Where do you live?

What kind of grass do you have?

What is your watering schedule? How often and for how long?

When were the last two times you fertilized and what did you use?

Can you take a close up picture from 3 inches away in a spot where the grass seems to change from green to brown? The best pictures are taken when it is overcast or in the shade.

Here's a tip for your trees. The tree trunks are buried under mulch. Dig out the mulch until you can see the big roots flaring out away from the trunk and never bury it again. Trunk bark is different from root bark. If trunk bark stays moist it will rot and, essentially, girdle the tree. If you see little roots growing into the mulch on the way down to the big roots, cut those off.

I live near Marysville WA, about 40 miles north of Seattle.

Grass is a mix of rye and fescue.

We have in ground irrigation which runs each of 17 zones for about 15 minutes between 2 am and 6 am every day except Saturday because I mow on Saturday.

I only fertilized once this year with 16-16-16 fertilizer.

I decided to put an application of the 16-16-16 fertilizer + lime + grass seed on this area and I did additional watering of about 2 hours twice a day and now these spots have pretty much disappeared.

Yes, the builder mounded up the soil around the trees, or maybe he graded it down in the rest of the lawn. When we had the grass installed we had the contractor add some mulch/bark but we plan to remove this until we get down to the roots as you describe.

The Last pic Looks like summer patch with the "frog eye", did you put down a fungicide?

I didn't put down a fungicide. Please see my last comment which says the area seems to have recovered and these spots are pretty much gone.

Thanks,

Don