pics?
could be fungus.

Without any more details, I'd guess "fairy ring" fungus.

How often do you water? And for how long?

Although most of Utah is desert, the most common lawn problems are caused by too much water.

It is absolutely fairy rings caused by a fungus. If the fungus is not killing the grass and you can tolerate the appearance, then leave it alone.

And if it's a fungus in Utah, the solution is simple. Stop overwatering. Don't listen to your neighbors about how often and how much to water. They're all overwatering because water is too cheap here.

Water no more than three times a week. Two times a week would be better. Once is ideal, but with our climate, it's unlikely that you'll keep your lawn green with once a week.

I'm guessing that you're currently watering daily (or twice daily). If so, that's the problem.

We have one ring in our lawn, too. It's just one perfect circle about 12 inches across. The ring is brown with a donut hole in the middle of healthy looking green grass. So weird.

I tried to figure out what the problem is but all of the circles kind of look the same. From Summer Patch to Fairy Rings... so it's hard for me to figure it out.

Maybe I overwatered this Summer too. I watered everyday anywhere from 10 to 20 minutes. It just gets so very hot in our backyard. The sun just bakes the grass.

I have the same thing in my yard.perfectly round rings of dead grass the center is still green. have no Idea

HU, Have you tried reading this topic? If you would like more information, please start a new topic and tell us where you live and what your watering schedule is.