Summer Stress Update.

Although the pressure of the drought and heat have been eased by a two inch rainfall on Wednesday night into Thursday morning and lower temperatures today, this summer's weather has definitely begun to take its toll on the golf course, and  I would expect that we will be back to watering very quickly, as the recent rain only put a small dent in 2012's moisture deficit.

On the course, not all of the problems of 2012 are visible on the surface, but some are.  Twelve and thirteen fairways have had some problems with dry spots, and combining the dry areas with 100 degree heat have resulted in some small areas that have died out.  Many of these spots were a grass called rough bluegrass that is very susceptible to heat stress.  Rough bluegrass is tough to kill completely though, and most of the time when the weather cools off, it will come back.  On the greens, the heat is really stressing the Poa Annua and it took on a very pronounced yellow color in many areas this week.  Without cool nights to cool off the soil and the plant, there has been no chance of recovery from the stress of the day which just compounds the stress.  Today's weather is going to go a long way towards taking some of that pressure off the turf.

Below the surface, our roots that were down deep until recently, have been creeping up closer to the surface.  With shallower roots on the greens, you will most likely see softer greens from here on out.  Without the deeper roots to get the water down in the soil, we will need to keep the soil near the surface wetter in order to provide the shallow roots with the water they need to keep the plants alive and healthy.

Now, along with the stress from the heat we are seeing some Anthracnose disease developing on 13 and 17 greens, with 13 being the most noticeable.  The disease is the bronze colored spots that are concentrated in the right center of the green.  Anthracnose typically only effects Poa Annua plants, and on 13 you can see where poa and bentgrass are mixed, the bentgrass is unaffected.  Anthracnose can be difficult to control once it has begun, so we apply preventative fungicides beginning early in the season to ensure that it doesn't develop.  Dr. Derek Settle, the turf pathologist from the CDGA, came out yesterday and confirmed my diagnosis of the disease.  He also believes that we may be dealing with a strain of the disease that is resistant to a certain group of fungicides, which would explain how it broke through our preventative treatments.  Samples of the greens were taken, so that more testing could be done to determine if this is what we are dealing with.  The greens have already been treated with a fungicide without resistance problems, so hopefully the disease is now stopped and will not spread to much more area.  When I find out the results of the testing I will post it up on the blog.

Rain!

It's been a long time since we've seen a cup full of water.  Taken Saturday, June 30.  #6 Green

Mother nature seems to have changed her mind very quickly, and because of that, our mindset is changing very quickly.  Typical for the Chicago area, if you don't like the weather, wait an hour.  Seeing as how we've been so focused on managing the drought conditions this year, you would think that we would be able to relax some with the rains that we have been seeing the past few days.  Unfortunately, this is only partially true.  While we may not have to worry about dragging hoses around, we now have to worry about disease pressures that we have not really had to face much this year.  Superintendents are rarely happy with the weather.

Rains on Friday morning brought us 1.3" of welcome rain, and a storm with heavy rain rolled through just a few minutes before I started writing this, my guess is that we have received about another half inch of rain.  Now with the forecast showing sustained heat and humidity for the at least the next week we will be shifting our scouting of the course from dry spots to pythium disease scouting.  Pythium Blight is potentially the most devastating disease that we see in this area, as it can kill large areas of turf within hours if it is not controlled quickly.  It is carried by water and is usually seen in wet, low areas and can only survive nights with high humidity and low temperatures above 70 degrees, exactly what we will be seeing for the coming week.  All of our bentgrass areas (tees, greens, and fairways) have had preventative treatments applied, but it is still possible to see breakthroughs so we will have to stay on our toes to make sure that any pythium that pops up is treated curatively and not allowed to spread.

So, although our mindset has changed for now, this summer still continues to be a challenge, and it will be a long time before we are in the clear.