ANNUAL REPOST: The Greens are now "Whites"

Well, it's that time of year again for the Poa annua turf, or po-anna as Johnny Miller would say, has gone to seed!  Our greens turn to "whites" and the rough becomes very wiry no matter how many times a week we cut it.  The prolific seedhead production of Poa annua is something we cannot avoid and must deal with, but remember, although it does affect playing conditions, it also benefits us as many of the millions and millions of seedheads produced end up finding their way into bare spots, divots, ballmarks, etc. to fill voids.  Our neighbours to the south have control products available to them that allow them to inhibit the seedhead production, but there are yet to be any similar products registered for use in Canada.

The timing of the seedhead production is the same each and every year so instead of spending anymore time on this blog entry, I'll share an archived one with you from May 2011.

It's that time of year...the dreaded Poa annua seedhead has arrived!

If you've played recently, I'm sure you've experienced some bumpy ball roll on the greens.  Yes, we are still recovering from aeration, but there is another contributing factor that's creating bumpiness in our greens.  The dreaded Poa annua seedhead!
 

Poa annua seedhead (white seeds) on greens

Poa annua (annual bluegrass) thrives in our wet west coast conditions and is the dominant grass species not only on our greens, but throughout the entire property!  Even at very low mowing heights of .125" (1/8"), Poa annua produces seedhead two times during a growing season, during the spring and fall.  The plant is under a great deal of stress when producing seedhead as it is exerting all of it's energy to do so.  Keeping this in mind, we must be careful not to add too much additional stress with our maintenance practices.

Not only does the seedhead affect ball roll, it also results in messy clumping after mowing in our rough - especially on wet, dewy mornings.  This prolific seedhead production typically lasts 2-3 weeks, but we have observed our species of Poa annua producing seed for 6 weeks and beyond!  Talk about stressed plants!
 

Poa annua seedhead in wet, dewy rough

There are some positives to the seedhead production of Poa annua.  The seedhead finds it's way into bare spots and germinates and matures to fill these voids.  These once bare areas are now much less susceptible to weed invasion.  When properly maintained, Poa annua can provide exceptional putting surfaces.  Some of the top courses in the world have Poa annua greens.  Oakmont Country Club is just one of them and it has hosted 8 US Opens.

Technically classified as a weed, Poa annua does have it's fair share of problems.  It tends to have shallow roots, high disease susceptibility and does not handle temperature related stresses well (heat and cold).

There are control products that suppress the seedhead production; the problem is that they are not registered for use in Canada.  Our neighbours to the south have a huge advantage in maintaining smooth putting surfaces this time of year with the use of these products!  We are keeping our fingers crossed that they will become registered and available in Canada sometime in the near future.  Until this happens, we will continue to work at improving the putting surfaces with our routine cultural practices such as verti-cutting, topdressing, rolling and fertility.  We will also be initiating our plant growth regulator (PGR) program this week.  This PGR program will help to control the different growth rates of our multiple grass species in our greens to provide smoother ball roll.

Here's to hoping this year's seedhead production is a short-lived one!