Yellow spots growing?

[Rodrigo]

Hello,

About two weeks ago a couple of yellow spots started to appear in my otherwise very nice and green Lawn. I'm a noobie to lawn-care so I would appreciate your advice.

I don't think it is lack of water because the yellow spots have very nice green blades intermingled with the yellow seemingly dead or diluting blades.

I treated with fungicide a week ago but the yellow keeps growing.

There are also some other blades turning yellow in the middle of very green zones.

Should I be concearned and tray this somehow or is the grass just starting to go dormant? This lawn is in Austin Texas, where the days have gotten shorter but the temperatures are still mild (75 highs 45 lows).

I'm attaching some pics. Thanks for any comments.

Following is a closeup of some blades yellowing in an otherwise very green area

 

[Chuck]

Looks like brown patch disease. Lift up on the blades of grass. If they pull up easily and the base of the leaf blade is rotted then it is brown patch. It is common this time of year. It is due to too much water. Stop watering and apply horticultural cornmeal.

 

[Rodrigo]

Thank you so much for the diagnosis and treatment advice