Dead Patches in Newly Established Fescue Lawn

[tcromer7]

I posted back in early April about my newly seeded fescue/kbg lawn. Things came in very nicely over the month of April and I now have an actual lawn, which I’m really excited about. Of course, I’m overly critical of the few patches that didn’t grow in for whatever reason and the weeds that germinated along with grass seed, but it’s a lot better than what I had. I knew my spring seeded stand would be very fragile over the warm months, but I didn’t expect to see dead patches in early May. It’s been a dry couple of months in NC, but I’ve been irrigating 1 inch per week… 2.5 hours one day a week, early in the morning. It hasn’t been particularly hot-a couple of days in the mid 80s-but mostly 70s for highs and 40s-50s for lows. Good grass growing weather!

About a week and a half ago, I noticed some straw-colored, circular, sunken patches in the lawn along a gentle slope adjacent to our french drain. The grass which I thought (still think) was fescue was green and healthy before that. My initial thought was fungus, but with the weather we’ve been having that didn’t seem likely. I’ve purchased some Heritage G, which I plan to start applying every 28 days starting around Memorial Day to keep Brown Patch at bay. I don’t see any characteristic fungal markings or “fuzziness” on adjacent green grass; the blades are just very dry and dead from root to tip in those areas.

It’s not grubs, I’ve dug in several patches and not found a single one. I don’t think it was POA that’s died out from sun/heat, though it does kinda look like that. There is a little POA nearby that’s still thriving for now.

My top guess at this point is that the grass must’ve just dried out too much between waterings in those spots, as it’s a south facing slope with full sun all day… but would that cause discrete circular patches? Just seems like a stretch.

What do you guys think?

[Green]

There are so many possibilities. Disease, tree roots sucking moisture, sun scald, overheated root zone from irrigation water transmitting heat to the roots, poor moisture-holding soil, etc.

Btw, remember to rotate your fungicide groups each application. Azoxystrobin repeatedly over and over is not ideal.