Turf Experts Question

[Sven Nilsen]

Let's use a hypothetical.


Let's say you owned a cool weather sand-based course in a rainy winter/dry summer climate that had been originally grassed with fescue.  At some point it became evident that the Poa was going to take over the greens.  In anticipation of the inevitable transition from fescue to Poa, what steps would you take to:


1.  Maintain the firm surrounds to allow for bounces onto the greens;


2.  Minimize the effects of the Poa thatch and its enhanced water retention features; and


3.  Generally prevent the oversaturation of the course during the rainiest of winters?


Assuming no such measures were taken over a 20 year period, what could you do at that point to catch up?


As an aside, should a drainage plan be based on average rainfall, or should the plan take into account what an unusually heavy rainy season might bring?


Thanks in advance,


Sven

[Tom_Doak]

Are you really asking the board to second-guess the maintenance of your "hypothetical" home courses?

[Sven Nilsen]

Are you really asking the board to second-guess the maintenance of your "hypothetical" home courses?

Tom:


Please don't take this in the cynical manner that you've assumed I meant it.


I'm really looking to learn.  I'm not a grass expert and have never claimed to be.  These are honest questions.


Perhaps someone around here would be willing to share their thoughts.  If anything, there's probably a lesson or two to be gleaned from examining the hypothetical.


Sven

[archie_struthers]

 


Sven . poa annua is one of our curses and blessing here in the mid-atlantic region of the US. When managed well and healthy it might putt better than anything anywhere.


It requires a superintendent to know it well. At Oakmont it wears like iron as the indigenous stand is ridiculously healthy despite plenty of golf and lots of heat and humidity. Maybe the cooler nights in Pittsburgh help but it's a great mystery to me.


As a rule you need to starve the poa in the spring , be careful not to over do the fertilizing and be ready to do some hand watering in the summer. Poa can be a great putting surface but it's going to require some talent from the super to keep it healthy. As to drainage keep working at improving it year after year and tearing up the thatch is always a great idea no matter what the grass. The best supers can do more with less water and that's great for playing conditions

[Kevin_Reilly]

It will be interesting to see what happens there over the coming years.  The green conditions (or at least how they appeared on social media) were pretty rough the last month or so.  Hope they recover well for high season.

[Tom_Doak]

It requires a superintendent to know it well. At Oakmont it wears like iron as the indigenous stand is ridiculously healthy despite plenty of golf and lots of heat and humidity. Maybe the cooler nights in Pittsburgh help but it's a great mystery to me.

As a rule you need to starve the poa in the spring , be careful not to over do the fertilizing and be ready to do some hand watering in the summer.

Archie:


Those are good basic principles (for almost any species of turf), but Oakmont is a different animal.


Poa annua, as the name implies, is an annual plant - it tends to die every summer, which is why it throws up so many seed heads.  If you manage it well over decades, you wind up with a sward full of the hardiest plants that survived drought and disease.  But to get there, you have to stress out the weaker plants and kill them off, which was a lot more acceptable to club members 100+ years ago than it is today!


The poa annua that infiltrates modern greens is mostly the kind that will die quickly under stress, and that’s why most superintendents overwater it.

[Kyle Harris]

Rain generally also comes with a lack of sunlight. Cloud cover for an extended is just as bad as shade.


Let’s say your hypothetical golf course is in the Pacific Northwest. How much golf traffic and inhibited photosynthesis do you believe the turf will tolerate in an unusual winter?


Let’s also suggest your hypothetical golf course has a hundred different micro-climates which most people also find ideal for golf.


Poa has several competitive advantages over other turf varieties because, as Tom noted, it is an annual plant. Poa annua seeds are viable in the soil for years and when all of the above conspire to compromise a healthy stand of anything else the Poa is already there to germinate, live out its annual life cycle, throw out more seed, and die.


That being said the answer is almost always topdress, and then topdress, followed by some topdressing.


Not for nothing, but where the climate is appropriate I believe that Poa annua are the finest putting surfaces in the world.

[Ira Fishman]

Kyle,


Very interesting. What climate is good for poa on the greens?


Thanks.

[Tom Bacsanyi]

Kyle,


Very interesting. What climate is good for poa on the greens?


Thanks.

The answer is both "all" and "none". Will defer to Kyle though.

[Wayne_Kozun]

Kyle,


Very interesting. What climate is good for poa on the greens?

Not a climate where you have an ice buildup on greens for a month or more at a time.  That is devastating to the poa on the greens.

[Alan FitzGerald CGCS MG]

There are a lot of layers to this onion and would take a lot more than I have time to write....


First of all poa annua. Yes poa annua is an annual plant, however... At greens height it takes on a different characteristic and becomes a perennial plant. If it didn't we would be seeding every poa course each spring. Funnily enough if a perennial type poa annua is let grow out, it transitions back to its annual properties. Poa adapts quickly to its environment so its characteristics change based on that too, with maintenance inputs being one of those things. Poa will grow anywhere but generally if it is taking over fine fescue greens, it generally means that the environment is more conducive for poa than fescue.


Due to the variability of poa thatch may or may not be an issue but managing it should not be too much of an issue depending on the resources available. The biggest issues with it are in extremes though. It doesn't like extreme heat or cold (or being under ice as mentioned). Thats the reason bentgrass is preferred as its easier/better more consistently all year to its ability to handle stresses better - although poa can be a much better putting surface when its happy!


Drainage is a tricky one. Personally I would go for the most extreme one as it should take care of the "normal" stuff too. The only thing to consider there tho is the methods of drainage being used as sometimes the water needs a head to push it through into the drainage medium and with lighter consistent rainfall it may not build up enough head as the volume is so light.


Aeration is always your friend but again that is not a simple answer as to what type is required/best as it all depends on your ultimate goals and the envirnoment it is needed in.