You did a good job eliminating the other possibilities. What you must have is a fungal disease.

I'm an organic kind if guy so I use ordinary corn meal to clear up my fungal problems. I get something every spring so ever spring I find my way to the feed store to get more corn meal. If you cannot find ground corn, then cracked corn will have to do. If you try corn meal, apply it to the entire yard so you don't end up missing some of the fungus.

how about non organic?

Could it be another type of bug? Something other than grubs?

Whatever it is, it is hitting the KBG hard. It looks pretty bad.

One other data point...the other 75% of the yard still looks great. I'm just worried this stuff will continue to spread.

Outside of the professional level fungicides, which are expensive, and not easy to get, you can try Immunox, which comes in a black bottle that you attach to your hose and spray down the whole lawn paying attention to the fungal spots. Does it work? I had some brown patch appear in the beginning of the month, so I immediately treated the lawn. It seemed to stop the progression of the disease and the rest of the lawn is unaffected. From your pics it looks like it is too late for the patches of brown grass, but at the least it will probably stop any more outbreaks.

That looks like Summer Patch to me. If you have been getting rain at night or even during the day with temperatures above 80F for extended periods of time, that will cause it.

The pictures of my lawn look nearly identical to your, here they are:

{{gwi:110489}}

{{gwi:110490}}

Here is a link that might be useful: Summer Patch on KBG

Auteck,

What is the nice looking grass to the left of the sidewalk in the bottom picture? I live about 30 min south of Hickory, NC. Our temps are about the same as Raleigh, although we need to frost before Raleigh does. I was thinking about mixing in some KBG or Perninal Rye Grass into my fescue. I usually use 2nd Millenuim TTTF, but I think where i buy it from he may have some blends with KGB mixed in.

Auteck, Yes that does look just like mine.

I just applied a bottle of the Immunox. I just want to stop the spreading before my entire yard is brown. It was so nice looking one month ago. :(

Question - is the brown grass dead? dormant? some other odd state?

>" I just want to stop the spreading before my entire yard is brown"

From your pictures, the browning will stop when your practices improve!

*Look at the fertilizer stripes!!!!!
*Look how short the grass is mowed during August!!!
(I'm shocked no one has picked up on this)

Water (soak) during the summer
Raise that mower when it's hot.
Apply fertilizer *CORRECTLY* when it's cool and soak afterward.

Apply a pre emergent now, so those bare spots do not germinate poa annua. Feed heavy in fall.

Good eyes, Gary.

A lot of people simply stop mowing in the summer to get the protection of the longer grass.

When was the last time you fertilized?