a lot, whereas some of the North Course greens haven't been too good, especially the 2 rebuilt to USGA standards for the Open.  The North Course greens were first regrassed in 1984 or 5 to get rid of the Poa, and people say they haven't been the same since (just word of mouth though).  Word is they haven't improved since being regrassed with L-93 for the Open.  At the first meeting about a master plan for the South Course this spring, someone asked if we should regrass the South Course greens, and was met with looks of horror from one and all.

Shelly Solow can add to this, but I was at his place, Briarwood, a few weeks ago, again with pretty old stuff on the greens, and they were great.  This is admittedly anecdotal evidence (I understand Butler National's new greens are terrific), but I think generally it pays to be Hippocratic - first, do no harm.

Jeff Goldman

Kelly:

Poa sure does begin to peek it's weird little cauliflower head into the "A" strain greens in a few years. Maintenance has to get on a regular poa suppression and removal program or it will come back. They say the "A" strain is much denser than most other bents and that alone will keep poa out of "A" strain bent greens longer but that may be a bit of a wife's tale (or is it tail?).

One great point made by our USGA regional agronomist, though, is bent grass is a dry grass and poa is a wet grass.

One of the best ways then with bent greens, particularly the "A" strain, is to just get on a regular program of keeping the greens as dry as possible as often as possible. Obviously poa can't take that!  

Not to mention the fact that dry putting greens are FIRM putting greens and all that means to great playability.  

Clearly America over irrigated so much for so long that they didn't figure any of this stuff out.

1. Over-irrigated wet and soft greens are more conducive to poa and that's bullshit

2. Over-irrigated wet and soft greens are more conducive to total reliance on aerial golf and completely defeating of ground game golf and thats DOUBLE bullshit.

3. Constantly wet and soft conditions on putting greens from over-irrigation is more conducive to disease and heat stress from basically boiling in wet sub-soll conditions and that's TRIPLE bullshit and constantly closer to the "danger zone" and the death of the grass.

Do you think those three reasons, at least, are enough good reasons to begin to maintain drier putting greens with bent grass?

I sure do.

As Mayday Malone asked---do bentgrass greens, even the new "A" strains, have their own set of problems? Of course they probably do and we'll likely find out a whole lot more about what those separate sets of problems are in the future but wouldn't you think most would consider bent grass now that we're beginning to FINALLY understand what poa annua doesn't like---eg dryness??  

"One thing that may be hard for some to adapt to is when we have naturally wet conditions.  Not all turf maintenance programs have prepared for that type of condition and they get hit hard."

Kelly:

I think many of these recent threads on here on agronomy, disease, hugely dangerous weather conditions, over aggressive maintenance practices in the face of all that have gone a long way to identifying how to prepare for those types of eventualities. I think we know from the last six weeks of summer around here that naturally wet conditions followed by really high heat and humidity and right through the nights is a severe stress time for grass.

So what does one do about it to prevent loss or death. One way is to stop the aggressive maintenance practices immediately, unfortunately even if that may mean right in the midst of an important tournament. It probably means a fairly sure fix is to just open the greens and turf up and let it breath. But when grass is really on the stress edge some say even that's too disruptive and can take it over the edge.

The best solutions seem to be syringing and cooling it down but syringing doesn't solve the inherent problem of severe soil heat. Probably the last fail-safe measure is to just dump some fairly cold water on it to cool down the soil, but who is really prepared for that? A couple of courses in the last few years realize they killed their grass by dumping a lot of water on it that was too hot itself.

Or we could do what ANGC can do in the worst case---eg buy mobile snow makers and use them when the "emergency ward" turns really critical.  

The hardest thing to deal with here is that poa will always be a problem. It is one of the toughest, most adaptable plants on the planet. Just regrassing means you have taken care of your poa problem for 5-10 years. In order to have those conditions long term you must change the maintenance practices that have favored the poa over the years.

If any grass is overwatered, overfertilized and sprayed preventatively for every possible disease, you are basically raising a plant on welfare. It doesn't have to work for anything it needs to survive. Therefore when times of high stress hit it just checks out. Sometimes with little or no warning.

If you dry it out, lean it out and let a little disease work on it, then spray it before it gets to an unacceptable visual level, you are in effect thinning the herd and letting the weaker plants die off. The stronger plants survive and actually gain strength because you are making them develop and use their root system to get the water and nutrients they need to survive.

If a poa course under a bad maintenance regime wanted to change grasses I would start by tryng to overseed regularly after aerifying and with topdressing to introduce bent into the mix. Then slowly change the maintenance practices to squeeze out the weak plants and encourage the bents. Over time you would develop a tougher strain of poa mixed with bents that would fight for survival. Unless you have the money to regrass every ten years or a few extra crew members that would do nothing but manually remove poa as it shows, that is what you will end up with anyway.

I have had poa greens in the past that were very tough and putted as good as any bent except while seeding. Now we have the tools to control seedheads so that is a minimal problem.

On older greens the poa/bent ratio is in continual flux. Poa has an edge in spring and fall, while bent has the edge in the heat of the summer when the poa root system dies back.

What most don't realize is that there are hundreds of different strains of poa that adapt to different conditions. Some will adapt to dry, lean conditions and do well. I have not been to Oakmot, but if those greens stimp at 13 every day, I would say that is some tough poa that has adapted through the years to the management practices applied there and is evidently one of the best putting grasses in the world.

Pat,

Poa is a prolific seed producer at ANY height of cut. Some strains produce more than others, but a single plant can produce dozens of seeds per week. Bent produces almost none because that is what we have bred it to do. I don't know this for fact, but have heard that poa seeds can lay dormant in the soil for more than 10 years waiting for the right conditions to grow. It is very tenacious. Therefore any seed that makes it's way onto a course through tracking or bird droppings etc. has a chance to germinate. When it is not seeding, it looks just like a bentgrass plant so it isn't noticed, though in some seasons it is a lighter green. It then seeds, seeds spread, repeat... On greens you can manually remove it before it spreads too far if you have the manpower to do so. On fairways it is impossible to keep up with. When you have it in your fairways it WILL spread to the rest of the course.

The many different strains also make it unbelievably adaptible to any environment. It is the poplar tree of the grass world. It will fill in any opening in the turf. The first poa you see will grow fast, seed hard then die. Succeeding generations will adapt and learn how to survive longer in the environment they are provided while continuing to seed heavily. It will grow in soils that are so compacted that nothing else will. But the seeds also loves aerifier holes.

This is why trying to fight it off is futile. The only way to limit it is to manage your turf to give your preferred grasses every edge that you can.

All I know about Oakmont is what I've heard. "They had to slow the greens down to hold the Open." and many more like comments. Like I said, I've never been there.

I do not pretend to have the expertise of the greenkeepers who have been kind enough to participate in this discussion.  I have served as a green chairman for more than 10 years and on the turfgrass committee of our local Golf Association for some time so that there is some basis for my observations.  I think that management is more important than grass types although the newer strains do have some significant advantages.  At my home course we have greens with a variety of dominant strains all with varying degrees of poa.  Some of our original greens, circa 1921, still retain a significant stand of Washington Bent (a truly wonderful grass) on a natural push up medium.  Several others were rebuilt in the 70's and 80's with Penncross varieties on push up medium.  We also have 3 new greens built on a modified USGA medium using a mixture of the new L and A strains which are 4 years old.  During this difficult summer, our greenkeeper, Paul Voykin, kept all of them in good shape rolling at about the same speed each day.  He adjusted to the changes in heat and moisture and treated each green differently depending on its particular circumstances.  Green speeds were increased for a day or two for tournaments but greens were slowed when recovery was needed.  We also allowed some poa to burn out and then aerated and seeded with bent to try to increase the percentage of bent grass.  Careful management can allow most types of greens to survive.  On the other hand, some nearby courses with new greens made up of the newer strains lost several greens this summer because they place them under too much stress.  Paul would tell you that the newer grasses appear to be easier to maintain but that proper management is the key regardless of ht grass involved.