I live in southeast Michigan. I built my house 2 years ago and had sod laid down last year.
I was told to water twice a day at least. The grass has held in and it came green during this season with no issues. I have reduced the watering to a single time a day and everything was perfect.
Suddenly within 2 days yellow spots appeared in different areas of the lawn.
I used Grub control in May of this year.
I used Scott turf builder weed and feed in June.
I applied grass food in July.
What is causing these yellow spots? How do I fix them?
Update: here are some pictures from different areas.