Tuesday, July 19, 2011

Heat Stress + Moisture = Turf Loss?

WARNING: EXCESSIVE HEAT WARNING UNTIL 7 PM THURSDAY!

This ominous message greeted us last Friday and everyday since and doesn't look like abating anytime soon.

Its not a question of turf loss, it's a question of "how much" turf will be lost before this is over with.

The golf course is a powder keg for disease development as all three conditions for disease development are present.  First, there is a susceptible host fourteen days into a 21 day fungicide treatment schedule.  Second, free moisture and extremely humid air that prevents drying and thirdly pathogens present in the environment.

My tour of the golf course revealed up to three major diseases running unchecked on the golf course with a fourth and most destructive Pythium seen but not confirmed.  Below are pictures of diseased fairway turf.
Dollar Spot chewing its way into the canopy.
Brown Patch.  You can barely make out the smoke ring.
Not a disease, Cottonwood seed.
Turf doesn't die in straight lines.  Pythium?  Definitely Anthracnose!
Pythium starts low in the turf canopy.
This got me thinking of all the ways we lose turf during summer stress.  Here are just a few examples.
Tree's competing with turf for moisture.
Hydrophobic soils.
Malfunctioning sprinkler heads.
So what are we doing to minimize turf losses on your golf course.   First we prepared fairway turf for the stress of summer by aerifying earlier this spring and we are hoping our calendar based spray schedule will carry us through stressful times. Secondly, as we were unable to complete greens aerification due to excessive heat, greens were "vented" to allow for air exchange in the soil root zone.  Third, where we have control over moisture, sprinklers in all wet areas have been turned off or irrigation time reduced.  Greens are being hand watered to apply water to only where it is needed.  Greens are being monitored for moisture levels and disease development.  The sprayers are standing ready to roll on short notice.  Maintenance practices that cause plant stress have been curtailed until more favorable weather conditions return.

Lets pray for cooler days ahead.  _Mk