Managing water is the most difficult job our golf maintenance staff has when it comes to our golf greens. Last week, we experienced a total of 4.25" of rain over a 5 day period plus temperatures that went into the 90's for highs and above 75 for the lows which is quite unusual for June in Missouri. As we began the week, our greens were very wet and we were attempting to dry them down, basically not doing anything to them in regards to irrigation. On Tuesday, we were spot watering with a hose any potential areas that might pop up in regards to greens that were beginning to dry or drain. Some edges of greens and collars were spot or hand watered at that time. By Wednesday morning, #9 green was showing some wilt and we hand watered those areas. After watering, we took core samples to our turfgrass pathologist in Columbia, Missouri in case there were some type of disease that could have potentially created this issue. No disease was found. Heat stress created this issue. Looking at the sample under a microscope, we were able to see significant tissue that was alive in the crown of the sample. The crown is the growth area of the plant. As cooler weather arrives in the next day, we should get significant recovery of this green. Overall, the bentgrass on this green is doing well. I believe by the 4th of July weekend, there will be no visible signs of this issue.
View from the left side of the green. You can see the spots of poa that were affected.
The two pictures below give you an idea of the size of these spots in comparison to the camera case. The small holes you see in the turf are from our needle tine operation which we performed on 9 greens on Wednesday and Thursday.