New member - crop half circles

[BoRegard]

Hi everyone, new member here. My wife and I built a house on .44 acre in IL last year. The KBG sod and 12 zone 38 head irrigation system was installed in April 2018. This spring we have about 10 of these half circles popping up, a few in the front and a few in back. I’ve been doing the Scotts 4 step (last year and this year) and have applied step 1 about 2 weeks ago. The grass got too long last fall and with all the rain I never got a chance to cut it one last time before winter hence the crazy length. Any idea what is causing these circles? Fungus? I watered a ton last year since it was new sod. I searched the forum for “circles” and found some information but didn’t run across anything that looks the same as our issue. Thanks!

[Green]

Welcome. When did you first notice this? As much detail as possible, please.

[bpgreen]

Did it turn dark green before it died?

[Pway]

Could be fairy ring, though the arc is usually darker, at least in the beginning.

[BoRegard]

I first noticed last year, there were 1 or 2 half circles. I believe they popped up during fall but don’t have any pictures and am not 100% sure on timing. To be honest I didn’t think much of it. It wasn’t very noticeable because the lawn was so green. At one point I remember thinking the lawn mower tires caused it from turning in a tight circle.

2 or 3 weeks ago the circles were more green than the rest of the lawn. The brown circles were very faint but that was still early spring and everything was pretty brown. I attached a pic from April 1 2019 that my camera captured (thanks to the deer) and a pic from October 11 2018 of the same area. Thanks again.