Winter Injury Addendum

An ideal winter sees the greens remaining frozen through the soil profile, mostly ice-free and either covered with an ice free snow pack, or no snow at all. No thaw and refreeze takes place.  In the pictures below we like to see no ice layer at the surface and crunchy white snow: 

Older courses, like Tuscarora, have greens composed of a few different grasses.  Within that composition are species that are sensitive to ice cover and mid-winter thaw.  When we experience winter injury, damage is suffered on the Poa species in the green. Greens at Tuscarora are 30 to 70%  Poa. Newer Courses (60 years and younger) and courses that tend to be wet, have higher populations of creeping bentgrass which fares better through challenging winters. Bentgrass normally see zero injury.  Another factor that favors injury susceptibility is how intensive maintenance is. Courses that keep mowing heights low and restrict fertility through the fall to meet golfer demand for fast greens often suffer the worst when the winter is harsh. 

Poor drainage = injured turf

Greens comprised of Poa annua suffered the heaviest winter damage in drain swales and shaded areas. Predicting damage or preventing it has more to do with Mother Nature and luck unfortunately. University research on cold weather hardiness and freeze/thaw cycles is ongoing and although we know the mechanics behind the injury, avoiding it is more elusive.  If you enjoy data, the science of climate change is fascinating. Whether guided by prehistorical records, earth axis tilt/wobble, or more modern theories of  human civilization affecting warming, what's likely is over the next 100 years, northeastern winters will be warmer and wetter. This in turn, will mean Poa greens will likely suffer this damage more regularly.    

Where we go from here isn't far.  As you can see in the video, there is still life deeper down in the canopy.  From past experience we know that the majority of Poa that gets injured will regenerate from seed that's naturally always in the soil as well as from any vegetative part left intact from the winter damage.  

With regard to covers, in this instance, greens covers wouldn't have defended against either ice damage or freeze thaw cycles.  Greens covers mainly function to protect greens from wind desiccation and to speed up soil warming on courses that suffer from windy open winters.  Helpful for recovery, not so much as a freeze/thaw/ice preventative measure.

The hard part will be the waiting. We'll deploy black shade cloth to warm the worst spots when needed as well as apply fertilizers that target the recovery process.  Expect slow bumpy greens through April up to around Mothers Day.  By late May I expect to see a return to seasonally normal green speed and a full recovery by Memorial Day.  It definitely could've been worse, so we can be thankful that for whatever reason the conditions didn't damage more greens.  Whether this is a symptom of regional changes in climate, or just bad luck, try to find comfort in the fact that this isn't the first time, or the last, that Poa greens in the northeast will see winter injury.